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Efecto del color y la altura en la preferencia de la oviposicin y la atraccin de insectos voladores
Effect of color and height on oviposition preference and attraction of volant insects
Abundance of volant insects and aquatic larvae was investigated in relation to vertical stratification and color of either required resource or oviposition site within the understory at the Finca Cataracta, in San Luis, Costa Rica. Three insect traps were hung per tree (three trees total used) at heights of 8 ft, 4 ft, and ground level. Each platform at the respective height consisted of four bottles that were green, red, black, or clear. Oviposition in different colors by Ephydridae and Psychodidae was affected by height. Both larvae were most abundant at the bottom level, though Ephydridae showed significant preference for black, while Psychodidae was more abundant in clear. The attraction of flying insects to color varied with height. Each Order was collected in large abundance at a specific color and height when the factors were juxtaposed (Diptera- top, black; Coleoptera- middle, clear; Hymenoptera- bottom, green). This study reveals the importance of visual cues in relation to height for oviposition behavior and volant insects.
Se investig la abundancia de insectos voladores y larvas acuticas en relacin a su estratificacin vertical y el color requerido para la oviposicin en el sotobosque de la Finca Catarata, en San Luis, Costa Rica.
Text in English.
Tropical Ecology 2009
Ecologa Tropical 2009
Comportamiento de oviposicin
t Monteverde Institute : Tropical Ecology
Effect of color and height on oviposition preference and attraction of volant insects Emily Daniel Department of Integrative Biology, University of California Berkeley ABSTRACT Abundance of volant insects and aquatic larvae was investigated in relation to vertical stratification and color of either required resource or oviposition site within the understory at the Finca Cataracta, in San Luis, Costa Rica. Three insect traps were hung per tree (three trees total used) at heights of 8 ft, 4 ft, and ground level. Each platform at the respective height consisted of four bottles that were green, red, black, or clear. Oviposition in different colors by Ephydridae and Psychodidae was affected by height. Both larvae were most abundant at the bottom level, tho ugh Ephydridae showed significant preference for black, while Psychodidae was more abundant in clear. The attraction of flying insects to color varied with height. Each Order was collected in large abundance at a specific color and height when the factor s were juxtaposed (Diptera top, black; Coleoptera middle, clear; Hymenoptera bottom, green). This study reveals the importance of visual cues in relation to height for oviposition behavior and volant insects. RESUMEN La abundancia de insectos volad ores y larvas acuticas fueron investigadas en relacin a su estratificacin vertical y color requerido para oviposicin en el sotobosque de la Finca Catarata en San Luis, Costa Rica. Tres trampas de insectos fueron colcadas en arboles a 8 pies, 4 pies y a l nivel del suelo. Cada plataforma contenia botellas de colores verde, rojo, negro, o transparente. La oviposicin de Ephydridae y Psychodidae fue afectadas por la altura. Ambas larvas fueron mas abundantes a nivel del suelo, pero Ephydridae tenia preferen cia por negro, mientras que Psychodidae fue mas abundante en colores transparentes. La atraccin de insectos voladores por los colores vari con la altura. Cada orden fue colectado en mayor abundancia en un color y una altura cuando ambos factores fueron t omados en cuenta. Este estudio demostr la importancia visual en relacin a la altura para la oviposicin y la atraccin de insectos voladores. INTRODUCTION Oviposition sites in nature vary broadly, including plant axils, Heliconia bracts, tank bro meliads, tree holes, dead logs, tires, and artificial containers (Yanoviak 2001). This variety of oviposition sites represents a wide assortment of colors: Heliconia bracts are red, bromeliads are shades of green, and tree holes and tires are brown or b lack. Color has long been recognized as one of the important physical factors in oviposition site selection (Bentley 1989). Wyeomia mitchelli and W. vanduzeei, both bromeliad specialists, have been shown to prefer yellow green oviposition sites. The lar val stages of W. ulocoma are typically found in Heliconia spp. bracts and studies observe these species to oviposit most in red containers (Frank 1986). Psychodidae are observed ovipositing in axil waters, bromeliad tanks, bamboo internodes and tree holes (Frank et al. 2004, Kitching 2001). Research on a wide variety of mosquito species has revealed many with more specific oviposition sites, such as Culiseta melanura only ovipositing in cedar or bay head swamp potholes and Deinocerites cancer larvae found only in flooded crab holes (Bentley 1989). These species also locate their specific sites through a complex integration of physical and chemical cues including color. Many studies exist
