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Epifaunal assemblage of a newly established oyster reef with two substrates

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Title:
Epifaunal assemblage of a newly established oyster reef with two substrates
Physical Description:
Book
Language:
English
Creator:
Dow, Ian M
Publisher:
University of South Florida
Place of Publication:
Tampa, Fla
Publication Date:

Subjects

Subjects / Keywords:
Crassostrea virginica
Epifaunal community development
Artificial reef establishment
Alternative substrate
Sediment burial
Dissertations, Academic -- Marine Science -- Masters -- USF   ( lcsh )
Genre:
non-fiction   ( marcgt )

Notes

Summary:
ABSTRACT: An artificial oyster reef constructed in Boca Ciega Bay, off of the War Veteran's Memorial Park, St. Petersburg, Florida, in 2005, was used to compare a mined shell material to the typical oyster shell substrate used in artificial reef projects as an alternative substrate and cultch material. Half of the reef's veneer was the fresh oyster shell and the other half was mined material. Experimental trays were deployed on top of the sediment along the leeward reef base and sampled quarterly to test the hypothesis that fresh shell is the preferential cultch material of the Eastern Oyster, Crassostrea virginica, promoting more oyster and epifaunal community development than the mined material. Monthly field observations along the reef face monitored the oyster community development on both substrates. The unanticipated influence of the reef's presence on the local current flows resulted in significant sediment loading on the reef.The sediment inundated and smothered the experimental trays over the course of the study, thereby converting the trays from hard substrate to soft bottom habitats. Any influence the different substrates might have had on community development was overwhelmed by sediment burial. Monthly field observations revealed positive oyster community development on both substrates. Live oyster abundance was significantly dissimilar between June and December 2006 on the fresh shell compared to the mined material (R = 0.241, p = 0.001). Epifaunal abundance showed even greater dissimilarity over the same time period (R = 0.474, p < or = 0.001). Greater abundances of large oysters were found on the fresh shell substrate due to an instability and deterioration of the larger pieces of mined material. A low replicate sample size of n = 3 leaves results from between month and between quarter sampling analyses open to interpretation.Though no definitive conclusions were drawn, the data from the community analyses provides useful information on the species inhabiting and utilizing oyster reefs in the Tampa Bay area.
Thesis:
Thesis (M.S.)--University of South Florida, 2008.
Bibliography:
Includes bibliographical references.
System Details:
Mode of access: World Wide Web.
System Details:
System requirements: World Wide Web browser and PDF reader.
Statement of Responsibility:
by Ian M. Dow.
General Note:
Title from PDF of title page.
General Note:
Document formatted into pages; contains 75 pages.

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University of South Florida
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Resource Identifier:
aleph - 002001444
oclc - 319838982
usfldc doi - E14-SFE0002655
usfldc handle - e14.2655
System ID:
SFS0026972:00001


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ABSTRACT: An artificial oyster reef constructed in Boca Ciega Bay, off of the War Veteran's Memorial Park, St. Petersburg, Florida, in 2005, was used to compare a mined shell material to the typical oyster shell substrate used in artificial reef projects as an alternative substrate and cultch material. Half of the reef's veneer was the fresh oyster shell and the other half was mined material. Experimental trays were deployed on top of the sediment along the leeward reef base and sampled quarterly to test the hypothesis that fresh shell is the preferential cultch material of the Eastern Oyster, Crassostrea virginica, promoting more oyster and epifaunal community development than the mined material. Monthly field observations along the reef face monitored the oyster community development on both substrates. The unanticipated influence of the reef's presence on the local current flows resulted in significant sediment loading on the reef.The sediment inundated and smothered the experimental trays over the course of the study, thereby converting the trays from hard substrate to soft bottom habitats. Any influence the different substrates might have had on community development was overwhelmed by sediment burial. Monthly field observations revealed positive oyster community development on both substrates. Live oyster abundance was significantly dissimilar between June and December 2006 on the fresh shell compared to the mined material (R = 0.241, p = 0.001). Epifaunal abundance showed even greater dissimilarity over the same time period (R = 0.474, p < [or] = 0.001). Greater abundances of large oysters were found on the fresh shell substrate due to an instability and deterioration of the larger pieces of mined material. A low replicate sample size of n = 3 leaves results from between month and between quarter sampling analyses open to interpretation.Though no definitive conclusions were drawn, the data from the community analyses provides useful information on the species inhabiting and utilizing oyster reefs in the Tampa Bay area.
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Alternative substrate
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PAGE 1

Epifaunal A ssemblage of a N ewly E stablished O yster R eef with Two S ubstrates by Ian M. Dow A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science College of Marine Science University of South Florida Major Professor: Norman J. Blake, Ph.D. Pamela Hallock Muller, Ph.D. Aswani K. Volety, Ph.D Date of Approval: October 29th 2008 Keywords: Crassostrea virginica Epifaunal Community Development Artificial Reef Es tablishment, Alternative Substrate Sediment Burial Copyright 2008, Ian M Dow

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A CKNOWLEDGEMENTS I would like to express my gratitude and appreciation to my major advisor, Dr. Norman Blake, for his guidance experience, knowledge, and fish tal es. The c hance to work on this study has provided me with a new direction and opened new doors for me. I would also like to thank my other committee members, Dr. Pamela Hallock Muller and Dr. Aswani Volety, for their assistance and expertise throughout t he project and the formation of my thesis Funding for this work was provided by the National Oceanic and Atmospheric Administration (NOAA), the Pinellas County Environmental Fund (PCEF) and the University of South Florida. Special t hanks to Noland E l sae sse r for proposing this project, for showing me the rope s, and for helping me along the way T hanks to Bridgit McCrickard f or always being in the thick of it with me Both of t heir a dvice, knowledge, friendship and willingness to a lw ays lend a h and were essential to the completion of this project. I would also like to acknowledge several individuals for their assistance over the duration of this project. Thanks to Elon Malkin and Greg Ellis for their repeated assistance during samp le collections. Thanks to Mark Berrigan (Florida Department of Agricultural and Consumer Services) for supplying the needed shell material Thanks to Duncan Seawall for constructing the reef on which the entire project was based. Finally, thanks to all o f my friends and family who have supporte d me througho ut this project and my en tire academic career. I could no t have come this far without your support.

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i TABLE OF CONTENTS LIST OF TABLES ................................ ................................ ................................ ............. iii LIST OF FIGURES ................................ ................................ ................................ ........... iv ABSTRACT ................................ ................................ ................................ ...................... vii INTRODUCTION ................................ ................................ ................................ .............. 1 Hypothesis ................................ ................................ ................................ ...................... 6 METHODOLOGY ................................ ................................ ................................ ............. 7 Experimental Reef ................................ ................................ ................................ .......... 7 Interstitial Space Estimates ................................ ................................ ............................. 9 Treatment Set Up and Deployment ................................ ................................ ................ 9 Treatment Sampling ................................ ................................ ................................ ...... 11 Monthly Field Observations ................................ ................................ ......................... 12 Data Collection: Quarterly Experimental Trays ................................ ........................... 14 Water Quality Surveys ................................ ................................ ................................ .. 14 Experimental Treatment Analysis and Statistics ................................ .......................... 15 RESULTS ................................ ................................ ................................ ......................... 19 Substrate Interst itial Volume ................................ ................................ ........................ 19 Monthly Field Observations ................................ ................................ ......................... 19 24 Hour Water Quality Survey ................................ ................................ ..................... 23 Monthly Water Quality ................................ ................................ ................................ 25 Quarterly Experimental Trays ................................ ................................ ...................... 25 March June September 2006 Analysis ................................ ................................ 26 December 2006 Analysis ................................ ................................ .......................... 30 DISCUSSION ................................ ................................ ................................ ................... 34 Monthly Field Observation Analysis ................................ ................................ ............ 41 Experimental Tray Analysis ................................ ................................ ......................... 44

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ii CONCLUSION ................................ ................................ ................................ ................. 49 REFERENCES ................................ ................................ ................................ ................. 51 BIBLIOGRAPHY ................................ ................................ ................................ ............. 56 APPENDICES ................................ ................................ ................................ .................. 58 Appendix A: Post Construction Water Quality Surveys ................................ .............. 59 Appendix B: Species Abundance Tables ................................ ................................ ..... 60

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iii LIST OF TABLES Table 1: 1 way ANOSIM results for monthly field observations Global R values report ranked average level of similarity between substrates; 0 = total similarity, 1 = total difference. Bold values are significant at p < 0.1. ................................ .................... 20 Table 2: List of all tax a observed in during the monthly field observations. ................................ ................................ .......................... 23 Table 3: Global ANOSIM R values for response variables measured in the first three collections, March September 2006. R values in bol d indicate statistical significance at p< 0.05. ..................... 29 Table 4: Global ANOSIM R values for response variables by collection period. R values in bold indicate statistical significance at p< 0.05. ................................ ................................ .......... 29 Appendix A 1: Post construction, 24 hour water quality survey, windward face: measurements were taken every two hours at the same location on both sides of the reef; (E) indicates Ebb Tide, (F) indicates Flood Tide. Sa linity values calculated from conductivity measurements ................................ ................................ ..... 59 Appendix A 2: Post construction, 24 hour water quality survey, leeward face: measurements were taken every two hours at the same location on both sides of the reef; (E) indicates Ebb Tide, (F) ind icates Flood Tide. Salinity valu es calculated from conductivity measurements ................................ ................................ .... 59 Appendix B 1: Species abundances observed in each treatment replicate sample collected in March 2006. ................................ ............................ 6 0 Appendix B 2 : Species abundances observed in each treatment repli cate sample collected in June 2006. ................................ ............................... 6 4 Appendix B 3 : Species abundances observed in each treatment replicate sample collected in September 2006. ................................ ...................... 68 Appendix B 4 : Species abundances observed in each treatment replicate sample collected in December 2006. ................................ ...................... 7 2

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iv LIST OF FIGURES Figure 1: Map of St. Petersburg, FL and location the artificial reef off the Google Earth, 2008. ................................ ................................ ....................... 7 Figure 2: Diagrammatic cross section of the reef depicting construction material distribution ................................ ................................ ....................... 8 Figure 3: Aerial view of the War Veteran's Memorial Park Reef during construction in Autumn 2005 ................................ ................................ ....... 10 Figure 4: Distribution o f experimental trays along the leeward base of the reef (December 2005). The dimensions of the experimental trays are not drawn to scale. ................................ ................................ ......... 12 Figure 5: Diagrammatic representation of sampling deployments. 0.25m 2 quadrats were deployed below MLW along the reef face; experimental trays were deployed on top of the sediment along the base of the reef. ................................ ................................ ...................... 13 Figure 6: Algal growth and accu mulation during February 2006 along the leeward reef face ................................ ................................ .......................... 13 Figure 7: Average live oyster spat per substrate type, January December, 2006. Observations were from 0.25m 2 quadra ts placed randomly on top of each substrate type on the leeward reef face, n = 3. Error bars are standard deviations. ................................ ............................... 20 Figure 8: Average live spat observed monthly on fresh shell substrate f rom 0.25m 2 quadrat field observations, by size classes; error bars are in standard deviation. ................................ ................................ ................... 21 Figure 9: Average live spat observed monthly on mined material substrate from 0.25m 2 quadrat fie ld observations, by size classes; error bars are in standard deviation. ................................ ................................ ..... 21 Figure 11: Pooled observations of epifaunal species richness for the two experimental substrates, n = 3 per substrate. ................................ ............... 24

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v Figure 12: Temperature and salinity measurements taken monthly between January and December 2006. ................................ ................................ ....... 25 Figure 13: Average live o yster spat of experimental treatments per collection period, March December 2006. Note that the December collection is not directly comparable. ................................ ......... 26 Figure 14: Average species richness (S) of experimental treatments per collection period, March December 2006. Note that the December collection is not directly comparable. ................................ ......... 27 Figure 15: Average spat abundance and percent mortality o f C. virginica per average percent mortality per treatment. Percentages reported for the remaining collections report the percent of dead oysters observed per treatment Note that 100% ind icates that all articulated oysters observed in the replicates were dead while observed ................................ ................................ ................................ ....... 28 Figure 16: Cluster analysis dendrogram of live oyster abundance averages between experimental treatments per collection period, March December 2006. ................................ ................................ ........................... 31 Figure 17: MDS plot of species richness (S) of experimental treatment replica tes categorized by collection periods. Distance between points indicates relative degree of similarity between the samples. ................................ ................................ ................................ ........ 32 Figure 18: Cluster analysis dendrogram of the epifaunal assemblag e abundances for all 48 experimental trays categorized by collection period. Dendrogram based on results of Bray Curtis similarity. ................................ ................................ ................................ ..... 33 Figure 19: Influence of salinity when oyster reef metrics are used as performance target variables for restoration projects. Dotted lines indicate range of surface salinities recorded at the War December 2006. Tolley and Volety (personal communication). ................................ ............................... 35 Figure 20: Example of sediment loading observed on experimental trays, September 2006 A: Computer enhanced picture of an experimental tray in situ. B: Picture of experimental tray taken at the surface after re trieval. ................................ ................................ ......... 40

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vi Figure 21: Example of algal accumulation on leeward face of the reef, February 2006. ................................ ................................ ............................. 41 Figure 22: Examples of mined ma terial substrate samples after spontaneous fracturing during lab analysis. ................................ ................................ ...... 45

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vii Epifaunal A ssemblage of a N ewly E stablished O yster R eef with T wo S ubstrates Ian M. Dow ABSTRACT An artificial oyster reef constructed in Memorial Park, St. Petersburg, Florida in 2005, was used to compare a mined shell material to the typical oyster shell substrate used in artificial reef projects as an alternative substrate and cultch material. Ha shell and the other half was mined material. E xperimental trays were deployed on top of the sediment along the leeward reef base and sampled quarterly to test the hypothes i s that fresh shell is the preferential cultch material of the Eastern Oyster, Crassostrea virginica promoting more oyster and epifaunal community development than the mined material. Monthly field observations along the reef face monitored the oyster community development on both substrates. the local current flows resulted in significant sediment loading on the reef. The sediment inundated and smothered the experimental trays over the course of the study, thereby converting the trays fr om hard substrate to soft bottom habitats. Any influence the different substrates might have had on community development was overwhelmed by sediment burial. Monthly field observations revealed positive oyster community development on both substrates. L ive oyster abundance was significantly dissimilar

PAGE 10

viii between June and December 2006 on the fresh shell compared to the mined material (R = 0.241, p = 0.001). Epifaunal abundance showed even greater dissimilarity over the same time period (R = 0.474, p < 0.001 ). Greater abundances of large oysters were found on the fresh shell substrate due to an instability and deterioration of the larger pieces of mined material. A low replicate sample size of n = 3 leave s results from between month and between quarter samp ling analyses open to interpretation. Though no definitive conclusions were drawn, the data from the community analyses provides useful information on the species inhabiting and utilizing oyster reefs in the Tampa Bay area

