Vocal signaling in Henicorhina leucosticta (Troglodytidae)


previous item | next item

Citation
Vocal signaling in Henicorhina leucosticta (Troglodytidae)

Material Information

Title:
Vocal signaling in Henicorhina leucosticta (Troglodytidae)
Translated Title:
Señalización vocal en Henicorhina leucosticta (Troglodytidae)
Creator:
Fandel, Amber Desneige
Publication Date:
Language:
Text in English

Subjects

Subjects / Keywords:
Birds--Behavior ( lcsh )
Aves--Comportamiento ( lcsh )
Songbirds--Vocalization ( lcsh )
Aves que cantan--Vocalizacion ( lcsh )
Wrens ( lcsh )
Soterres ( lcsh )
Costa Rica--Puntarenas--Monteverde Zone
Costa Rica--Puntarenas--Zona de Monteverde
CIEE Spring 2009
CIEE Primavera 2009
Genre:
Reports

Notes

Abstract:
The communication between organisms has long been a fascination of mankind. Birds have been the subject of many such studies as they commonly have a large repertoire of communication techniques. This study examines the changes in several song measurements in order to determine the vocal responses of the breeding pairs to playbacks of various con-specifics. The researcher found that using measurements of low, high, center, maximum, and delta frequency of each pair before and after a playback, the pairs were easily differentiated from one another (Wilks != 0.61629, F20.455=3.57, p<0.001). Following playbacks, all pairs evaluated showed a decrease in maximum frequency of song phrases and a narrowing of frequency ranges (smaller delta frequency). Such changes in song characteristics may function to make the singing pair sound larger to intruders or to decrease call interference and the distance that the call travels. ( , )
Abstract:
La comunicación entre los organismos ha sido desde hace mucho tiempo de interés para la humanidad. Las aves han sido un tema de estudio en este campo debido a su gran variedad de repertorios utilizados para la comunicación. En este estudio examine los cambios en varias medidas de las vocalizaciones para determinar la respuesta vocal de las reproducciones de las parejas de varios conspecíficos.
Biographical:
Text in English.
Acquisition:
Born Digital

Record Information

Source Institution:
Monteverde Institute
Holding Location:
Monteverde Institute
Rights Management:
This item is licensed with the Creative Commons Attribution Non-Commercial No Derivative License. This license allows others to download this work and share them with others as long as they mention the author and link back to the author, but they can’t change them in any way or use them commercially.
Resource Identifier:
M39-00506 ( USFLDC DOI )
m39.506 ( USFLDC Handle )

Postcard Information

Format:
Book

Downloads

This item has the following downloads:


Full Text
xml version 1.0 encoding UTF-8 standalone no
record xmlns http:www.loc.govMARC21slim xmlns:xlink http:www.w3.org1999xlink xmlns:xsi http:www.w3.org2001XMLSchema-instance
leader 00000nas 2200000Ka 4500
controlfield tag 008 000000c19749999pautr p s 0 0eng d
datafield ind1 8 ind2 024
subfield code a M39-00118
040
FHM
0 041
eng
049
FHmm
1 100
Fandel, Amber Desneige
242
Sealizacin vocal en Henicorhina leucosticta (Troglodytidae)
245
Vocal signaling in Henicorhina leucosticta (Troglodytidae)
260
c 2009-05
500
Born Digital
3 520
The communication between organisms has long been a fascination of mankind. Birds have been the subject of many such studies as they commonly have a large repertoire of communication techniques. This study examines the changes in several song measurements in order to determine the vocal responses of the breeding pairs to playbacks
of various con-specifics. The researcher found that using measurements of low, high, center, maximum, and delta frequency of each pair before and after a playback, the pairs were easily differentiated from one another
(Wilks != 0.61629, F20.455=3.57, p<0.001). Following playbacks, all pairs evaluated showed a decrease in maximum frequency of song phrases and a narrowing of frequency ranges (smaller delta frequency). Such changes in song characteristics may function to make the singing pair sound larger to intruders or to decrease call interference and the distance that the call travels.
La comunicacin entre los organismos ha sido desde hace mucho tiempo de inters para la humanidad. Las aves han sido un tema de estudio en este campo debido a su gran variedad de repertorios utilizados para la comunicacin. En este estudio examine los cambios en varias medidas de las vocalizaciones para determinar la respuesta vocal de las reproducciones de las parejas de varios conspecficos.
546
Text in English.
650
Birds--Behavior
Songbirds--Vocalization--Costa Rica
Wrens
4
Aves--Comportamiento
Aves que cantan--Vocalizacin--Costa Rica
653
Tropical Ecology 2009
Vocal signaling
Ecologa Tropical 2009
Sealizacin vocal
655
Reports
720
CIEE
773
t Monteverde Institute : Tropical Ecology
856
u http://digital.lib.usf.edu/?m39.118