investigating mosquito color preference, yet few studies address ha bitat color and oviposition of other insects with aquatic larval stages (Yanoviak 2001). Visual stimulus is also a significant factor in oviposition with respect to vertical stratification (Stork and Grimbacher 2006). Many Insecta orders such as Diptera are canopy dwelling adults with ground dwelling larval forms (Zumbado 1999). These insects must search through the understory and on the ground in order to locate suitable habitats for laying eggs. Many suitable habitats exist at multiple stratification s. Bromeliads are mostly epiphytic, many in the high reaches of the canopy. Plants with large axils and tree holes are present from the canopy to the understory, while Heliconias are mainly in the lower understory. Dead logs and tires are located on the ground. Macroinvertebrates which specialize on particular oviposition sites would be expected to oviposit at heights in which the suitable habitats are found and rely upon visual cues such as color to find them. Similar to oviposition, visual cues a re necessary in order to find certain resources. Insects, such as Tephritid fruit flies, use vision for a variety of purposes besides oviposition, including location of habitat, food, and mating sites (Lopez Guillen et al. 2009). As in oviposition specia lization, specific sites of these resources are stratified from the canopy to the understory. Insecta are present within most trophic food web levels including herbivores and detritivores (Huffaker and Gutierrez 1999), thus I expect this diversity to caus e abundance in certain levels between the canopy and ground due to specialty. A previous study found all major orders across the vertical gradient with varying abundances (Dial et al 2006). Numerous other studies addressing Arthropoda, which looked at C ollembola (Rodgers and Kitching 1998), Coleoptera (Stork and Grimbacher 2006, Hirao et al. 2009), Hymenoptera (Vance et al. 2007), and Lepidoptera (Hirao et al. ) indicate assemblage specific abundance and diversity patterns within canopy and understory. T hough few studies address oviposition preference of non mosquito macroinvertebrates, I expect other insects will emulate the specialization exhibited by many mosquito species (Yanoviak 2001). I predict that certain orders will oviposit in a specific color of container at a specific height. Due to previous studies indicating vertical stratification by order (Dial et al 2006), I project the same results in this research. With the additional variable of color, I postulate specificity resulting from insect pr eference for particular resources. In this study I assessed the effect of color and height on oviposition preference and volant insects. METHODS For this study, three canopy trees were chosen at the Finca Cataracta in San Luis, Costa Rica. The trees are located behind the house of Doa Alicia, each within close enough proximity to one another for the canopies to intermingle. This compact spatial arrangement negated possible effects that tree species had on arthropod diversity as well as variance in u nderstory composition and forest type. Flight intercept traps from a previous CIEE study were utilized (Harp 2008). These traps were built by securing four 2 liter plastic soda bottles to a square piece of plywood (10.5 in 2 ). A rectangular opening (9 i n x 3.5 in) was cut in each bottle, 5 in from the top, to allow entrance by the Arthropoda. Each platform held four different