PAGE 11

1 INTRODUCTION As a result suffered significant habitat losses. Over the last 100 years, 44% loss of emergent vegetation and 81% loss of seagrass (submergent vegetation) has been recorded in Tampa Bay (Hoffman et al. 1985) In addition to these salt marsh and seagrass bed habitats, the reef habitat provi ded by the eastern oyster ( Crassostrea virginica ) has also experienced significant declines due to anthropogenic influences. While the eastern oyster has been recognized for its economic value, its ecological value in the estuarine system of Tampa Bay has been largely underestimated. The eastern oyster is capable of surviving in both subtidal and intertidal environments. The eastern oyster can also live in temperatures ranging from 0 36 0 C, and salinities ranging from 0 40 psu (Shumway 1996, Lenihan 1999) allowing it to inhabit estuarine and coastal waters from the Gulf of St. Lawrence to Argentina (Carriker & Gaffney 1996, Lenihan 1999) A ble survive in wide temperature and salinity variat ions, oyster have the highest growth and reproductive rates, and lowest overall mortality, in temperatures ranging from 20 30C and salinities ranging from 15 to 30 psu (Shumway 1996, Leniha n 1999) In areas such as the Mid and South Atlantic, and Gulf coasts, populations o f oyster are commonly restricted to intertidal zones (Roegner & Mann 1995) Given s expansive geographic range and high temperature and

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2 salinity tolerances, the eastern oyster provides key habitat which performs important ecological functions and services in many estuarine systems. The improvement of water quality by oyster filtration is one of the more common services associated with a successful oyster reef, and is often used as a measure of successful reef habilitation/restoration. Improved water qua lity indirectly suggests an increase in oyster filtration capacity, and consequently implies a growing and prosperous oyster reef. Newell (1988) calculated that before 1870, the oysters of Chesapeake Bay could filter the entire volume of the bay in 3.3 days while the reduced oyster populations of the Chesapeake in 1988 required 335 days (Coen et al. 1999b) At temperatures above 25 0 C Lang efoss and Maurer (1975) found that an adult eastern oyster can filter up to eight liters of water per hour for each gram of dry wei ght tissue. The improvement in water quality, commonly associated with a decrease in phytoplankton concentrations in relation to oyster biomass, can lead to a decrease in the effects of eutrophication. Oyster filtration can also be used as a means of ass essing water quality. Because oysters bio accumulat e toxins oyster tissue can be analyzed to determ ine the concentration of toxins in the water column over time (Peachy 2003) Other charact eristics of the eastern oyster also cause it to play a significant ecological role in many estuarine systems. In many estuaries along the Mid Atlantic and Gulf coasts, oyster reefs provide the primary source of har d substrate, through which they may suppo rt a variety of organisms (Peterson et al. 2003, Luckenbach et al. 2005) The formation of oyster reefs over time can provide stable structure and vertical relief for many different fish and macroinvertebrates, besides oysters, in soft bottom or unstructured habitats. The physical structure provided by

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3 oysters is important in regulating local faunal populations as well as community dynamics (Jones et al. 1994, Lenih an & Peterson 1998) V ertical relief can provide oysters a means of avoiding an oxygen depleted bottom and burial in areas with high sedimentation rates (Breitburg et al. 2000) The extent to which reef structures are found in areas of suitable oxygen concentrations also greatly affect the spatial distribution, behavior, a nd survival of oyster reef fishes and decapods (Breitburg 1999) Habitat complexity associated with reef produced vertic al relief is known to enhance fish and decapod utilization (Breitburg 1999, Breitburg et al. 2000) C urrent flow rates are also influenced by the vertical structure of oyster reefs The influence of flow disturbance on oyster reefs is reflected primarily throug h its effect on sedimentation processes. Oyster recruitment, growth and survival rates are sensitive to increased sedimentation (Kilgen & Dugas 1989, Ortega & Sutherland 1992, Lenihan 1999, Saoud & Rouse 2000, Thomsen & McGlathery 2006) Flow is altered not only by reef presence, but also ree f height; local flow speed has been found to increase with both reef height and elevation (Lenihan 1999) Thus, s lower flow along reef bases results in settlement of suspended solids. Organisms, especially new recruits and juveniles of species such as oysters and other sedentary epifauna near the sediment water interface are generally the most strongly affected (Wilson Jr. 1981, Brenchley 1982, Posey 1986, Emerson 1989, Bonsdorff et al. 1995) as cited in Hinchey et al. (2006) While Kilgen and Dugas (1989) noted that oyster reefs are typically found in areas free from sediment deposition or siltation, studies have found the sediment tolerance of C. virginica is largely dependent on duration and degree of burial. An experiment by Hinchey et al. (2006) using different level of sediment stress reported 100% oyster survival after 6 day

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4 burial with 5mm of sediment. While able to tolerate sh ort term burial, oyster mortality increases with longer periods of sediment deposition (Lenihan 1999) R eef formation also promotes further oyster larvae settlement by providing a clea n, stable substrate for settlement. The interstitial spaces and increased structural complexity created by oyster shells provides oyster spat protection from predation, climate extremes, and space competition (Bartol & Mann 1999, Coen et al. 1999a, Bartol and Mann (1999) found that substrates providing sufficient interstitial spaces, such as oyster shell, allow settlement of oyster larvae down to a depth of 10cm below the reef surface. They also observed that during the warm summer months, temperatures just 10 cm below the intertidal reef surf ace were 11 0 C cooler. They suggested that the oysters below the surface benefited from shading by the overlying oysters, resulting in a moister, cooler, and more hospitable environment than that of the reef surface. In part, the structural complexity pr ovided by these interstitial spaces makes oyster reefs attractive habitats for many macroinvertebrates and fish. A study by Lehnert and Allen (2002) suggested that even the little structural complexity provided by loose shell rubble on oyster shell bottoms can act as primary habitat for several commercially important fish and crustaceans. skilletfish, striped ble nny, feather blenny, and the oyster toadfish, are highly depende nt on oyster reefs, utilizing the habitat for feeding, shelter and reproduction. The interstitial spaces in oyster reefs make ideal nests to protect their eggs and larvae (Breitburg 1999) A nother critical element to consider in the development of a successful artificial reef is the substrate of the reef. Whil e oyster shell has been the substrate of choice, the

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5 growing cost of an d limit in the supply of oyster shell has stimulated research into alternative substrates. Studies have looked at numerous materials as suitable alternative substrates for creating oys ter habitat including c lamshell ( Rangia cuneata ), limestone, gravel, concrete, concrete stabilized gypsum (Haywood et al. 1999) ; dredged ma terial (Clark et al. 1999, Priest III et al. 1999, Powell & Ashton Alcox 2004) ; oyster shell, clamshell, and ash pellets and plastic sheets (Devakie & Ali 2002) (2000) found that clamshell and ash pellets were only suitable alternatives when there was high oyster recruitment and if the substrate was mounded to provide sufficient vertical rel ief. Substrates already containing oyster shell, either recently dead or previously seeded spat, have been found to enhance settlement of oyster spat through chemical emissions (Tamburri et al. 1992, Turner et al. 1994) While Haywood et al. (1999) found al. (2000) suggests that only substrates that provide adequate interstitial space can support the development of a viable reef. Coupled with determining which substrates are preferentially settled by oyster spat, factors such as substrate stability and subsidence need to be considered. For example, use of a less dense substrate with a larger surface area would be ideal in a soft bottom estuary to avoid reef subsidence. Conversely, at a site with high wave action, a heavier, more stable substrate might be necessary to avoid the reef being broken down and washed away. Creating a successful and viable oyster reef requires the consideration of all of the factors mentioned above and more. The proper s ubstrate must be chosen to survive physical conditions of the estuary, while providing an attractive and structurally complex

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6 surface to stimulate settlement of naturally occurring oyster larvae. Additionally, for the reef to be successful it must be able to provide the ecological services, i.e. complex vertical structure, predation protection, and juvenile protection, needed to attract not only oysters, but also the many invertebrates and fish that are associated with naturally occurring oyster reefs. Th e purpose my study was to compare recruitment on two experimental substrates fresh oyster shell and mined shell material Specifically, I examined the natural recruitment, growth and survival of Crasso s trea virgin i ca spat and the development of the assoc iated epifaunal assemblage to determine the influence of the different substrates on reef development. In addition, I compared substrates with preset oyster spat with un pretreated substrates to determine the effect presetting live o ysters has on natural oyster recruitment and the development of the associated epifaunal assembla g e. Hypothesis I hypothesize that the fresh oyster shell will be the favored reef substrate, stimulating increased levels of larval settlement. I also hypothesize the densest spat settlement will occur on the fresh oyster shell with preset spat. Finally I hypothesize that the greatest epifaunal community development will be associated with the fresh shell with spat treatment, due to the increased oyster density

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7 METHODOLOGY E xperimental Reef Construction of the 600x20ft reef by Duncan Seawall began in mid May 2005. The oyster reef ( Figure 1 ) was constructed approximately 20 0 m southwest of the western The reef was constructed using recently dead oyster shell and mined shell material as the reef surface substrates. The fresh oyster shell was collected from several restaurants in Figure 1 : Map of St. Petersburg, FL and location the artificial reef off the shore of War Vet

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8 the area and from the Florida Department of Agricultur e and Consumer Services (DOACS). All of the fresh shell was stored and aged on Weedon Island. The mined material was shell aggregate in a mudd y shell matrix which was taken from a local active shell mine. Before construction, both the mined material and fresh oyster shell were transferred to the boat ramp at WVMP. Once transferred, the shell was taken from the boat ramp, loaded onto a barge an d transported to the reef site. The mined shell material was used to provide the base along the entire length of the reef. A geotextile, biodegradable cloth was then placed over the base and then covered with the substrate veneers ( Figure 2 ), mined material over the northern half, and fresh shell over the southern half. Limestone boulders (approximately 2 foot diameter) were then placed along the windward ree f face, the top of the reef, and used to cap the northern and southern ends of the reef. The shell substrate was left exposed on the leeward (eastern) face of the reef. The reef was constructed at mean low tide level, leaving the 1 2ft of the reef surfac e exposed during low tide ( Figure 2 ). Figure 2 : Diagrammatic cross section of the reef depicting construction material distribution

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9 Interstitial Space Estimates (2000) the interstitial space volume of both substrates was measured by volumetric displac ement. The substrate contents of each tray were placed in 5 liters of water. The change in water volume reflected the interstitial space of each substrate. Five replicate measurements were taken for each substrate to generate a mean value and standard d eviation. These values were then compared using a one way ANOVA. Treatment Set Up and Deployment Once the reef construction ( Figure 3 ) was complete, an expe rimental design similar to that of Coen et al. (1999a) Bartol and Mann (1999) and Whitlach and Osman (1999) was implemented. T o non destructively sample the reef, 48 screen lined plastic trays (43.8 cm x 30.0cm x 9.0cm) capable of holding 2 in ches of shell were deployed on the reef. The plastic screen mesh (1mm 2 ) was attached to the bottom and sides of the trays using Star Brittle Marine Silicon Sealant. The first 24 trays were filled with fresh oyster shell and the remaining 24 trays were fi lled with the mined material. The 48 trays consisted of twelve replicates for each of the four experimental treatments: fresh oyster shell, mined material, fresh oyster shell with preset oyster spat, and mined material with preset oyster spat. The 24 unseeded trays tested the hypothesis that fresh oyster shell is a more favorable substrate for spat settlement than the mined material. Comparatively, the remaining 24 seeded trays tested the hypothesis that the presence of live oyste rs enhances the natural recruitment on the reef, regardless of the substrate type.

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10 To seed the preset experimental trays, the substrate contents from 12 fresh shell and 12 mined material trays were individually placed in pla stic mesh bags and suspended in the water in scallop cages off the docks of the USF College of Marine Science. The bags were submerged from April to mid September 2005. Prior to deployment on the reef, the experimental substrates with preset spat w as transferred back into the experimental trays and mean baseline measurements were calculated for each substrate. All valves were inspected for oyster spat as well as for any other organisms that needed to be removed. To quantify the density of oyster s pat seeded on the 12 baskets of fresh shell and 12 baskets of mined shell, an average was taken. The oyster spat in six of the twelve baskets of each treatment were quantified by dividing the oyster sizes into size classes. The size classes used were: 1) 0 4.9mm, 2) 5 19.9mm, 3) 20 29.9mm, 4) 30 39.9mm, and 5) 40 49.9mm, etc. All measurements of shell height were made to the nearest 1.0mm using dial calipers and a field ruler. The associated flora and fauna that Figure 3 : Aerial view of the War Veteran's Memorial Park Reef during construction in Autumn 2005

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11 settled on and among the shell during th e settlement period were identified, counted, and removed using a toothbrush and a knife as needed. Experimental trays were deployed on December 14 th 2005 after the preset oyster spat had been quantified and all associated flora and fauna had been remove d. The length of the reef was divided into three locations : North, Middle and South. At each location four replicate trays of each treatment were placed approximately 2 3 feet apart on top of the sediment along the leeward base of the reef ( Figure 4 ). This experimental tray configuration was used to account for the potential variation in the treatment replicates T o facilitate t reatment identification and location of during retrieval, each treatment was identified by different colored cable ties attached to the outside of the trays. Treatment Sampling The 90 day (1 st quarter) collection was conducted on March 14 th 2006. Usi ng random selection, a single replicate of each treatment was collected from the north, middle and south reef locations Trays were pulled directly from the sediment, placed on a floating raft, and ferried back to shore. On shore, the contents of each tray were emptied onto a 3ftx3ft (1 mm x 1mm mesh) swath. Then the mesh wrapped tray contents were gently rinsed in the seawater to remove the accumulated sediment. The sampling tray was also rinsed in the seawater, filling the tray with just enough water to sieve the sediment off the walls and base, but taking care to not to submerge the tray. Then the tray contents and tray itself were examined for any mobile macrofauna. Macrofaunal contents of each tray were placed in labeled glass jars containin g 10% formalin for later

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12 identification and enumeration in the lab. The washed experimental trays were then transported back to USF College of Marine Science and placed in a freezer to preserve any live oyster spat and other attached species present for l ater identification and counts. The above procedures were repeated for the 180, 270, 365 day collections. Figure 4 : Distribution of experimental trays along the leeward base of the reef (December 2005). The dimensions of the experimental trays are not drawn to scale. Monthly Field Observat ions Monthly field surveys of the exposed leeward reef face began in January 2006 Three randomly placed 0.25m 2 quadrats at both the north and south reef ends were used to survey the fresh sh ell and mined material veneers. Quadrats were placed approxima tely 1 1.5ft below mean low tide ( Figure 5 ). Densities and size distributions were recorded for both live and dead oyster spat observed in each quadrat. The size classes used were: 1) 0 4.9mm, 2) 5 19.9mm, 3 ) 20 29.9mm, 4) 30 39.9mm, 5) 40 49.9mm, 6) 50 59.9mm, 7) 60 69.9mm, 8) 70 79.9mm and 9) 80 89.9mm. A ll

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13 measurements of shell height were made to the nearest 1.0mm using a field ruler. Due to the high le vel of mortality in the preset experimental trays and the extended time between the collections, a dead oyster was defined as an oyster where the right valve was still attached. The presence of the right valve was taken to imply that the oyster in questio n died during the study period, and not prior to or during the presetting of the oyster spat. Figure 5 : Diagrammatic represent ation of sampling deployments. 0.25m 2 quadrats were deployed below MLW along the reef face ; e xperiment al trays were deployed on top of the sediment along the base of the reef. Taxonomic identifications then species richness and abundances were also recorded. Any fish or mobile fauna observe d at or between quadrats along the reef were also noted. When water clarity permitted, digital images were taken of each quadrat. Because there was a marked increase in algal and sediment coverage on the reef substrates between January and Figure 6 : Algal growth and accumulation during February 2006 along the leeward reef face

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14 March 2006, placement of the monthly quadrats was restricted to areas of low algal accumulation ( Figure 6 ) Water quality and sedimentation data was also collected as part of the monthly reef observations. Water temperature and salinity were measured using a n YSI 30/50 FT unit. Data Collection: Quarter ly Experimental Trays Once an experimental tray was removed from cold storage and thawed, residual sediment was carefully removed from each piece of substrate and then examined for any organisms Each piece of substrate was then carefully scrutinized from all angles. Densities and size distributions were recorded for the both live and dead oyster spat observed in each experimental tray. The size classes used were: 1) 0 4.9mm, 2) 5 19.9mm, 3) 20 29.9mm, 4) 30 39.9mm. Oyster shell lengths were measur ed to the nearest 1.0mm with a field ruler. All epifauna and sessile fauna were identified to the lowest taxa possible and species richness and abundances recorded. Once all the pieces of substrate had been examined the remaining rubble in the tray bott oms were carefully sifted through for any organisms missed. Water Quality Surveys A post construction, 24 hour water quality survey was conducted on April 5, 2006 using a hand held Horiban probe for measuring turbidity, temperature, conductivity/salinity total dissolved solids, and dissolved oxygen. Measurements were taken at mid depth every 2 hours at the mid point inside the reef and at the mid point outside the reef.