colored bottles (clear, green, red, and black) representing favorable oviposition sites: red for Heliconias green as Bromeliads, black for tree holes and dead logs, and clear as a control. These colors also apply to stratification due to resources: green as leaves, red for flowers or fruits, black as areas of dense foliage or decomposing matter, and clear as a control. The clear and green bottles were formed from these respective colors of plastic, thus only the red and black bottles were spray painted. Four holes were put 1 in from the rim of the opening to maintain water levels below capacity (Yanoviak 2001). Each tree held t hree traps at 8 ft, 4 ft, and ground level, giving a total of 36 bottles. The traps were placed in the trees by securing a rock to the end of the rope attached to the platform and throwing this rock over the desired branch. The platforms were pulled up w ith a tape measure attached to the top to ensure the correct height. Each rope end was tied down to keep the platforms at their respective heights. The trap that was hung 8 ft from the ground was strung over a horizontal branch near the center of the tre e. The trap at 4 ft was either on the same branch or the branch closest to that which held the first trap. The third trap was placed on the ground directly beneath the second trap. Securing the third trap to the second prevented the former from falling o ver. Before the traps were placed at the appropriate height, each bottle was filled with 1.5 cups of tap water from Doa Alicia's house, which is rainwater running from pipes located in the mountains. Also, a Piper sp. Stick, 2 in x 0.5 in, was placed in each bottle as an oviposition site (Yanoviak 2001). The stick was small enough that there was no effect on color appearance of the bottle. Traps were carefully pulled up into the trees to avoid water spillage. After eight days (5/6 5/14), water was coll ected in individually labeled containers. Arthropoda and larvae for each respective container were collected in individually labeled vials of 70% ethanol. Volant insects were identified to order and larvae to family. Larger arthropods were removed with tw eezers, while smaller Arthropoda and larvae were collected with an eye dropper. Chi squared tests were performed on all data in order to determine trends of oviposition for Ephydidae and Psychodidae as well as volant insect attraction and identified to O rder. Larger Arthropoda were removed with tweezers, while smaller Arthropoda and larvae were collected with an eye dropper. RESULTS Significantly larger abundance was observed within bottles at the bottom height. Over twice as many Ephydridae larva e were collected from black bottles (FIG. 1; N = 198) than red bottles (FIG. 1; N = 94), and only 2 in green. Ephydridae oviposition at different heights was affected by color (FIG. 1; CHI 2 = 746.60; df = 6; P > 0.0001). The greatest abundance of Psychod idae larvae was also collected from bottles in the bottom stratum (FIG. 2; N = 43). However, this family showed an overwhelming preference towards clear bottles (FIG. 2; N = 53). Psychodidae, similar to Ephydridae, exhibited selective oviposition at diff erent heights in specific colors (FIG. 2; CHI 2 =746.60; df=6; P> 0.0001). One Tabanidae larvae was collected in a red bottle at the top height. Due to the presence of only one larvae statistics and conclusions could not be applied.
FIGURE 1. Abundanc e of Ephydridae larvae observed at heights of 8 ft 4 ft and 0 ft in relation to color. Located in trees at the Finca Cataracta, San Luis, Costa Rica.
FIGURE 2. Abundance of Psychodidae larvae observed at heights of 8 ft 4 ft and 0 ft in relation to c olor in the trees at the Finca Cataracta, San Luis, Costa Rica. Coleoptera exhibited higher preference for clear at middle stratum (FIG. 3a; N = 8). Diptera showed highest preference for black within bottles at the highest level (FIG. 3b; N = 4). Only 2 Hemiptera individuals were collected, one in a red bottom bottle and another in a clear top bottle, and are therefore not discussed further (FIG. 3c). Hymenoptera individuals exhibited a preference for green bottles at the bottom height (FIG. 3d; N = 4) The green bottles attracted most individuals in the bottom stratifications (FIG. 3; N = 10), while the clear bottles collected more insects in middle stratifications (FIG. 3; N = 8). The insects preferred the black bottles in the top stratifications (F IG. 3; N = 9). Volant insects were attracted to colors differently in relation to height (CHI 2 =13.28; df=6; P< 0.05; FIG. 3). A variety of other insects were discovered in the bottles which arrived by walking rather than flight. However, due to only 18 individuals in this category, no statistics or conclusions could be performed.
FIGURE 3a d. Abundance of volant insect orders at 8 ft, 4 ft, and 0 ft as affected by color. a. Coleoptera b. Diptera c. Hemiptera d. Hymenoptera Located in trees at the Finc a Cataracta, San Luis, Costa Rica.
FIGURE 3. Abundance of volant insects at 8 ft, 4 ft, and 0 ft as affected by color. Located in trees at the Finca Cataracta, San Luis, Costa Rica. DISCUSSION As postulated, Ephydridae and Psychodidae demonstra ted oviposition preferences related to height and color (FIG. 1; CHI 2 = 746.60; df = 6; P > 0.0001). Larvae of these families were mainly found in bottom bottles and showed similarities in color attraction. The majority of Ephydridae larvae were collecte d from black bottles while Psychodidae were mainly found in the clear bottles. This is further proof of the importance of visual cues for Insecta in selection of suitable oviposition sites. No mosquitoes were collected from this study due to the addition of a Piper sp. stick as an oviposition site. Chemical components in Piper spp. are shown to deter mosquitoes (Dyer et al. 2003, Scott et al. 2004) Ephydridae larvae were mainly found in black and red bottles (FIG. 1; N (black) = 198, N (red) = 94). The se results concur with previous studies which revealed a majority of Diptera larvae in black cups (Yanoviak 2001). Ephydridae are known for their ability to inhabit a wide variety of habitats. Larvae feed on a variety of substrates including cyanobacteri a, algae, detritus, and decomposing carcasses. However, less than 10% of their species have been studied with respect to life cycles, thus this high significance may reflect a previously unknown bias of Ephydridae towards darker larval development habitat s such as tree holes, logs, and tires (Foote 1995). The vast majority of Psychodidae larvae were specialized to one color, similar to Ephydridae, though these larvae preferred clear containers. Psychodidae ovipositon in
relation to color was tested for in a previous study by Yanoviak and the majority discovered in black bottles (Yanoviak 2001). However, in this earlier study, only cups in the gap area received oviposition. This dissimilarity can be explained by the absence of clear in Yanoviak's study, an d the height of all cups at about 3 ft (Yanoviak 2001). Results from this study revealed only 6 individuals in clear bottles at the middle stratum (4 ft), which is close to Yanoviak's trap height. Also, other studies have discovered Psychodidae in a vari ety of habitats including axil waters, bromeliad tanks, bamboo internodes and tree holes (Frank et al. 2004, Kitching 2001). This compilation of studies reveals a variety of oviposition sites for Psychodidae, indicating species specific preference or fami ly wide generality. Perhaps further studies could strengthen the conclusions from these studies that Psychodidae oviposition preference differs in color at varying heights and canopy cover. In accord with my predictions, my results indicate that volant in sects are attracted to color differently in relation to height (CHI 2 =13.28; df=6; P< 0.05; FIG. 3). According to Vance et al assemblage composition, especially at lower taxon levels, is the attribute most sensitive to vertical stratification (Vance et a l. 2007). The different stratifications observed between the orders may be explained by greater numbers of specific Genera from each order which are attracted to the particular colors used. Hymenoptera individuals mainly found in green bottom bottles (FIG 3d; N = 4) may be a reflection of species specific color preferences at certain levels. A strong bias towards green bottles (FIG. 3d; N = 4) was shown with Hymenoptera, possibly explained by their color receptors in the green, blue, and ultraviolet range (Reza and Parween 2006). Various Hymenopteran traits including: formation of leaf galls (Yamazaki and Ohsaki 2006), oviposition on leaves (Otim et al. 2008), preferentially parasitizing green host species (Langley et al. 2006), and partiality towards hos ts that live on leaves may also explain this bias towards green (Libbrecht et al. 2007). Coleoptera showed a large attraction to clear in the middle stratum (FIG. 3a; N = 8). Previous studies upon Coleoptera reveal either no color preference (Hoback et al. 1999), or are specific to species (Hausmann et al. 2004, Reddy et al. 2009). Also, true color vision has not yet been revealed for Coleopterans, thus this Insecta order may only rely upon varying shades of dark to light (Hausmann et al. 2004). Du e to the decrease of biomass within the middle levels of the understory, rather than indicating behaviors of locating suitable food sources, this overwhelming abundance may indicate other factors such as temperatures, moisture, and openness of this level i n the understory (Dial et al. 2006). When juxtaposing color and height data for Diptera, higher abundance was revealed in black bottles at the top stratification, though due to small sample size this difference in color preference isn't major (FIG. 3b; N = 4). This abundance of Diptera could indicate use of visual stimuli to locate food resources in the upper stratum. Most Diptera are herbivores, thus darker colors may be perceived as areas with denser foliage (Merrit et al. 2003). This attraction to da rker areas may also be behavior for protection from strong winds or predator avoidance (Stork and Grimbacher 2006). The graph in FIG. 3b indicated no Dipteran adults in the bottom stratum, even though most larvae were collected from the bottom bottles (FIG 1; FIG. 2). This validates the assertion of volant insects found in specific colors at other strata due to reasons other than oviposition.