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15 Experimental Treatment Analysis and Statistics The effects of the experimental trea tment, collection period, and reef locations on the oyster and epifaunal densities were compared by grouping the data into different categories, or response variables. Seven response variables were chosen to quantify the viability of the experimental subs trate treatments as suitable oyster cultch and reef building materials. The se seven response variables were: 1) l ive o yster d ensity (oyster abundance per sample) 2) t otal o rganism a bundance 3) e pifau nal a ssemblage a bundance 4) s pecies r ichness 5) b ivalve s pecies a bun dance 6) d ecapod s pecies a bundance and 7) m obile t axa a bundance Values for each of the above response variables were determined for every sample tray and then used in both univariate and multivariate statistical analyses. The live oyster density variable wa substrates, fresh oyster valves and mined material, as viable oyster cultch material and any effect the substrates might have on the overall growth of the oysters. The size class distributions of the live oyst er spat were additionally used when applicable to compare the effect of the preset oyster spat had on natural spat settlement and growth. The oyster reef, the ba se reef substrate must support the colonization of not only oysters, but also the associated macrofaunal assemblage. The remaining six response variables were

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16 used to assess the substrates ability to support the establishment of a viable oyster reef inver tebrate community. Due to the nature of the quarterly samplings, experimental trays collected from one quarterly collection cannot be considered as replicates of another. Consequently, the majority of the statistical analysis conducted involved 16 experi mental treatments divided by their collection periods, instead of the four original experimental treatments. In addition, since the 12 remaining experimental trays were removed from their original place of deployment to avoid sediment burial, the data fro m the December collection were analyzed separately from th e data from the previous collections ANOVA (Analysis of Variance) statistics were used to test the a priori groupings (experimental treatments, collection periods, and reef locations) of the experi mental trays. All abundance data were square root transformed prior to analysis to downweight the influence of the most common species (Clarke & Gorley 2006, Tolley et al. 2006) Homogeneity of the variances was tested usin g the Levene statistic. For cases where the assumptions of ANOVA were not met, alternative non parametric univariate and multivariate statistical analyses were carried out using the PRIMER 6 (Plymouth Routines In Multivariate Ecological Research) statisti cal package. Statistical tests used for this study were cluster analysis, Analysis of Similarity ( ANOSIM ) and m ultidimensional scaling (MDS). Cluster analysis, ANOSIM, and MDS are all permutation/randomization tests that make a minimum number of assumpti ons about the relationships between the samples and are based on the information summarized in the ranks of resemblance matrices. The ANOSIM test can be applied to any resemblance matrix (Clarke & Gorley 2006) but are only appl ied to Bray Curtis similarity matrices

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17 for the purposes of this study. Due to the large amount of zeros in the abundance data sets, a dummy value of one was substituted for zero values to calculate all resemblance/similarity matrices. Cluster analysis and MDS ordination were utilized to search for any natural groupings (Tolley et al. 2006) within or between the experimental treatment samples, collection periods or reef locations for any of the response variables measured in this study. Using the dendrograms output by the cluster analysis, the degree to which clusters of samples are similar or dissimilar can be determined. Similarly MDS plots provide a representation of the sample data in low dimensional (2 d) space. Poi nts that are close together represent samples of similar composition and points further apart correspond to samples that are more different in composition. MDS plots where the associated stress values were > 0.2 were not considered useful for interpretati on (Clarke & Gorley 2006) Both univariate and multivariate analys e s were done using the non parametric approximate analogue to ANOVA, the ANOSIM test. ANOSIM allows for the test of the null hypotheses that there is no assemblage difference between a priori grouping of samples specified by the levels of a single factor (treatments, collections periods, or reef location). ANOSIM is not a valid test of the differences between groups generated after inspection of the data, such as cluster analysis or MDS scaling. The ANOSIM test statistic, R, is centered around zero; if there are no d ifferences in the test variable(s), then the average rank resemblance among and within groups will be much the same, and R will be near zero. The R statistic is scaled so that R varies roughly between 1 and 1; R ilarity) between groups though ecological communities rarely have R < 0; R=1: all dissimilarities between the categories of a

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18 chosen factor (treatments, collections periods, or reef location) are larger than any dissimilarity among samples within that fac tor. ANOSIM results are primarily reported as a global R statistic, along with a p value which is determined by the number of permutations that result in an R value greater than or equal to the global R statistic. When the global R statistic is much larger than any of the default 999 permutated values calculated, it results in a significance level of p <0.001 (Clarke & Gorley 2006) R values > 0.5 were considered to show dissimilarity between the samples and R values < 0.5 to show similarity between samples. In the case of the current study, the signi ficance of the ANOSIM analysis is limited by the sample size. Due to sampling design limitations, sample size for either the monthly quadrat observations or the quarterly experimental trays is limited to n=3. As a result, in the pairwise ANOSIM results, the lowest p value is p =0.1. Therefore, for the purposes of this study, ANOSIM statistics reporting p values of 0.1 were considered significant

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19 RESULTS Substrate Interstitial Volume umetric displacement of the substrates yielded a mean change in volume of 780cm 3 83.7 for the fresh shell and 1020cm 3 44.7 for the mined shell material. The mined material had a significantly larger interstitial volume than the fresh shell substrate (F = 32, F = 5.318, p = 0.00048). Monthly Field Observations Though observations on the reef began in January 2006, live oyster spat was not observed within the quadrats until the following April. Subsequent field observations found that ther e were consistently more live oyster spat on average growing on the fresh shell than on the mined material ( Figure 7 ). 1 way ANOSIM results comparing these m onthly averages for oyster spat abundance showed significant dissimilarity (p < 0.1) between the substrates for each month except October ( Table 1 ) Global similarity of spat abundance observed on the substrates between June and December 2006 was weaker than the monthly comparisons (R = 0.241, p = 0.001).

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20 Figure 7 : Average l ive o yster s pat per s ubstrate t ype, January December, 2006. Obs ervati ons were from 0.25m 2 quadrats placed randomly on top of each substrate type on the leeward reef face, n = 3. Error bars are standard deviations Table 1 : 1 way ANOSIM results for monthly field observations. Global R values report ranked average level of similarity between substrates; 0 = total similarity, 1 = total difference. Bold values are significant at p < 0.1. Substrates Similarities for: June July August Sept. Oct. Nov. Dec. 6 Month Total Oyster Abundance 0.704 0.7 04 N/A 1 0.185 0.815 1 0.241 Epifaunal Abundance 0.704 0.407 N/A 0.667 0.222 0.333 0.63 0.474 Steady monthly growth was observed on the fresh shell substrate through the appearance of oysters in continually larger size classes ( Figure 8 ) between June and December of 2006. The greatest average number of live spat observed on the fresh shell per size class was in the July: 5 19.9mm size class, with an average spat abundance of 67 oyster spat/0.25m 2 ( Figure 8 ). 0 20 40 60 80 100 120 140 Jan Feb Mar Apr May Jun Jul Sep Oct Nov Dec Average # of Oyster Spat/0.25m2 quadrat Month Average Live Oyster Spat Densities per Substrate Type, January December 2006 Fresh SD Mined SD

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21 Figure 8 : Average l ive s pat o bserved m onthly on f resh s hell s ubstrate from 0.25 m 2 quadrat field observations by size classes ; e rror bars are in standard deviation. Similar growth patterns were observed for the mined material substrate; however the patterns appear reduced in both the average spat abundance and in the number of size classes observed per month. The largest live spat obser ved on the mined material was > 60mm in length ( Figure 9 ). Side by side comparison of substrates size class Figure 9 : Average l ive s pat o bserved mo nthly on m ined m aterial s ubstrate from 0.25m 2 quadrat field observ ations by size classes ; e rror bars are in standard deviation. 0 20 40 60 80 100 120 June July Sept Oct Nov Dec Average # of Individual Oyster Spat Month Monthly Average Live Spat Size Class Abundances for Fresh Shell Substrate, June December 2006 > 0 4.9mm > 5 19.9mm > 20 29.9mm > 30 39.9mm > 40 49.9mm > 50 59.9mm > 60 69.9mm > 70 79.9mm > 80 89.9mm 0 10 20 30 40 June July Sept Oct Nov Dec Average # of Individual Oyster Spat Month Monthly Average Live Spat Size Class Abundances for Mined Material, June December 2006 > 0 4.9mm > 5 19.9mm > 20 29.9mm > 30 39.9mm > 40 49.9mm > 50 59.9mm > 60 69.9mm

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22 distributions show greater spat ab undance and growth between June and December of 2006 for the fresh shell substrate. By December 2006, oysters greater than 80 mm in length were observed on the fresh shell, while oysters less than 60mm in length were observed on the mined material. The fresh shell substrate shows greater spat growth and density than the mined material ( Figure 10 ). Figure 10 : Comparison of oyster spat size class distributions on t he fresh shell versus the mined material substrate, June December, 2006. Twenty two taxa were observed and identified on the experimental substrates between January and December 2006 during the monthly quadrat observations ( Table 2 ). No quadrat data were collected during August 2006 due to poor weather conditions and poor water clarity. Global R values for epifaunal abu ndance between June and December 0 4.9 5 19.9 20 29.9 30 39.9 40 49.9 50 59.9 60 69.9 70 79.9 80 89.9 0 10 20 30 40 50 60 70 June July September October November December June July September October November December Oyster Spat Size Classes (in mm) Average # of Live Oysters Experimental Substrates 0 4.9 5 19.9 20 29.9 30 39.9 40 49.9 50 59.9 60 69.9 70 79.9 80 89.9 Mined Material Fresh Shell

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23 2006 showed some dissimilarity between the two substrates (R = 0.474, p < 0.001). Monthly comparisons of the average epifaunal abundances yielded significant dissimilarity between the substrates in June, September, October and December. While significant at p < 0.1, similarity values in October for both the oyster spat and epifaunal abundances were the lowest observed ( Table 1 ). Drasti c increases in pooled species richness in June 2006 on both substrates ( Figure 11 ) contradicted the June ANOSIM results for the average epifaunal abund ance ( Table 1 ). Conversely, the pooled species richness for both substrates in November and December ( Figure 11 ) reflect the significant dissimilarities detected between the average epifaunal abundances ( Table 1 ) of the subs trates for December Table 2 : List of all taxa observed in during the monthly field observations. Taxonomic Diversity Monthly Quadrats N = 22 Serpulid sp Styela plicata Balanus eburneus Botryllus sp. Balanus amphitrite A nadara sp Anomia simplex Brachidontes exustus Sabellid sp. Eurypanopeus depressus Crepidula fornicata Synaptula hydriformis Crepidula maculosa Ophionereis reticulata Callinectus sapidus Terebellidae Worm Unidentified Diodora sp. Gobiosoma r obustum Bugula neritina Stylochus ellipticus Styela canopus Cliona sp. 24 Hour Water Quality Survey The considerable variability in measurements taken for the 24hr water quality survey (Appendix A, Tables A 1 and A 2) was mainly due to the highly variable wind and currents. A 15mph northwesterly wind stirred the surface waters during the afternoon and early evening hours but decreased to less than 10mph in the early morning.

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24 This was particularly evident in the turbidity measurements which ranged from 8 90 NTU with a mean of 28.7 NTU on the eastern or leeward side of the reef and 8 180 NTU with a mean of 59.4 NTU on the western or windward side of the reef, an indication that the reef may contribute to a reduction in turbulence over the adjacent s eagrass bed. The wave action and turbulence also resulted in supersaturated dissolved oxygen (DO) readings of greater than 8.0 mg/l throughout the survey on both sides of the reef. Figure 11 : Pooled observations of epifaunal sp ecies richness for the two experimental substrates n = 3 per substrate. O n the other hand s alinity and temperature showed little variation between the beginning and end of the 24 hour period with the changes only reflecting tidal stages. D espite a 0.7 m tidal fluctuation during the survey, repeated m easurements revealed only slight difference s in salinity and temperature on either side of the reef (Appendix A). 0 2 4 6 8 10 12 14 16 Jan Feb Mar Apr May Jun Jul Sept Oct Nov Dec Pooled # of Observed Species Month Pooled Epifaunal Species Richness by Month, January December 2006 Fresh Shell Mined Material

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25 Monthly Water Quality Temperature and salinity show seasonal variation from January to Dece mber 2006. Temperature fluctuations reflect expected seasonal variation with an August high of 32 o C and December low of 20 o C ( Figure 12 ) Salin ity values ranged from 28 34ppt during the course of this experiment. The reef experienced increased levels of precipitation in April and June, resulting in the salinity values below 30. Figure 12 : Temperature and salinity mea surements taken monthly between January and December 2006. Quarterly Experimental Trays The goal of the original experimental design for the quarterly tray collections was to display the continued oyster reef community assemblage development over the cou rse of the 2006 year for both experimental substrates. Comparisons of data from a given collection were to elucidate the effect the different substrates was having on community 0 5 10 15 20 25 30 35 0 5 10 15 20 25 30 35 40 Temperature (0C) Salinity (ppt) Months Monthly Salinity and Temperature: January December 2006 Salinity Temperature