Insect traps were placed in trees at the same site, thus this study may only reflect specific preferences of in sects in this area. A repetition of this study at different latitudes may strengthen the patterns observed in this study or reveal different preference results indicating unique specificity of insects within distinct areas. These further studies could al so include factors of canopy cover, different forest types, and a diversity of latitudes. Patterns beyond canopy, forest type, and latitude variance are necessary to investigate in regards to Psychodidae and Ephydridae due to the few studies available. T his research could investigate whether chemical cues or container shape play a role in suitable larval habitats. ACKNOWLEDGEMENTS Thank you to Fabricio at the University of Georgia Ecolodge for the use of the lab, materials, and wireless interne t. Also, I appreciate the help of the other staff members at the Ecolodge, especially Manuel, for aiding me in location of materials and a site for my project. I am grateful to Doa Alicia for allowing me to utilize the trees behind her house for my proj ect. Thank you very much to Pablo Allen for his availability and guidance through the many difficulties which arose during this project as well as his help with statistics. Finally, I appreciate the excellent aquatic insect identification skills of Pablo Allen and frog knowledge of Jos Carlos Caldern. LITERATURE CITED B ENTLEY M.D. 1989. Chemical ecology and behavioral aspects of mosquito oviposition. Annual Review of Entomology 34: 401 421. D IAL R.J., M.D.F. E LLWOOD E.C. T URNER AND W.A. F OSTER 20 06. Arthropod abundance canopy structure, and microclimate in a Bornean lowland tropical rainforest. Biotropica 38(5): 643 652. D YER L.A., C.D. D ODSON J.O. S TIREMAN III, M.A. T OBLER A.M. S MILANICH R.M. F INCHER AND D.K. L ETOURNEAU 2003. Synergistic ef fects of three Piper Amides on generalist and specialist herbivores. Journal of Chemical Ecology 29(11): 2499 2514. F RANK J.H. 1986. Bromeliads as ovipositional sites for Wyeomyia mosquitoes: form and color influence behavior. Florida Entomol. 69: 728 742 FRANK, J.H., S. SREENIVASAN, P. J. BENSHOFF, M. A. DEYRUP, G. B. EDWARDS, S. E. HALBERT, A. B. HAMON, M. D. LOWMAN, E. L. MOCKFORD, R. H. SCHEFFRAHN, G. J. STECK, M. C. THOMAS, T. J. WALKER AND W. C. WELBOURN. 2004. Invertebrate animals extracted from na tive Tillandsia (Bromeliales: Bromeliaceae) in Sarasota County, Florida. Florida Entomologist 87 (2): 176 185. F OOTE B.A 1995. Biology of Shore Flies. Annual Review of Entomology 40: 417 442. L OPEZ G UILLEN G., A. V IRGEN AND J. C. R OJAS 2009. Color pre ference of Anastrepha obliqua (Diptera, Tephritidae). Revista Brasileira de Entomologia 53(1): 157 159. H ARP C 2008. Stratification of volant insects and herbivore abundance in a Costa Rican cloud forest. In : Tropical Ecology and Conservation, Spring '08 CIEE, Monteverde: 36 46. H AUSMANN C., J. S AMIETZ AND S. D ORN 2004. Visual Orientation of Overwintered Anthonomus pomorum (Coleoptera: Curculionidae). Environ. Entomol. 33(5): 1410 1415. H IRAO T., M. M URAKAMI AND A. K ASHIZAKI 2009. Importance of the understory stratum to entomofaunal diversity in a temperate deciduous forest. Ecol Res 24: 263 272. H OBACK W.W., T. M. S VATOS S. M. S POMER AND L. G. H IGLEY 1999. Trap color and placement affects estimates of insect family level abundance and diversity in a Nebraska salt marsh. Entomologia Experimentalis et Applicata 91: 393 402. H UFFAKER C.B., AND A.P. G UTIERREZ (Eds.). 1999. Ecological entomology, 2 nd edition, John Wiley and Sons, Inc., New York, New York. K ITCHING R.L 2001. Food webs in phytotelma ta: "bottom up" and "top down" explanations for community structure. Annu. Rev. Entomol. 46: 729 60.