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26 composition. Unanticipated sedimentary influences however necessitated the mo vement of final 12 trays, the December 2006 set, to avoid complete tray burial. As a result, the December sample set was not included in the between collection comparisons. March June September 2006 Analysis Trays collected during the first quarter s howed no colonization by oysters and little by other epifaunal organisms ( Figure 13 and Figure 14 ). Trays with preset oyster spat experienced severe levels of mortality. Average preset spat baselines were calculated for the preset treatments prior to the experimental tray deployment The baseline data showed that the trays had average oyster densities of 266 4 and 340 4 for the fresh shell and mined material respectively Figure 13 : Average live oyster spat of experimental treatment s per collection period, March December 2006 Note that the December collection is not directly comparable. Replicates of these preset treatments collected in March showed near complete preset oyster mortality, with live oyster spat averages of 89 and 102 for the fresh shell with spat and mined material with spat treatments respectively ( Figure 15 C and D). 0 100 200 300 400 500 600 March June Sept. Dec. Average Number of Live Spat Observed Collection Period Fresh Shell Mined Material Fresh Shell with Spat Mined Material with Spat

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27 Figure 14 : Avera ge species richness (S) of experimental treatments per collection period, March December 2006 Note that the December collection is not directly comparable. The lowest oyster spat densities were observed during the June collection, however the first li ve oyster spat on the non spatted substrates were also observed in the June collection. Newly settled oysters were observed on all experimental treatments by the September collection. The greatest oyster densities in the September collection were obse rved on both of the mined material treatments ( Figure 13 ) The Levene statistic indicated that the variances in the first three collections were heter ogeneous and therefore violated the assumptions of ANOVA. Consequently non parametric analyses were used. The results of the ANOSIM between the three collection periods are summarized in Table 3 No significant dissimilarity in spat density was observed between the experimental treatments or between the experimental treatments partitioned by collection period. Holistically, or by treatment, the reef location fact or was not shown to have any significant influence ( Table 3 and Table 4 ). 0 5 10 15 20 25 30 35 40 45 March June Sept. Dec. Average Species Richness, n = 3 Collection Period Fresh Shell Mined Material Fresh Shell with Spat Mined Material with Spat

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28 Figure 15 : Average spat abundance and percent mortality of C. virginica per treatment by collection period. Percentages report average percent mortality per treatment Percentages reported for the remaining collections report the percent of dead oysters observed per treatment Note that 100% indicates that all articulated oysters observed in the replicates were dead while or alive, were observed The temporal factor appears to have the more dominant influence on the differences detected in the response variables ( Table 3 Figure 16 and Figure 18 ). For differences detected between treatments or reef locations within a single collection period, on ly March and December show any significant R Values ( Table 4 ). 100% 42% 17% 30% 0 200 400 600 800 1000 1200 1400 1600 March '06 June '06 September '06 December '06 Average Number of Articulated Oysters Observed Collection Periods Fresh Shell Treatment Average Dead Average Alive A A A ** 50% 21% 21% 0 200 400 600 800 1000 1200 1400 1600 March '06 June '06 September '06 December '06 Average Number of Articulated Oysters Observed Collection Periods Mined Material Treatment Average Dead Average Alive B 94% 98% 81% 28% 0 200 400 600 800 1000 1200 1400 1600 March '06 June '06 September '06 December '06 Average Number of Articulated Oysters Observed Collection Periods Fresh Shell with Spat Treatment Average Dead Average Alive C 93% 99% 56% 43% 0 200 400 600 800 1000 1200 1400 1600 March '06 June '06 September '06 December '06 Average Number of Articulated Oysters Observed Collection Periods Mined Material with Spat Treatment Average Dead Average Alive D

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29 Table 3 : Global ANOSIM R values for response variables measured in the first t hree collecti ons, March September 2006. R values in bold indicate statistical significance at p< 0.05. The only significant dissimilarities detected in live spat density (R= 0.66, p < 0.05) were in the March collection. Subs equent pair wise comparisons of the treatment replicate averages calculated for the March collection indicated the dissimilarity in spat density was between the non spatted and spatted treatments (Fresh Shell, Fresh Shell with Spat: R = 1, p =0.1; Fresh Sh ell Mined Material with Spat: R = 1, p = 0.1; Mined Material, Fresh Shell with Spat: R = 1, p = 0.1; Mined Material, Mined Material with Spat: R = 1, p = 0.1). There was no difference detected between the two non spatted treatments (Fresh Shell M ined Material: R = 0, p > 1) nor between the two spatted treatments (Fresh Shell with Spat, Mined Material with Spat: R = 0.074, p > 0.1). Table 4 : Global ANOSIM R values for response variables by collection period R values in b old indicate statistical significance at p< 0.05

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30 With the exception of the mined material with spat treatment in June, the average species richness for each of the experimental treatments significantly increased (R = 0.444, p < 0.05) between March and September 2006. Figure 14 shows the increasing trend of the average species richness (S) values for the treatments across the first th r e e collection periods. Clustering of e xperimental treatment replicates in Figure 17 reflects how the species richness between the experimenta l treatments became increasingly similar over the course of the year long study. While the March September species dissimilarity (R = 0.541, p < 0.05) was detected in the epifaunal assemblage abundance variable. Similar to the oyster abundance variable, the differences detected between the samples for the epifaunal response variables were significant due to the collection period factor rather than the experimental treatme nt or reef location factors ( Table 3 ). Within the June and September collections no differences were detected for any of the experimental response variables for ei ther the treatment or reef location factors ( Table 4 ). December 2006 Analysis Each treatment saw a noticeable increase in the average spat density for the December collection contrasted with the previous collections ( Figure 15 A, B, C and D). Though the fresh shell treatment appears to have a greater density of l ive spat than the other treatments ( Figure 13 ), no significant similarity/dissimilarity was found between

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31 Figure 16 : Cluster analysis dendrogram of live oyster abundance averages between experimental treatments per collection period, March December 2006. the December spat densities ( Table 4 : R = 0.191, p > 0.05). March was the only month that showed any significant dissimilarity (R = 0.66, p< 0.05) between the oyster densities on the experimental treatments ( Table 4 ). The greatest average live spat density observed in December was on the fresh shell with an average of 488 339.8 spat/tray. Comparatively, both fresh shell treatments had greater average spat densities that either of the mined mat erial treatments ( Figure 13 ). The experimental treatments all experienced increased epifaunal utilization by December 2006. The epifaunal assemblage abundance for each of the treatments was significantly different in pairwise comparisons between the September and December 2006 collections: Fresh Shell Sept, Fresh Shell Dec: R = 0.815, p =0.1; Fresh Shell with Spat Sept Dec: R = 0.926, p = 0.1;

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32 Mined Ma terial Sept Dec: R = 0.741, p = 0.1; Mined Material with Spat Sept Dec: 0.593, p = 0.10. Though the epifaunal assemblage abundance and the total organism Figure 17 : MDS plot of species richnes s (S) of experimental treatmen t replicates categorized by collection periods. Distance between points indicate s relative degree of similarity between the samples. abundance showed statistical significance ( Table 4 ), neither reported any significant dissimilarity between the experimental treatment replicates collected in December ( Table 4 and Figure 18 ). The remaining response variables measured for the December collection showed neither statistical significance nor significant dissimilarity between the experimental treatments ( Table 4 ). The arbitrarily chosen reef locations factor showed no influence on any of the measured variables. ANOSIM tests involving the reef locations between the first three collections or within the December collection showed neither statistical significance nor significant dissimilarities for any of the oyster or epifaunal abundance variables ( Table

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33 3 ). ANOSIM tests involving the reef locations within any single collection period also showed neither statistical significance nor significant dissimilarities for any of the Figure 18 : Cluster analysis dendrogram of the epifaunal assemblage abundances for all 48 experimental trays categorized by collection period. Dendrogram based on results of Bray Curtis similarity. oyster or epif aunal abundance variables ( Table 4 ). This lack of any statistical significance strongly suggests the locations along the reef had no influence on the variables meas ured for each of the experimental trays.

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34 DISCUSSION Of all factors and variable that have limited this study, it is particularly important to note the influence the replicates had on the overall results collected. Consequent of the restraints and limitations faced, replicate sizes of three were used in both sampling methods. Due to time and manpower constraints, only three replicate quadrat observations per substrate were made during the monthly field samplings. While the experimental tray deploy ment configuration effective ly accounted for possible variation due to the length of the reef each collection was limited to replicate size of three. As a result of this design and the unexpected complications previously mentioned, both the oyster and co mmunity data sets were rather variable. PRIMER was used for the non the variability inherent in the data. Unfortunately, non parametric analyses are also negativel y affected by low replicate numbers. Due to the low replicate levels, only a p value of 0.1 could be obtain ed within a single collection analysis and therefore had to be considered the minimum attainable Though the statistics calculated adequately expl ained observation made in the study, any conclusions drawn are open to interpretation. T o assess the success of a restoration project, the goals of the project must be clearly defined. Once the goals are clearly outlined, appropriate variables must be

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35 se lected to measure the success of the project (Luckenbach et al. 2005) Most restoration effort s involve a large number of variables, so it is necessary to measure variables that will reflect the progress toward meeting the aims of the project. The measurements chosen should also be appropriate for the conditions surrounding the project. As Figure 19 illustrates, the surface salinities surrounding a potential restoration site should be considered in choosing what type of variables are selected as performance targets to indicate successful oyster reef restorations. Figur e 19 : Influence of salinity when oyster reef metrics are used as performance target variables for restoration projects. Dotted lines indicate range of surface salinities Dec ember 2006. Tolley and Volety (personal communication). ject, there were two main goals. The first was to determine if mined material would be a suitable substra te for the establishment of a new artificial oyster reef and its associated community when

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36 compared to a typical oyster cultch substrate. The second was to determine if the presence of live preset oyster spat would enhance natural oyster settlement and th e development of the associated macrofaunal assemblage. Given the project goals and the salinities recorded at the reef ( Figure 12 ) the biodiversity and species abundance variables chosen as indicators of success were appropriate. Though the different volumes and periodicities used in the two sampling methods prevent direct comparisons of their respective data sets, indirect inferences are necessary to make sense of the results obtained. The two data sets of oyster settlement and growth on the two substrates presented conflicting results. The field observations showed strong oyster population growth on both substrates, with oysters reaching heights of 60mm and more (see Figure 8 and Figure 9 ), and continuous l arval settlement and growth with little mortality. In contrast the experimental trays showed 9 months high spat mortality ( Figure 15 A D). Although b oth data sets were collected from the same leeward face of reflect the combined influence of several unexpected and limiting stresses. The vertical gradient or height of reefs in the water column, well know n to influence species distributions on rocky intertidal reefs (Thomsen et al. 2007) has also been found to influence current velocities along oyster reefs (Lenihan 1999, Thomsen & McGlathery 2006) Current flow speeds were found to va ry more with reef height rather than water depth. In relation to reef height, current flow was found to be higher at the crest of reefs than along the bases. Lenihan (1999) used this variation in local flow with reef height to explain the different sedimentation rates he observed. As flow speeds decreased with the gradient of the reefs, the increased sedimentation rates on the reef

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37 increased oyster mort ality; in cases of low profile reefs, complete reef burial was observed (Lenihan 1999) These variations in the flow environment additionally help to explain variations that are often observed in factors such as spat recruitment and mortality (Ortega & Sutherland 1992, Lenihan 1999) the feeding of sessile organism, algal growth and accumulation (Lenihan 1999) and the creation of hypoxic /anoxic bottom conditions. In the present study, the influence of flow variance across the reef gradient is evident in the results obtained. The two sampling strategies record ed the recruitment a t the upper face and along the base of the artificial reef ( Figure 5 ) By December 2006, live oyster shell lengths were found to be in excess of 60mm ( Figure 8 and Figure 9 ) along the reef face, but none greater than 40mm were found alive along the base. The difference in shell growth between the two heights was similar across the experimental substrates, strongly implying that the growth patterns observed were the result of variances in the local hydrodynamics, similar to those foun d by Lenihan (1999). While the macrofaunal community data equally were influenced by the variance s produced by the local hydrodynamics at the two reef heights, comparison of the data sets is problematic because the sampling methods and targeted assemblag es were so different community data were limited to species found living on the exposed portions of the substrat e that could be identified visually in the field ( Table 2 ). Analysis of the contents in the experimental trays involved a thorough examination of each piece of substrate, yielding a more thorough and comprehensive record of the species that colonized the substrates (Appendix B). The more expansive community set of the trays does not imply

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38 greater community development at the base of the reef; the difference is simply a result of the sampling methods The sediment accumul ations and algal overgrowth observed in this study were the most influential manifestations of the current variances experienced by the reef substrates. Particularly during the first three months of the study, both of these factors significantly influence d the remainder of the experiment. At the onset of the experiment, each of the experimental trays was placed on top of the sediment. Each tray was filled with either clean substrate, or substrate preset with live oyster spat. However, by the first quart erly collection, each of the trays had accumulated a 5 10mm layer of fine sediments on the substrate surfaces, with similar sediment build up around the outer perimeters of the trays (personal observations). Clean, hard surfaces are required for successfu l spat recruitment (Kilgen & Dugas 1989) Multiple studies have found that sediment stress on substrate surfaces lessens oyster density by reducing viable substrate space for recruitme nt (Ortega & Sutherland 1992, Lenihan 19 99, Saoud & Rouse 2000, Thomsen & McGlathery 2006) Sediment stress similarly affects juvenile and adult oyster growth because the ciliate gills of C. virgin i ca are sensitive to clogging with sediment (Ortega & Sutherl and 1992) Oysters normally combat sediment stress by closing their valves and changing to temporary anaerobic metabolism. By switching to anaerobic metabolism, adult and juvenile oysters are able to survive short durations of partial or even complete b urial (Hinchey et al. 2006) While altering the metabolic pathways usually provide oysters an effective temporary solution to sediment stress, the oysters in the exp erimental treatments of this study experienced prolonged stress due to continual sediment accumulation which severely reduced settlement and survival (see Figure 15 A D) along

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39 the reef base. Stronger sedimentation along the base was likely the product of weaker water flow at the reef base compared to the flow along the upper portion of the reef. The degree to which the experimental tray substrates were layered with fine sediments ( Figure 20 personal observations) supports the assertion that sediment inundation strongly influenced the remainder of th e study. The unexpected sedimentation at the reef base rendered the preset oyster spat portion of the experiment null. The rapid sediment burial resulted in severe oyster mortality in the preset oyster spat treatments in the first quarterly collection in March 2006. By the second quarterly collection (June 2006), the average mortality levels of the preset oyster trays had increased to 98% of spat observed ( Figure 15 A and C). Despite the presumed mortality of the preset spat in the preset treatment trays that remained deployed in the field, the non spatted and spatted treatments were considered as separate treatments throughout the analysis because it w as impossible to determine what effect, if any, the preset oysters had on either natural oyster recruitment or on the start of the associated community in the trays during the first three months. Stress due to algal overgrowth has been found to have simila r effects as sediment stress on oysters. Manifested primarily through the fouling of potential substrate for settlement, strong algal accumulation (>2kg WW m 2 ) (Thomsen & McGlathery 2006) has been found to strongly inhibit oyster recruitment (Ortega & Sutherland 1992, Thomsen & McGlathery 2006) Just after the experimental deployment in December 2005, the reef experience d an explosion of drift algae accumula tion during the winter months. Both along the reef face ( Figure 21 ), at the base, and along the adjacent seagrass bed, large masses of opportunistic algae, such as Ulva lactuca and Enteromorp ha spp.,

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40 had built up. Though not uncommonly seen drifting in Tampa Bay during the winter months, the algae never left the reef as spring came and the water warmed. In March Figure 20 : Example of sediment loading observed on e xperimental trays, September 2006 A: Computer enhanced picture of an experimental tray in situ. B: Picture of experimental tray taken at the surface after retrieval 2006, three months after the initial appearance of the algae, ma cr oalgae still blanketed the majority of the reef face and the adjacent seagrass bed all the way to shore (personal observations ). The algae began to die off and accumulate at the reef base and surrounding areas once the water temperature began to rise ( Figure 12 ) Organic mat erial from the intense algal decomposition settled directly into the sediments surrounding the reef. Prevalent odor of hydrogen sulfide (H 2 S) from the sediments at the reef base and within the experimental trays suggest the combined influences of continua l sediment burial and increased organic input promoted hypoxic to anoxic conditions at the reef base. Oyster abundance data from the second collection (June 2006) support this reasoning. Live oyster abundance for the preset treatments dropped noticeably between March and June 2006 ( Figure 13 ); 98% of the oyster recorded in the June preset trays were dead ( Figure 15 C and D, second column), and at least 42% of the newly settled oysters observed in the non spatted trays were dead ( Figure 15 A and B, second column).