L ANGLEY S.A., K. J. T ILMON B. J. C ARDINALE AND A. R. I VES 2006. Learning by the parasitoid wasp, Aphidius ervi (Hymenoptera: Braconidae), alters indiv idual fixed preferences for pea aphid color morphs. Oecologia 150: 172 179. L IBBRECHT R., D. M. G WYNN AND M. D. E. F ELLOWES 2007. Aphidius ervi Preferentially Attacks the Green Morph of the Pea Aphid, Acyrthosiphon pisum. Journal of Insect Behavior 20( 1): 25 32. M ERRIT R.W., G.W. C OURTNEY AND J.B. K EIPER 2003. Diptera. In V.H. Resh and R.T. Carde (Eds.). Encyclopedia of Insects, pp. 85 91. Academic Press, San Diego, California. O TIM M., G. K YALO S. K YAMANYWA P. A SIIMWE J.P. L EGG M. G UERSHON AND D. G ERLING 2008. Parasitism of Bemisa tabaci (Homoptera: Aleyrodidae) by Eretmocerus mundus (Hymenoptera: Aphelinidae) on cassava. International Journal of tropical Insect Science 28 (3): 158 167. R EDDY G. V. P., Z. T. C RUZ AND A. G UERRERO 2009. Development of an efficient pheromone based trapping method for the banana root borer Cosmopolites sordidus. Journal of Chemical Ecology 35:111 117. R EZA A.M.S. AND S. P ARWEEN 2006. Differential preference of colored surface in Tribolium castaneum ISJ 3 : 84 88. R ODGERS D. J. AND R.L. K ITCHING Vertical stratification of rainforest collembolan (Collembola: Insecta) assemblages: description of ecological patterns and hypotheses concerning their generation. Ecography 21(4): 392 400. S COTT I.M., H. J ENSEN R. N ICOL L. L ESAGE R. B RADBURY P. S ANCHEZ V INDAS L. P OVEDA J.T. A RNASON AND B.J.R. P HILOGENE 2004. Efficacy of Piper (Piperaceae) extracts for control of common home and garden insect pests. Journal of Econ. Entomol. 97(4): 1390 1403. S TORK N. E. 2003. Biodiversity. In V.H. Resh and R.T. Carde (Eds.). Encyclopedia of Insects, pp. 85 91. Academic Press, San Diego, California. S TORK N.E. AND P.S. G RIMBACHER 2006. Beetle assemblages from an Australian tropical rainforest show that the canopy and the ground strata contribute equally to biodiversity. Proceedings of the Royal Society B 273: 1969 1975. V ANCE C.C., S.M. S MITH J.R. M ALCOLM J. H UBER AND M.I. B ELLOCQ 2007. Differences between forest type and vertical strata in the diversity and compo sition of hymenopteran families and mymarid genera in northeastern temperate forests. Environmental Entomology 36(5): 1073 1083. Y AMAZAKI K. AND N. O HSAKI 2006. Willow leaf traits affecting host use by the leaf gall forming sawfly. Population Ecology 48: 363 371. Y ANOVIAK S.P 2001. Container color and location affect macroinvertebrate community structure in artificial treeholes in Panama. The Florida Entomologist 84: 265 271. Z UMBADO M. 1999. Costa Rica Diptera, Instituto Nacional de Biodiversidad, Her edia, Costa Rica.