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41 With <1 0 C rise in temperature between May and June 2006, the data suggests that the reduction in algal cover allowed increased invertebrate colonization. Assuming that the algae along the upper reef face was washed away as it decomposed, the influence of the Figure 21 : Example of algal accumulation on leeward face of the reef, February 2006. algal coverage in the month Both oyster recruitment levels ( Figure 7 ) and epifaunal species richness ( Figure 11 ) significantly increased between May and June 2006 on both substrates. Monthly Field Observation Analysis As suggested above, the sediment and algal accumulatio ns significantly influenced the early portion of the study. However, by June 2006, most of the algae had died off and the effect of the continual sediment loading was minimized by the daily tidal cycle currents and wave energy from increased boat activity in the adjacent intercoastal waterway. The tidal currents and wave action worked to continually re suspend the majority of the sediment that settled on the upper reef face. The result was continually turbid surface waters and a thin persistent layer of sediment on the substrates. While this sediment layer did not deter substrate colonization, it did obscure the observation of

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42 newly settled spat and biased the field observations. The significant increase in the abundance of spat 5mm and greater ( Figure 8 and Figure 9 ) observed in the quadrats in June 2006 sugges ts that spat was present on the substrates earlier in the study, just not recorded because the small spat was obscured by turbid water and sediment cover. Field observations found robust growth of the oysters on both substrates despite the presence of the sediment on the reef starting in the summer months and continuing through the remainder of the study. While the frequencies of the smaller size classes decreased as the study progressed, oysters in larger size classes began to appear. Though repeated ob servations were not made of the same area of substrate, the trend suggests continual growth of the oysters throughout the study for both substrates with continual supply of new oyster spat recruitment throughout the 2006 year ( Figure 10 ). Evidence of epifaunal community establishment in the field observations began to appear just as oyster spat began to appear on the substrates in the first quarter of 2006. Significant increases in species richness occurred ( Figure 11 ) on both substrates as the water temperature warmed and algal coverage on the sub strate decreased. Further oyster and invertebrate growth and colonization continued through the year for both substrates, peaking in July 2006. Interestingly, by July 2006, there was significantly more oyster growth and invertebrate utilization on the f resh shell substrate than the mined material. The initial conclusion was that the data reflected the hypothesized oyster preference of the fresh shell over the mined material as cultch material. The fresh shell substrate consistently showed significantly higher values each month in all measures recorded. While this seemed like a reasonable conclusion, it was noted that during the monthly mined material

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43 quadrats with increasing frequency t hroughout the study. Bare patch is defined as an area where extensive disaggregation of the mined material had occurred. It should be noted that the mined material substrate used was a shell aggregate in muddy matrix. Further examinations of these patche the reef but rather had broken down, leaving a significant amount of smaller substrate fragments behind C omments from Mark Berrigan, ( DOACS) who was involved in the suggested that the particular batch of mined material used in the War of lesser quality than the average mined material used in reef restorations. The lesser quality of the mined material in addit ion to combined effects of wave action and prolonged wetting (submersion) of the substrate, was areas was important to note because they effectively decreased the amount of mined material available for recruitment, thus likely biasing the field data in favor of the fresh shell substrate. The remaining mined material rubble did not provide sufficient surface area to support the establishment of larger sized oyster; the end result was that the fresh shell had significantly greater spat abundances (6 month 1 Way ANOSIM, R = 0.241) and greater spat growth ( Figure 10 ). ANOS IM analysis of the monthly oyster abundances ( Table 1 ) confirmed the observations of greater spat recruitment on the fresh shell. The monthly epifaunal abundance AN OSIM results indicate that the community compositions of the two substrates became more similar by the end of the study ( Table 1 ). This trend is most like ly the res ult of continual reef development that occurred on both substrates over the course of the study. The reef began with two, distinct veneer substrates, developing differing epifaunal communities. However, through continual

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44 oyster settlement and growth on b oth substrates, the epifaunal communities of the two experimental substrates converged to a more homogenous reef community as the reef matured. Experimental Tray Analysis T he two fresh shell treatments yielded the highest total live oyster abundances ob served per treatment by the end of the study. The live oyster abundances from highest to lowest were: 1) Fresh Shell = 1,794, 2) Fresh Shell with spat = 1,408, 3) Mined Material with spat = 1158 and 4) Mined Material = 916. The fact that both the fresh s hell treatments had the largest total live spat counts for the study indicates a potential preference for the fresh shell over the mined material. As addressed above, the seeming oyster preference of the fresh shell was likely biased due to the instabilit y of mined material ( Figure 22 ) Contents of the experimental trays came from the same source used to construct the reef. Mined material treatments f rom the December analysis contained high levels of substrate fragments, shell fragments, and disarticulated valves, demonstrating the same weakness noted in the field observations. The instability of the mined material combined with the aforementioned sed iment and algae induced anoxic stresses experienced at the reef base were likely the cause of the reduced oyster recruitment in both of the mined material treatments. In spite of the high preset oyster mortality levels, all measures but the bivalve sp ecies abundance reported significant differences between treatments in the March collection ( Table 4 ). The 1 Way ANOSIM results regarding oyster abundance between t reatments showed that all pairwise treatment combinations were significantly different

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45 (R = 1, p= 0.1) except the between the two spat treatments and the two non spatted treatments. Similar results for the epifaunal measures suggest the significant differ ences detected between the treatments were due to the presence of the preset oyster spat rather than the difference in substrate. This inference is further supported by the results of the Figure 22 : Examples of mined material s ubstrate samples after spontaneous fracturing during lab analysis. June collection. The insignificant global R values for all of the measures taken in June corresponded with the near total mortality of oysters in all treatments and the declining average of articulated oyster abundance (both alive and dead) in the preset treatments. The significant increases in the average species richness ( Figure 14 ) (R = 0.44) and epifaunal abundance (R = 0.541) between March and September 2006 therefore were not likely influenced by the presence of live oysters. The species richness of the trays increased because each treatment partially converted from a hard bott om substrate to a soft bottom mud flat due to the continual sediment loading. Consequently, some sessile species, e.g. Balanus sp ., abundances decreased while the more sediment tolerant species colonized the trays. Though not statistically significant, the increase in the average live oyster abundance in September ( Figure 13 and Figure 15 A D) is important to note

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46 because it suggests improved bottom conditions, in spite of the high sedimentation rate. The sediment accrued at the reef base was not analyzed in the experiment. However, in September I did not detect evidence for anoxic stress, which may account for the increase in live oyster density observed. Due to the effects of the sediment loading on the experimental trays, the data obtained from the first, second, and third quarterly collection reveal little about how the different substrates affect oyster and epifaunal colonization. It is reasonable to conclude that any initial differences that existed between treatments were grossly overwhelmed by similar sediment stresses. Thus the similari ties detected between the three collections were likely related to the environmental stresses shared by all the treatments. In an attempt to diminish the influence of sedimentation on the treatments, the last remaining 12 trays were suspended on cinder bl ocks during the September collection. Increasing the elevation of the trays not only removed them from areas of high sedimentation, but also exposed them to increased current velocities, which washed sediment off the top of the trays. Analysis of the Dec ember collection showed a marked increase in live oyster and epifaunal densities, and in species richness compared to the previous three collections ( Figure 13 and Figure 14 ). Though ANOSIM analyses reported no significan t similarity in species richness between treatments in any but the first collec tion ( Table 4 ), bar grap h s of the average species richness values for each treatment ( Figure 14 ) suggest the epifaunal community was converging toward greater similarity throughout the study Cluster analyses of live oyster abundance ( Figure 16 ) and the total epifaunal assemblage ( Figure 18 ) showed more significant clustering between collection periods than b etween treatments. A 2 D MDS plot of the species

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47 richness values of the treatment replicates ( Figure 17 ) revealed a similar pattern of sample clusteri ng between collection periods than the treatments, converging through time toward the December samples. The majority of the overall 1 way ANOSIM results for the variables considered are only significantly dissimilar (p <0.01) when the collection period fa ctor is included in the analysis (see Table 3 ). Even after reducing the sediment stress on the December trays, the lack of dissimilarity between any of the measurem ents taken strongly implies that there would be strong similarities between the communities in any future collections. Anderson and Underwood (1994) found similar results in a fouling community study involvin g the Sydney rock oyster, S. commercialis Though the initial fouling assemblages on man made substrates were very different during the first few months, by 12 months time the assemblages had converged toward a single type of assemblage. Anderson and Und erwood suggest that this convergence was mostly a result of the rapid settlement and growth of the oysters; the initially different substrates transformed into similar substrates due to oyster overgrowth. Though the experimental trays in the current study did not show statistically significant increase s in spat settlement and growth once removed from the sediment between September and December 2006, the similar community convergence trends are a result of both increased oyster density and inc reased homogeneity of the associated biota Large sediment volumes in the December trays during analysis suggest that while oyster reef and mud dwelling species. The res ults from the December collection probably better reflect the potential reef development that would have occurred in the trays if not for the significant sediment deposition Despite the fact that the experimental trays were

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48 augmented with mud dwelling sp increasing species richness levels recorded were ultimately a result of the oyster reef, not the sediment. There was an increase in species richness because the oyster reef itself facilitated the crea tion of the soft bottom habitat at its base and in the trays. Without the reef and the structure it provides, the same species richness would not have occurred.

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49 CONCLUSION This study faced design problems from the very beginning. Before even the first quarterly collection, unexpected variables such as a high sediment ation and algal accumulation and die off had negatively impacted the experimental design. The effect of preset oysters on natural oyster recruitment and the developing macrofaunal ass emblage was left undetermined because the substrate burial and anoxic bottom conditions killed the majority of the preset oysters before any data were collected. Between January and September sediment burial convert ed the substrates in the experimental tr ays from hard bottom to soft bottom habitats. Only following the elevation of the final set of experimental trays from the sediment were positive results yielded from the substrate treatments. In contrast, the monthly field observations were mostly unaffe cted by the sedimentation rate on the reef face and yielded some of the more informative data concerning the reef. Data strongly suggest that fresh oyster shell was the preferred substrate for oyster recruitment and community development, but the instabil ity of the mined material substrate likely biased the observations. Had a more stable mined material been used, it is probable that the sampling would have shown the mined material to perform well as an alternative oyster cultch

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50 Though this was only a one year study the observed species succession of the oyster reef yielded some very useful information. The study pointed out that the source and makeup of the material used in a reef project ought to be carefully considered beforehand Also, the results of this study show ed that the future reef projects ought to consider the influence a reef structure will have on environmental variables such as local water flow and sediment transport The diversity and habitat use graduall y increased as the reef community developed and the reef matured into rich oyster reef habitat useful is the list of r eef inhabiting species that was compiled ov er the course of this study The epifaunal community data from this study provides one of the more comprehensive species lists of oyster reefs in the Tampa Bay area

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51 REFERENCES Anderson, M. J. & A. J. Underwood. 1994. Effects of substratum on the recruitment and development of an intertidal estuarine fouling assemblage. Journal of Experimental Marine Biology and Ecology 184: 217 236. Bartol, I. K. & R. Mann. 1999. Small scale patterns of recruitment on a constructed intertidal reef: the role of spatial refugia. In: M.W. Luckenbach, R. Mann & J. A. Wesson, editors. Oyster Reef Habitat Restoration: A Symposium of Approaches. Gloucester Point, Virginia: Virginia Institute of Marine Science Press, pp. 159 170. Bonsdorff, E., A. Norkko & E. Sandburg. 1995. Structuring zoobenthos: the importance of predation, siphon cropping, and physical disturbance. Journal of Ex perimental Marine Biology and Ecology 192: 125 144. Breitburg, D. L. 1999. Are three dimensional structure and healthy oyster population the keys to an ecologically interesting and important fish community? In: M.W. Luckenbach, Mann, R. & Wesson, J. A., e ditors. Oyster Reef Habitat Restoration: A Symposium of Approaches. Gloucester Point, Virginia: Virginia Institute of Marine Science Press, pp. 239 250. Breitburg, D. L., L. D. Coen, M. W. Luckenbach, R. Mann, M. Posey & J. A. Wesson. 2000. Oyster reef res toration: convergence of harvest and conservation strategies. Journal of Shellfish Research 19: 371 377. Brenchley, G. A. 1982. Mechanisms of spatial competition in marine soft bottom communities. Journal of Experimental Marine Biology and Ecology 60: 17 33. Carriker, M. R. & P. M. Gaffney. 1996. A catalogue of selected species of living oysters (Ostreacea) of the world. In: V.S. Kennedy, R.I. Newell & A.F. Ebele, editors. The Eastern Oyster, Crassostrea virginica College Park, Maryland: Maryland Sea Gra nt College Publication, pp. 1 18.

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52 Clark, D., D. Meyer, A. Veishlow & M. LaCroix. 1999. Dredged material as a substrate for fisheries habitat establishment in coastal waters. In: M.W. Luckenbach, R. Mann & J. A. Wesson, editors. Oyster Reef Habitat Restorat ion: A Symposium of Approaches. Gloucester Point, Virginia: Virginia Institute of Marine Science Press, pp. 305 314. Clarke, K. R. & R. N. Gorley, 2006. PRIMER v6: User Manual/Tutorial. PRIMER E Ltd., Plymouth. Coen, L. D., D. M. Knott, E. L. Wenner, N. H. Hadley, A. H. Ringwood & M. Y. Bobo. 1999a. Intertidal oyster reef studies in South Carolina: Design, sampling, and experimental focus for evaluating habitat value and function. In: M.W. Luckenbach, R. Mann & J. A. Wesson, editors. Oyster Reef Habitat Res toration: A Symposium of Approaches. Gloucester Point, Virginia: Virginia Institute of Marine Science Press, pp. 133 158. Coen, L. D., M. W. Luckenbach & D. L. Breitburg. 1999b. The role of oyster reefs as essential fish habitat: a review of current knowle dge and some new perspectives. American Fisheries Symposium 22: 438 454. Devakie, M. N. & A. B. Ali. 2002. Effective use of plastic sheet as substrate in enhancing tropical oyster (Crassostrea iredalei Faustino) larvae settlement in the hatchery. Aquacult ure 212: 277 287. Emerson, C. W. 1989. Wind stress limitations of benthic secondary production in shallow, soft sediment communities. Marine Ecology Progress Series 53: 65 77. Haywood, E. L., T. M. Soniat & R. C. Broadhurst III. 1999. Alternatives to cla m and oyster shell as cultch material for eastern oysters. In: M.W. Luckenbach, R. Mann & J. A. Wesson, editors. Oyster Reef Habitat Restoration: A Symposium of Approaches. Gloucester Point, Virginia: Virginia Institute of Marine Science Press, pp. 295 304 Hinchey, E. K., L. C. Schaffner, C. C. Hoar, B. W. Vogt & L. P. Batte. 2006. Responses of estuarine benthic invertebrates to sediment burial: the importance of mobility and adaptation. Hydrobiologia 556: 85 98. Hoffman, W. E., M. J. Durako & R. R. Lewis II. 1985. Habitat Restoration in Tampa Bay. In: Tampa Bay Area Scientific Information Symposium, No. 65, Rep. Fla. Sea Grant Program, Tampa Bay, FL.

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53 Jones, C. G., J. H. Lawton & M. Shachak. 1994. Organisms as ecosystem engineers. Oikos 69: 373 386. Kilg en, R. H. & R. J. Dugas. 1989. The ecology of oyster reefs on the northern Gulf of Mexico: an open file report. In: NWRC Open File, 89 03, Fish and Wildlife Service, Minerals Management Service, U.S. Department of the Interior. Langefoss, C. M. & D. Maure r. 1975. Energy partitioning in the American oyster, Crassostrea virginica (Gmelin). Proc. Natl. Shellfish Assoc 65: 20 25. Lehnert, R. L. & D. M. Allen. 2002. Nekton use of subtidal oyster shell habitat in a southeastern U.S. estuary. Estuaries 5: 1015 1024. Lenihan, H. S. 1999. Physical biological coupling on oyster reefs: how habitat structure influences individual performance. Ecological Monograph 69: 251 275. Lenihan, H. S. & C. H. Peterson. 1998. How habitat degradation through fishery disturbanc e enhances impacts of hypoxia on oyster reefs. Ecological Applications 8: 128 140. Luckenbach, M. W., L. D. Coen, P. G. Ross Jr. & J. A. Stephen. 2005. Oyster reef habitat restoration: relationships between oyster abundance and community development on tw o studies in Virginia and South Carolina. Journal of Coastal Research 40: 64 78. Newell, R. I. E. 1988. Ecological changes in the Chesapeake Bay: are they the result of the overharvesting of the American Oyster, Crassostrea virginica ? In: Understanding th e estuary: advances in Chesapeake Bay research, Publication 129 CBP/TRS 24/88, Chesapeake Bay Consortium, Gloucester Point, Virginia. design criteria in constructed oyster ree fs: Oyster recruitment as a function of substrate type and tidal height. Journal of Shellfish Research 19: 387 395. Ortega, S. & J. P. Sutherland. 1992. Recruitment and growth of the Eastern Oyster, Crassostrea virginica in North Carolina. Estuaries 15: 158 170.

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54 Peachy, R. B. J. 2003. Tributylin and polycyclic aromatic hydrocarbon levels in Mobile bay, Alabama: a review. Marine Pollution Bulletin 46: 1365 1371. Peterson, C. H., J. H. Grabowski & S. P. Powers. 2003. Estimated enhancement of fish producti on resulting from restoring oyster reef habitat: quantitative valuation. Marine Ecology Progress Series 264: 251 266. Posey, M. H. 1986. Changes in a benthic community associated with dense beds of a burrowing deposit feeder, Callianassa californiensis M arine Ecology Progress Series 31: 15 22. Powell, E. N. & K. A. Ashton Alcox. 2004. A comparison between a suction dredge and a traditional oyster dredge in the transplantation of oysters in Delaware Bay. Journal of Shellfish Research 23: 803 823. Priest III, W. I., J. Nestlerode & C. W. Frye. 1999. Use of dredged material for oyster habitat creation in coastal Virginia. In: M.W. Luckenbach, R. Mann & J. A. Wesson, editors. Oyster Reef Habitat Restoration: A Symposium of Approaches. Gloucester Point, Virgi nia: Virginia Institute of Marine Science Press, pp. 283 294. Roegner, G. C. & R. Mann. 1995. Early recruitment and growth of the American oyster, Crassostrea virginica (Bivalvia: Ostreidea) with respect to tidal zonation and season. Marine Ecology Progres s Series 117: 91 101. Saoud, I. G. & D. B. Rouse. 2000. Evaluating sediment accretion on a relic oyster reef in Mobile Bay, Alabama. Journal of Applied Aquaculture 10: 41 49. Shumway, S. 1996. Natural environment factors. pp. 467 513. In: V.S. Kennedy, R .I. Newell & A.F. Ebele, editors. The Eastern Oyster, Crassostrea virginica Maryland Sea Grant College Publication, College Park, Maryland. Tamburri, M. N., R. K. Zimmer faust & M. L. Tamplin. 1992. Natural sources and properties if chemical inducers medi ating settlement of oyster larvae: A re examination. Biological Bulletin 183: 327 338. Thomsen, M. S. & K. J. McGlathery. 2006. Effects of accumulations of sediments and drift algae on recruitment of sessile organisms associated with oyster reefs. Journal of Experimental Marine Biology and Ecology 328: 22 34.

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55 Thomsen, M. S., B. R. Silliman & K. J. McGlathery. 2007. Spatial variation in recruitment of native and invasive sessile species onto oyster reefs in a temperate soft bottom lagoon. Estuarine, Coasta l and Shelf Science 72: 89 91. Tolley, S. G., A. K. Volety, M. Savarese, L. D. Walls, C. Linardich & E. M. Everham III. 2006. Impacts of salinity and freshwater inflow on oyster reef communities in Southwest Florida. Aquatic Living Resources 19: 371 387. Turner, E. J., R. K. Zimmer faust, M. A. Palmer & N. D. Pentcheff. 1994. Settlement of oyster ( Crassostrea virginica ) larvae: Effect of water flow and water soluble chemical cues. Limnology and Oceanography 39: 1579 1593. Whitlach, R. B. & R. W. Osman. 1 999. Oyster reefs as metapopulations: approaches for restoring and managing spatially fragmented habitats. In: M.W. Luckenbach, R. Mann & J.A. Wesson, editors. Oyster Reef Habitat Restoration. A Symposium of Approaches. Gloucester Point, Virginia: Virgini a Institute of Marine Science Press, pp. 199 212. Wilson Jr., W. H. 1981. Sediment mediated interactions in a densely populated infaunal assemblage: the effects of the polychaete Abarenicola pacifica Journal of Marine Research 39: 735 848.

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56 BIBLIOGRAPHY Abbot, R. T., 1954. American seashells. Litton Educational Publishin g, Inc, New York. Abele, L. G. & W. Kim, 1986. An Illustrated Guide to the marine decapod crustaceans of Florida. Florida State University Press. Dawes, C. J., 1967. Marine algae in the vicinity of Tampa Bay, Florida. University of South Florida, Tampa Bay. Coast marine life. Gulf Publishing Company, Houston. Hendler, G., J. Miller, E. John, D. Pawson, L. David & P. M. Kier, 1995. Sea stars, sea urchins, and allies: Echin oderms of Florida and the Caribbean. Smithsonian Institution Press, Washington. Hoese, H. D. & R. H. Moore, 1998. Fish of the Gulf of Mexico, Texas, Louisiana and adjacent waters. Texas A&M University Press, College Station. Humann, P., 1999. Reef creatu re identification: Florida, Caribbean, Bahamas. New World Publications, Jacksonville. Kaplan, E. H., 1988. A field guide to Southeastern and Caribbean seashores: Cape Hatteras to the Gulf Coast, Florida, and the Caribbean. Houghton Mifflin Company, Boston Littler, D. S., M. M. Littler, K. E. Bucher & J. N. Norris, 1989. Marine plants of the Caribbean, a field guide from Florida to Brazil. Smithsonian Institution Press, Washington, D.C. Tolley, S. G. & A. K. Volety. 2005. The role of oysters in habitat us e of oyster reefs by resident fish and decapod crustaceans. Journal of Shellfish Research 24: 1007 1012. Tolley, S. G., A. K. Volety & M. Savarese. 2005. Influence of salinity on the habitat use of oyster reefs in three southwest Florida estuaries. Journ al of Shellfish Research 24: 127 137.

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57 Voss, G. L., 1976. Seashore life of Florida and the Caribbean. E.A. Seemann Publishing, INC., Miami. Williams, A. B., 1984. Shrimps, lobsters, and crabs of the Atlantic Coast of the Eastern United States, Maine to F lorida. Smithsonian Institutional Press, Washington, D.C.

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58 APPENDICES

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59 Appendix A: Post Construction Water Quality Surveys Appendix A 1: Post c onstruction 24 hour w ater q uality s urvey, w indward f ace : m easurements were taken every tw o hours at the same loca tion on both sides of the reef ; ( E) indicates Ebb Tide, (F) indicates Flood Tide. Salinity values calculated from conductivity measurements 24hr Water Quality Survey Windward Side Sample Time Tide Temperature ( 0 C) Calculated S alinity (ppt) Turbidity (Ntu) Total Dissolved Solids (g/l) DO (mg/l) 11:15 AM E 22.8 32.7 63 29 >8 1:15 PM E 23.3 29.3 180 26 >8 3:15 PM F 23.6 29.7 41 26 >8 5:15 PM E 23.8 29.4 110 26 >8 7:15 PM E 24.2 29.3 NA 26 >8 9:15 PM E 24 32.7 67 29 >8 11:15 PM E 23.9 35.3 11 31 >8 1:15 AM E 23.4 34.1 26 30 >8 3:15 AM F 23.8 NA 8 41 >8 5:15 AM F 22.7 32.3 99 29 >8 7:15 AM F 22.8 32.7 23 29 >8 9:15 AM F 23 33.1 25 29 >8 Mean 23.4 31.9 59.4 29.3 >8 Appendix A 2 : Post c onstruction 24 hour w ater q ualit y s urvey, l eeward f ace : m easurements were taken every two hours at the same location on both sides of the reef ; (E) indicates Ebb Tide, (F) indicates Flood Tide. Salinity valu es calculated from conductivity measurements 24hr Water Quality Survey Lee ward Side Sample Time Tide Temperature ( 0 C) Calculated Salinity (ppt) Turbidity (Ntu) Total Dissolved Solids (g/l) DO (mg/l) 11:15 AM E 23.8 31.6 44 29 >8 1:15 PM E 24.1 29.6 90 26 >8 3:15 PM F 24.5 29.6 NA 26 >8 5:15 PM E 24.3 29.6 NA 26 >8 7:15 PM E 24.1 29.3 NA 26 >8 9:15 PM E 23.9 33.7 8 30 >8 11:15 PM E 23.7 33.3 19 30 >8 1:15 AM E 23.5 35.3 16 31 >8 3:15 AM F 22.9 NA 12 43 >8 5:15 AM F 22.9 33.2 28 29 >8 7:15 AM F 23.1 33.2 17 29 >8 9:15 AM F 23 32.9 24 29 >8 Mean 23.7 31.9 28.7 29.5 >8

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60 A ppendix B : Species Abundance Table s Appendix B 1: Species abundances observed in each treatment replicate sample collected in March 2006. Treatment Replicates Fresh Shell Mined Material Fresh Shell with Spat Mined Material with Spat Observed Spec ies List 1 N 6 M 5 S 3 N 4 M 2 S 11 N 7 M 9 S 3 N 12 M 8 S Leuconoid Poriferan sp. 0 0 0 0 0 0 0 0 0 0 0 0 Cliona sp. (Colonial) 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Anemone sp. 0 0 1 1 0 0 0 0 0 0 1 0 Bugula neritina (Colonial) 0 0 0 0 0 0 0 0 0 0 0 2 Schizoporella unicornis (Colonial) 57 80 66 1 0 0 17 4 9 0 1 1 Common Jingle Shell Anomia simplex 0 0 0 1 0 0 27 12 0 0 0 0 Dwarf Glass haired Chiton Acanthochitona pygmaea 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Keyhole Limpet Diodora sp. 0 0 0 0 0 0 0 0 0 0 0 0 Common Atlantic Slipper Shell Crepidula fornicata 0 0 0 0 0 0 4 1 1 0 0 1 Spotted Slipper Shell Crepidula maculosa 0 0 0 0 0 0 0 0 0 0 0 0 Convex Slipper Shell Crepidula convexa 0 0 0 0 0 0 0 0 0 0 0 0 Spiny Slipper Shell Crepidula aculeata 0 0 0 0 0 0 0 0 0 0 0 0 Eastern Oyster Crassostrea virginica 0 0 0 0 0 0 47 193 26 50 136 119 Eared Ark Anadara notabilis 0 0 0 0 0 0 0 0 0 0 1 0 Scorched Mussel Brachidontes exustus 0 0 0 0 0 0 0 0 0 0 0 0 Cross Barred Venu s Chione cancellata 0 0 0 0 0 0 0 0 0 0 0 0 Lightning Venus Pitar fulminatus 0 0 0 0 0 0 0 0 0 0 0 0 Smith's Matesia Diplothrya smithii (smythii) 0 0 0 0 0 0 0 0 0 0 0 0 Montagu's Ervilia Ervilia nitens 0 0 0 0 0 0 0 0 0 0 0 0 Pointed Nut Clam Nuculana acuta 0 0 0 0 0 0 0 0 0 0 0 0

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61 Appendix B 1 (Continued) Atlantic Bay Scallop Argopecten irrandians concentricus 0 0 0 0 0 0 0 0 0 0 0 0 Southern Quahog Merc enaria mercenaria 0 0 0 0 0 0 0 0 0 0 0 0 Yellow Cockle T rachycardium muricatum 0 0 0 0 0 0 0 0 0 0 0 0 White Spotted Marginella Marginella guttata 0 0 0 0 0 0 0 0 0 0 0 0 Common Atlantic Marginella Marginella apicina 0 0 0 0 0 0 1 0 0 0 1 0 Ce rithium sp. 0 0 0 0 0 0 0 0 0 0 0 0 Tampa Drill Urosalpinx tampaensis 0 0 0 0 0 0 1 0 0 0 1 0 Common Atlantic Bubble Bulla striata 0 0 0 0 0 0 0 0 0 0 1 0 Banded Tulip Fasciolaria lilium 0 0 0 0 0 0 0 0 0 0 0 0 Very Small Dwarf Olive Olivella p usilla 0 0 0 0 0 0 0 0 0 0 0 0 Whitened Dwarf Olive Olivella dealbata 0 0 0 0 0 0 0 0 0 0 0 0 Dove Shell Anachis sp. 0 0 0 0 0 0 0 0 0 0 0 0 Impressed Odostome Odostomia impressa 0 0 0 0 0 0 0 0 0 0 0 0 Adam's Miniature Cerith Seila adamsi 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Gastropod sp. 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Orange Dorid sp. 0 0 0 0 0 0 0 0 0 0 0 0 Ice Cream Cone Worm Cistena gouldii 0 0 0 0 0 0 0 0 0 0 0 0 Plumed Worm (Debris Tube) Diopatra cuprea 0 0 0 0 0 0 0 0 0 0 0 0 Serpulid sp. 0 0 5 0 0 0 14 13 47 21 14 7 Sabellidae sp. 0 0 0 0 0 0 0 0 0 0 3 2 Fireworm Hermondice sp. 1 0 0 0 0 0 5 0 0 0 5 2 Unidentified Annelid sp. A 0 1 0 0 0 0 0 0 0 0 0 0 Unidentified Annelid sp. B 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Annelid sp. C 0 0 0 0 0 0 0 0 0 0 0 0

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62 Appendix B 1 (Continued) Unidentified Anneli d sp. D 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Terebellidae sp. 1 0 0 0 0 0 156 10 0 1 7 2 Oyster Leech Stylochus ellipticus 0 0 0 0 0 0 0 0 0 0 0 0 Ivory Barnacle Balanus eburneus 0 0 0 0 0 0 2 0 0 0 0 0 Stripped Barnacle Balanus amphitrite sp. 0 0 0 0 0 0 0 0 0 0 0 0 Blue Crab Callinectus sapidus 0 0 0 0 0 0 0 0 0 0 0 1 Porcelain Crab Petrolisthes armatus 0 0 0 0 0 0 50 7 1 1 12 3 Flat Mud Crab Eurypanopeus depressus 0 0 0 0 0 0 10 10 2 1 8 3 Common Mud Crab Panopeus obesus 0 0 0 0 0 0 0 0 0 0 0 0 Mud Crab Panopeus simpsonii 0 0 0 0 0 0 0 0 0 0 0 0 Narrow Mud Crab Hexapanopeus angustifrons 0 0 0 0 0 0 0 0 0 0 0 0 Hairy Crab Pilumnus sayi 0 0 0 0 0 0 0 0 0 0 0 0 Spider Crab Libinia dubia 0 0 0 0 0 0 0 0 0 0 0 0 Panopeus sp. 0 0 0 0 0 0 0 0 0 0 0 0 Unidenti fi able Hermit Crab sp. 0 0 0 0 0 0 0 0 0 0 0 0 Gammarus sp. 0 0 0 0 0 0 0 0 0 0 0 0 Corophium sp. 1 1 4 0 0 0 4 0 0 0 0 1 Grass Shrimp Palamonetes pugio 0 0 0 0 0 0 0 2 0 0 0 1 Pink Shrimp Penaeus duorarum 0 0 1 0 0 0 0 0 0 0 0 0 Banded Snapping Shrimp Alpheus armillatus 0 0 0 0 0 0 0 0 0 0 0 0 Big Claw Snapping Shrimp Alpheus heterochaelis 0 0 0 0 0 0 0 0 0 0 2 1 Green Snapping Shrimp Alpheus formosus 0 0 0 0 0 0 0 0 0 0 0 0 Coastal Mud Shrimp Upogeb ia afiinis 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Isopod sp. (Gribble) 0 0 0 0 0 0 0 0 0 0 0 0

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63 Appendix B 1 (Continued) Mud Brittle Star Amphioplus thrombodes 0 4 0 0 0 0 2 0 0 0 3 2 Harlequin Brittle Star Ophioderma appressum 0 0 0 0 0 0 0 0 0 0 0 0 Spiny Brittle Star Ophiothrix angulata 0 0 0 0 0 0 0 0 0 0 0 0 Green Sea Cucumber Thyonella gemmata 0 0 0 0 0 0 1 0 0 0 0 0 Pleated Sea Squirt Styela plicata 0 0 0 0 0 0 0 0 0 0 0 0 Styela canopus, a.k.a partida 0 0 0 0 0 0 0 0 0 0 0 0 Molgula manhattenensis 0 0 0 0 0 0 0 0 0 0 0 0 Botrylloides nigrum (Colonial) 0 0 0 0 0 0 0 0 0 0 0 0 Botyllus planus (Colonial) 0 0 0 0 0 0 0 0 0 0 0 0 Mangrove Tunicate Ecteinascidia tu rbinata 0 0 0 0 0 0 0 0 0 0 0 0 Diplosoma sp. 0 0 0 0 0 0 0 0 0 1 3 1 Coded Goby Gobisoma robustum 0 0 0 0 0 0 0 0 0 0 0 1 Speckled Worm Eel Myrophis punctatus 0 0 0 0 0 0 0 0 0 0 0 0 Gulf Toadfish Opsanus beta 0 0 0 0 0 0 0 0 0 0 0 0

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64 Appendix B 2: Species abundances observed in each treatment replicate sample collected in June 2006. Treatment Replicates Fresh Shell Mined Material Fresh Shell with Spat Mined Material with Spat Observed Species List 10 N 9 M 8 S 6 N 7 M 8 S 5 N 3 M 10 S 5 N 6 M 11 S Leuconoid Poriferan sp. 0 0 0 0 0 0 0 0 0 0 0 0 Cliona sp. (Colonial) 0 0 0 0 0 0 0 0 1 0 2 0 Unidentified Anemone sp. 0 0 0 0 0 0 0 0 0 0 0 0 Bugula neritina (Colonial) 3 3 0 0 0 6 0 0 0 0 2 0 Schizoporella unicornis (Colonial) 90 71 1 0 1 56 38 0 0 0 0 0 Common Jingle Shell Anomia simplex 0 126 1 6 5 41 1 1 2 1 12 0 Dwarf Glass haired Chiton Acanthochitona pygmaea 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Keyhole Limpet Diodora sp. 0 0 0 1 0 0 0 0 0 0 0 0 Common Atlantic Slipper Shell Crepidula fornicata 0 5 2 0 2 7 0 0 0 2 2 0 Spotted Slipper Shell Crepidula maculosa 0 8 3 1 1 4 0 0 1 1 0 0 Convex Slipper Shell Crepidula convexa 0 0 0 1 0 0 0 0 1 1 1 0 Spiny Slipper Shell Crepidula aculeata 0 0 0 0 0 0 0 0 0 0 1 0 Eas tern Oyster Crassostrea virginica 0 23 42 0 3 0 0 0 15 0 17 0 Eared Ark Anadara notabilis 0 0 0 1 0 0 0 0 0 0 2 0 Scorched Mussel Brachidontes exustus 0 0 0 0 1 0 0 0 0 0 0 0 Cross Barred Venus Chione cancellata 0 0 0 0 0 0 0 0 0 0 0 0 Lightnin g Venus Pitar fulminatus 0 0 0 0 0 0 0 0 0 0 0 0 Smith's Matesia Diplothrya smithii (smythii) 0 0 0 0 0 0 0 0 0 0 0 0 Montagu's Ervilia Ervilia nitens 0 0 0 0 0 0 0 0 0 0 0 0 Pointed Nut Clam Nuculana acuta 0 0 0 0 0 0 0 0 0 0 0 0

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65 Appendix B 2 (Continued) Atlantic Bay Scallop Argopecten irrandians concentricus 0 0 0 0 0 1 0 0 0 1 0 0 Southern Quahog Mercenaria mercenaria 0 0 0 0 0 0 0 0 0 0 0 0 Yellow Cockl e T rachycardium muricatum 0 0 0 0 0 0 0 0 0 0 0 0 White Spotted Marginella Marginella guttata 0 0 0 0 0 0 0 0 0 0 0 0 Common Atlantic Marginella Marginella apicina 1 4 2 3 0 5 3 0 0 6 3 0 Cerithium sp. 0 0 0 0 0 0 0 0 0 0 0 0 Tampa Drill Uros alpinx tampaensis 0 2 0 0 0 0 0 0 0 0 0 0 Common Atlantic Bubble Bulla striata 0 0 0 0 0 0 0 0 0 0 0 0 Banded Tulip Fasciolaria lilium 0 1 0 0 0 0 0 0 0 0 0 0 Very Small Dwarf Olive Olivella pusilla 0 0 0 0 0 0 0 0 0 0 0 0 Whitened Dwarf Olive Olivella dealbata 0 0 0 0 0 0 0 0 0 0 0 0 Dove Shell Anachis sp. 0 0 0 0 0 0 0 0 0 0 0 0 Impressed Odostome Odostomia impressa 0 0 0 0 0 0 0 0 0 0 0 0 Adam's Miniature Cerith Seila adamsi 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Gastropod sp. 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Orange Dorid sp. 0 0 0 0 0 0 0 0 0 0 0 0 Ice Cream Cone Worm Cistena gouldii 0 0 0 0 0 0 0 0 0 0 0 0 Plumed Worm (Debris Tube) Diopatra cuprea 0 0 0 0 0 0 0 0 0 0 0 0 Serpulid sp. 0 179 33 1 5 159 6 5 44 8 61 15 Sabe llidae sp. 0 35 3 0 2 17 0 0 0 0 12 0 Fireworm Hermondice sp. 0 1 0 0 0 0 0 1 0 2 2 0 Unidentified Annelid sp. A 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Annelid sp. B 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Annelid sp. C 0 0 0 0 0 0 0 0 0 0 1 0

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66 Appendix B 2 (Continued) Unidentified Annelid sp. D 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Tere bellidae sp. 0 0 2 5 1 0 6 3 0 5 21 14 Oyster Leech Stylochus ellipticus 0 0 0 0 0 0 0 0 0 0 0 0 Ivory Barnacle Balanus eburneus 16 545 57 5 50 410 0 0 122 6 167 11 Stripped Barnacle Balanus amphitrite sp. 0 122 8 1 39 132 0 0 17 0 0 0 Blue Crab Callinectus sapidus 0 1 0 0 0 0 0 0 0 0 0 0 Porcelain Crab Petrolisthes armatus 0 0 0 0 0 0 0 0 0 0 3 0 Flat Mud Crab Eurypanopeus depressus 0 8 1 0 3 7 0 0 1 1 6 0 Common Mud Crab Panopeus obesus 0 0 0 0 0 0 0 0 0 0 0 0 Mud Crab Panopeus si mpsonii 0 0 0 0 0 0 0 0 0 0 0 0 Narrow Mud Crab Hexapanopeus angustifrons 0 0 0 0 0 0 0 0 0 0 0 0 Hairy Crab Pilumnus sayi 0 0 0 0 0 0 0 0 0 0 0 0 Spider Crab Libinia dubia 0 0 0 0 0 0 0 0 0 0 0 0 Panopeus sp. 0 2 0 0 0 3 1 1 1 1 2 0 Unidenti fi a ble Hermit Crab sp. 0 0 0 0 0 0 0 0 0 0 0 0 Gammarus sp. 0 0 0 0 0 0 0 0 0 0 0 0 Corophium sp. 0 0 0 1 0 0 2 1 1 0 1 0 Grass Shrimp Palamonetes pugio 0 1 2 0 0 0 0 0 0 0 3 0 Pink Shrimp Penaeus duorarum 0 0 1 0 0 0 0 0 0 0 0 0 Banded Snapping Sh rimp Alpheus armillatus 0 0 0 0 0 0 0 0 0 0 0 0 Big Claw Snapping Shrimp Alpheus heterochaelis 0 0 0 0 0 1 0 0 0 0 2 0 Green Snapping Shrimp Alpheus formosus 0 0 0 0 0 0 0 0 0 0 0 0 Coastal Mud Shrimp Upogebia afiinis 0 0 0 0 0 0 0 0 0 0 0 0 U nidentified Isopod sp. (Gribble) 0 1 0 0 0 1 0 0 0 0 1 0

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67 Appendix B 2 (Continued) Mud Brittle Star Amphioplus thrombodes 0 5 0 0 0 3 0 0 0 1 4 0 Harlequin Brittle Star Ophioderm a appressum 0 0 0 0 0 0 0 0 0 0 0 0 Spiny Brittle Star Ophiothrix angulata 0 1 0 0 0 0 0 0 0 0 0 0 Green Sea Cucumber Thyonella gemmata 0 0 0 0 0 0 1 0 0 0 2 0 Pleated Sea Squirt Styela plicata 0 0 0 0 0 0 0 0 0 0 0 0 Styela canopus, a.k.a partid a 0 0 0 0 0 0 0 0 0 0 0 0 Molgula manhattenensis 0 0 0 0 0 0 0 0 0 0 0 0 Botrylloides nigrum (Colonial) 0 0 0 0 0 0 0 0 0 0 0 0 Botyllus planus (Colonial) 0 0 0 0 0 0 0 0 0 0 0 0 Mangrove Tunicate Ecteinascidia turbinata 0 0 0 0 0 0 0 0 0 0 0 0 Dipl osoma sp. 0 0 0 0 0 0 0 0 0 0 0 0 Coded Goby Gobisoma robustum 0 9 2 0 0 5 1 0 0 1 1 0 Speckled Worm Eel Myrophis punctatus 1 0 1 0 1 0 0 0 0 2 2 0 Gulf Toadfish Opsanus beta 0 0 0 0 0 0 0 0 0 0 1 0

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68 Appendix B 3: Species abundances observed in e ach treatment replicate sample collected in September 2006. Treatment Replicates Fresh Shell Mined Material Fresh Shell with Spat Mined Material with Spat Observed Species List 11 N 3 M 7 S 1 N 10 M 11 S 4 N 2 M 1 S 7 N 9 M 4 S Leuconoid Poriferan sp. 0 0 0 0 0 0 0 0 0 0 0 0 Cliona sp. (Colonial) 0 1 1 3 0 3 4 0 2 1 12 1 Unidentified Anemone sp. 0 0 0 0 0 0 0 0 0 0 0 0 Bugula neritina (Colonial) 0 0 0 0 0 0 0 0 0 0 0 0 Schizoporella unicornis (Colonial) 66 23 0 1 0 1 1 6 28 2 0 3 Common Jin gle Shell Anomia simplex 16 36 76 34 18 12 29 8 6 5 53 3 Dwarf Glass haired Chiton Acanthochitona pygmaea 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Keyhole Limpet Diodora sp. 0 0 0 1 0 0 0 0 0 1 0 1 Common Atlantic Slipper Shell Crepidula fornicata 4 57 66 44 10 0 39 28 26 13 28 7 Spotted Slipper Shell Crepidula maculosa 1 3 18 10 2 5 2 6 7 2 2 5 Convex Slipper Shell Crepidula convexa 0 0 0 0 0 0 0 0 0 0 0 0 Spiny Slipper Shell Crepidula aculeata 0 0 0 0 0 0 0 0 0 0 0 0 Eastern Oyster Cra ssostrea virginica 12 37 215 111 6 16 37 4 6 6 315 7 Eared Ark Anadara notabilis 2 1 6 1 2 2 3 5 2 3 6 0 Scorched Mussel Brachidontes exustus 2 6 1 7 6 2 0 4 8 2 10 3 Cross Barred Venus Chione cancellata 0 3 1 5 0 0 1 1 0 3 4 0 Lightning Venus Pitar fulminatus 0 0 1 1 0 0 1 1 0 0 0 0 Smith's Matesia Diplothrya smithii (smythii) 0 0 0 1 0 0 2 0 0 0 2 0 Montagu's Ervilia Ervilia nitens 0 0 0 0 0 0 0 0 0 0 1 0 Pointed Nut Clam Nuculana acuta 0 0 0 0 0 0 0 2 1 2 0 0

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69 Appendix B 3 (Continued) Atlantic Bay Scallop Argopecten irrandians concentricus 0 0 0 0 0 0 0 0 0 0 0 0 Southern Quahog Mercenaria mercenaria 0 0 0 0 0 0 0 0 0 0 0 0 Yellow Cockle T rachy cardium muricatum 0 0 0 0 0 0 0 0 0 0 0 0 White Spotted Marginella Marginella guttata 0 0 0 0 0 0 0 0 0 0 0 0 Common Atlantic Marginella Marginella apicina 2 1 2 0 2 2 2 2 0 0 1 3 Cerithium sp. 3 10 10 4 12 2 11 7 1 1 4 23 Tampa Drill Urosalpin x tampaensis 4 3 1 0 3 4 0 0 0 1 0 30 Common Atlantic Bubble Bulla striata 2 5 4 4 0 1 3 2 7 1 0 11 Banded Tulip Fasciolaria lilium 0 0 1 0 0 0 0 0 0 0 0 0 Very Small Dwarf Olive Olivella pusilla 2 0 0 8 0 0 3 16 3 13 8 2 Whitened Dwarf Olive O livella dealbata 1 0 0 1 5 0 0 0 0 0 2 0 Dove Shell Anachis sp. 0 2 2 13 3 1 4 3 10 6 3 0 Impressed Odostome Odostomia impressa 3 1 5 15 9 4 4 0 32 5 3 8 Adam's Miniature Cerith Seila adamsi 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Gastropod sp. 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Orange Dorid sp. 0 0 1 0 0 0 0 0 0 0 0 0 Ice Cream Cone Worm Cistena gouldii 0 0 0 0 0 1 1 0 0 2 0 0 Plumed Worm (Debris Tube) Diopatra cuprea 0 0 0 0 0 0 0 0 0 1 0 0 Serpulid sp. 28 44 215 60 32 28 44 17 4 10 243 30 Sabellidae sp. 36 142 379 279 96 87 238 64 49 102 330 41 Fireworm Hermondice sp. 1 12 7 7 3 3 13 9 1 5 5 4 Unidentified Annelid sp. A 0 0 0 1 0 0 0 0 0 0 0 0 Unidentified Annelid sp. B 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Annelid sp. C 0 5 0 2 1 0 10 7 2 3 5 5

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70 Appendix B 3 (Continued) Unidentified Annelid sp. D 0 0 0 0 0 0 2 4 2 5 0 3 Unidentified Terebellidae sp. 0 0 11 8 0 1 9 0 0 0 19 0 Oyster Leech Stylochus ellipticus 0 0 1 0 0 0 0 0 0 0 0 0 Ivory Barnacle Balanus eburneus 163 12 8 24 0 0 13 0 18 26 55 6 Stripped Barnacle Balanus amphitrite sp. 24 11 36 26 0 0 18 3 15 7 6 5 Blue Crab Callinectus sapidus 0 0 0 0 0 0 0 0 0 0 0 0 Porcelain Crab Petrolisthes armatus 2 3 12 10 2 0 14 6 0 1 35 1 Flat Mud Crab Eurypanopeus depressus 6 13 2 8 6 8 9 15 3 2 37 9 Common Mud Crab Panopeus obesus 0 5 2 3 0 1 1 3 1 1 11 0 Mud Crab Panopeus simpsonii 0 0 0 1 0 0 0 0 0 0 0 0 Narrow Mud Crab Hexapanopeus angustifrons 0 0 0 0 0 0 0 0 0 0 0 0 Hairy Crab Pilumnus sayi 0 0 0 1 0 0 0 1 0 1 0 0 Spider Crab Libinia dubia 0 2 1 1 0 0 1 0 0 0 2 0 Panopeus sp. 0 4 2 1 0 0 0 5 8 0 2 0 Unidentifiable Hermit Crab sp. 0 0 0 0 0 0 0 0 0 0 0 1 Gammarus sp. 0 0 0 0 0 0 0 0 0 0 0 0 Corophium sp. 0 0 0 1 0 0 0 0 7 0 0 0 Grass Shrimp Palamonetes pugio 0 0 4 0 0 0 9 2 2 0 2 1 Pink Shrimp Penaeus duorarum 0 0 0 0 0 0 3 0 0 0 0 0 Banded Snapping Shrimp Alpheus armillatus 0 11 9 6 0 0 0 7 0 2 9 0 Big Claw Snapping Shrimp Alpheus heterochaelis 1 14 13 10 6 4 12 11 12 11 7 9 Green Snapping Shrimp Alpheus formosus 0 0 1 0 0 0 0 0 0 0 0 0 Coastal Mud Sh rimp Upogebia afiinis 0 0 0 0 1 0 0 0 0 2 0 0 Unidentified Isopod sp. (Gribble) 2 1 0 1 0 0 2 0 4 1 0 0

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71 Appendix B 3 (Continued) Mud Brittle Star Amphioplus thrombodes 0 4 1 1 7 0 1 5 0 0 0 5 Harlequin Brittle Star Ophioderma appressum 0 1 0 1 0 0 0 0 0 0 0 0 Spiny Brittle Star Ophiothrix angulata 0 0 0 0 0 0 0 0 0 0 0 0 Green Sea Cucumber Thyonella gemmata 0 0 0 3 3 0 0 1 1 0 0 0 Pleated Sea Squirt Styela plicata 1 1 3 4 4 1 3 2 2 3 1 0 Styela canopus, a.k.a partida 0 0 1 1 0 0 0 0 3 0 2 0 Molgula manhattenensis 0 0 2 0 1 0 0 0 1 0 0 0 Botrylloides nigrum (Colonial) 0 0 0 0 0 0 0 0 0 0 0 0 Botyllus planus (Colonial) 0 0 0 0 0 0 0 0 0 0 0 0 Mangrove Tunicate Ect einascidia turbinata 0 0 0 0 1 0 0 0 0 0 1 0 Diplosoma sp. 3 4 8 13 0 2 10 3 0 0 7 0 Coded Goby Gobisoma robustum 2 2 2 2 0 0 3 3 6 3 1 0 Speckled Worm Eel Myrophis punctatus 0 0 0 0 1 2 0 1 0 0 0 3 Gulf Toadfish Opsanus beta 0 1 2 1 0 0 1 0 0 0 3 0

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72 Appendix B 4: Species abundances observed in each treatment replicate sample collected in December 2006. Treatment Replicates Fresh Shell Mined Material Fresh Shell with Spat Mined Material with Spat Observed Species List 12 N 2 M 4 S 9 N 12 M 5 S 6 N 12 M 8 S 1 N 10 M 2 S Leuconoid Poriferan sp. 0 0 0 0 0 0 0 0 4 0 0 0 Cliona sp. (Colonial) 2 0 0 3 17 1 2 13 0 0 13 0 Unidentified Anemone sp. 1 0 0 0 0 0 0 0 0 0 0 0 Bugula neritina (Colonial) 0 0 4 0 0 0 2 4 2 3 3 2 Schizoporel la unicornis (Colonial) 17 24 26 2 0 0 0 4 6 0 0 6 Common Jingle Shell Anomia simplex 33 110 0 28 21 38 64 118 144 10 42 19 Dwarf Glass haired Chiton Acanthochitona pygmaea 0 0 0 0 0 1 0 0 0 0 0 0 Unidentified Keyhole Limpet Diodora sp. 0 0 2 2 0 0 0 0 1 2 0 0 Common Atlantic Slipper Shell Crepidula fornicata 74 82 0 33 6 51 74 51 47 6 30 23 Spotted Slipper Shell Crepidula maculosa 4 12 9 4 1 8 5 6 8 0 0 2 Convex Slipper Shell Crepidula convexa 0 0 0 0 0 0 0 0 0 0 0 0 Spiny Slipper Shel l Crepidula aculeata 0 0 0 0 0 0 0 1 0 0 0 0 Eastern Oyster Crassostrea virginica 157 472 836 264 207 309 283 317 480 111 199 198 Eared Ark Anadara notabilis 3 2 11 13 5 9 11 9 15 2 4 5 Scorched Mussel Brachidontes exustus 1 7 0 4 0 1 1 3 0 0 3 0 Cross Barred Venus Chione cancellata 0 0 1 0 0 1 2 0 0 0 0 2 Lightning Venus Pitar fulminatus 0 0 0 0 0 0 0 0 0 0 0 0 Smith's Matesia Diplothrya smithii (smythii) 8 4 23 4 0 9 0 4 1 1 7 4 Montagu's Ervilia Ervilia nitens 0 0 0 0 0 0 0 0 2 0 0 0 Pointed Nut Clam Nuculana acuta 1 2 1 0 1 3 7 0 1 2 3 0

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73 Appendix B 4 (Continued) Atlantic Bay Scallop Argopecten irrandians concentricus 0 0 0 0 0 0 0 0 0 0 0 0 S outhern Quahog Mercenaria mercenaria 0 0 0 0 0 0 0 1 0 0 3 0 Yellow Cockle T rachycardium muricatum 0 0 0 2 0 0 0 0 0 0 0 0 White Spotted Marginella Marginella guttata 0 0 0 0 0 0 0 0 0 0 0 1 Common Atlantic Marginella Marginella apicina 3 0 1 2 1 0 0 1 2 0 1 1 Cerithium sp. 4 4 3 3 6 3 0 0 6 3 3 6 Tampa Drill Urosalpinx tampaensis 4 0 0 0 0 0 0 1 1 0 3 0 Common Atlantic Bubble Bulla striata 9 0 4 10 0 5 2 4 7 0 2 7 Banded Tulip Fasciolaria lilium 0 0 0 0 0 0 0 0 0 2 8 0 Very Small Dw arf Olive Olivella pusilla 16 2 9 18 4 9 5 0 4 5 0 3 Whitened Dwarf Olive Olivella dealbata 0 0 0 0 0 0 0 1 4 0 2 0 Dove Shell Anachis sp. 1 11 4 2 2 5 2 1 3 5 2 2 Impressed Odostome Odostomia impressa 0 0 0 2 4 10 18 0 9 0 0 6 Adam's Miniatur e Cerith Seila adamsi 0 3 1 2 4 1 2 1 9 4 3 0 Unidentified Gastropod sp. 1 4 6 4 4 0 9 7 16 9 11 2 Unidentified Orange Dorid sp. 0 0 1 0 0 0 0 0 0 0 1 0 Ice Cream Cone Worm Cistena gouldii 0 0 0 0 0 0 0 0 0 0 0 0 Plumed Worm (Debris Tube) Diopatr a cuprea 5 1 4 1 0 2 0 6 0 1 5 2 Serpulid sp. 323 375 329 374 387 196 1175 683 483 402 376 233 Sabellidae sp. 136 140 184 249 179 252 199 177 271 102 188 148 Fireworm Hermondice sp. 5 8 6 2 3 5 4 7 9 6 0 7 Unidentified Annelid sp. A 1 5 2 9 1 10 0 0 0 0 23 0 Unidentified Annelid sp. B 0 0 0 0 0 0 0 0 0 0 6 0 Unidentified Annelid sp. C 10 1 0 0 0 2 2 0 1 5 2 0

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74 Appendix B 4 (Continued) Unidentified Annelid sp. D 2 0 0 0 0 0 0 0 0 0 0 0 Unidentified Terebellidae sp. 5 9 2 17 13 1 25 15 3 2 20 3 Oyster Leech Stylochus ellipticus 1 1 0 1 0 1 0 0 1 1 0 2 Ivory Barnacle Balanu s eburneus 191 38 0 12 9 7 2 52 50 61 12 20 Stripped Barnacle Balanus amphitrite sp. 92 30 0 14 12 10 12 32 15 73 14 38 Blue Crab Callinectus sapidus 0 0 0 0 0 0 0 0 0 0 0 0 Porcelain Crab Petrolisthes armatus 20 29 2 35 16 18 19 33 2 5 73 4 Flat Mud Crab Eurypanopeus depressus 13 10 14 14 10 11 11 6 6 14 7 6 Common Mud Crab Panopeus obesus 7 5 0 10 6 8 7 8 1 6 6 6 Mud Crab Panopeus simpsonii 1 3 0 0 0 0 0 0 0 0 0 0 Narrow Mud Crab Hexapanopeus angustifrons 0 0 0 0 0 0 1 0 0 0 2 0 Hair y Crab Pilumnus sayi 0 0 0 0 0 0 0 0 0 0 0 2 Spider Crab Libinia dubia 3 1 0 0 0 0 3 0 1 3 1 0 Panopeus sp. 0 0 2 0 0 0 0 0 1 0 4 0 Unidentifiable Hermit Crab sp. 0 0 0 0 0 0 0 0 0 0 0 1 Gammarus sp. 40 13 21 26 22 20 13 49 7 18 15 9 Corophium sp. 15 11 12 17 9 8 12 35 5 12 10 2 Grass Shrimp Palamonetes pugio 10 17 5 8 29 26 24 26 25 2 22 21 Pink Shrimp Penaeus duorarum 2 4 3 4 3 5 0 0 0 5 9 1 Banded Snapping Shrimp Alpheus armillatus 2 2 4 2 4 4 0 1 3 0 0 0 Big Claw Snappin g Shrimp Alpheus heterochaelis 3 4 3 4 9 3 11 6 10 7 11 7 Green Snapping Shrimp Alpheus formosus 0 0 0 1 1 0 0 0 0 0 0 0 Coastal Mud Shrimp Upogebia afiinis 0 0 0 0 0 0 0 0 0 0 0 0 Unidentified Isopod sp. (Gribble) 12 15 14 9 14 4 5 32 4 11 0 10

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75 Appendix B 4 (Continued) Mud Brittle Star Amphioplus thrombodes 3 8 3 1 1 2 0 0 0 1 0 0 Harlequin Brittle Star Ophioderma appressum 0 0 0 0 0 0 0 0 0 0 0 0 Spiny Brittl e Star Ophiothrix angulata 0 0 0 1 1 1 1 0 0 0 0 4 Green Sea Cucumber Thyonella gemmata 0 0 0 0 0 0 2 0 0 0 0 1 Pleated Sea Squirt Styela plicata 7 26 33 19 5 36 30 30 75 0 48 0 Styela canopus, a.k.a partida 1 8 11 2 2 6 11 8 1 0 5 6 Molgula manh attenensis 2 12 23 11 0 12 0 22 0 0 6 12 Botrylloides nigrum (Colonial) 0 0 0 2 0 0 0 0 0 0 1 0 Botyllus planus (Colonial) 0 1 0 0 3 0 1 3 0 1 0 1 Mangrove Tunicate Ecteinascidia turbinata 0 0 0 0 0 0 0 0 0 0 0 0 Diplosoma sp. 0 0 0 0 0 0 0 0 0 0 0 1 Coded Goby Gobisoma robustum 5 7 0 0 1 1 1 2 8 1 0 6 Speckled Worm Eel Myrophis punctatus 0 0 0 0 0 0 0 0 0 0 0 0 Gulf Toadfish Opsanus beta 0 1 1 0 2 1 2 1 1 0 3 0