PAGE 1

Vocal Signaling in Henicorhina leucostict a Troglody tidae Amber Desneige Fandel Department of Biology, Occidental College ABSTRACT The communication between organisms has long been a fascination of mankind. Birds have been the subject of many such studies as they commonly have a large repertoire of communication techniques. This study examines the changes in several song measurements in order to determine the vocal responses of the breeding pairs to playbacks of various con specifics. The r esearcher found that using measurements of low, high, center, maximum, and delta frequency of each pair before and after a playback, the pairs were easily differen tiated from one another Wilks ðl = 0.61629, F 20.455 =3.57, p<0.001 . Following playbacks, all pairs evaluated showed a decrease in maximum frequency of song phrases and a narrowing of frequency ranges smaller delta frequency. Such changes in song characteristics may function to make the singing pair sounds larger to intruders or to decrease call interference and the distance that the call travels. RESUMEN La comunicación animal desde hace mucho tiempo ha sido de interés para l a humanidad. Las aves han sido un modelo de estudio en este campo debido a su gran variedad de repertorios utilizados para la comunicación. En este estudio examiné los cambios en varias medidas de las vocalizaciones para determinar la respuesta vocal de p arejas al playback de varios conspecíficos . Encontré que cuantificando la frecuencia más baja, la más alta, la central, la máxima y el rango de frecuencias, las parejas pueden ser identificadas acústicamente Wilks lambda= 0.61629, F 20.455 =3.57, p<0.001. Después de ser expuestos al playback, todas las parejas disminuyeron la frecuencia y estrecharon el rango de sus vocalizaciones. Estos cambios en la estructura de las vocalizaciones pueden funcionar para que la pareja que emite el canto aparente un mayor t amaño a los intrusos o para evitar la atenuación de la señal. INTRODUCTION Communication is a necessary trait in nearly all organisms and each goes about this behavior in a slightly different manner . The evolution of communication between individuals required a signaler, a signal, and a receiver Alcock 2005 . In order for the signal to fulfill its purpose that of communicating to another individual, the signaler must emit a signal that can be interpreted by the receiver. Ideally this signal, which c an be costly for the organism to produce, will elicit a certain response from the receiver Alcock 2005 , Laidre and Venrencamp 2008, Murray 1971, Orians and Willson 1964, Price et al. 2005 . Certain frequencies of sound are more difficult to produce than o thers and have different functions Fitzpatrick et al. 1977, Laidre and Venrencamp 2008, Price et al. 2005. From the perspective of the perspective of the evolution of effective communication in organisms, the examination of these characteristics is important. C ommunication in birds has been widely studied due to the relative ease of studying birds as well as the great knowledge of phylogeny, species assignment, and natural history of this taxon . Birds are known for the wide variety of their songs between species, ranging from very complex and beautiful to quite dissonant and unpleasant to completely atonal noi ses Fitzpatrick et al. 1977, Salaman et al. 2003, Skutch 1940. Extensive studies have been performed on many species to determine and characterize the function of their many songs and calls Fitz gerald et al.

PAGE 2

Fandel 2 1977, Kennedy and White 1996, Laidre and Venrencamp 2008 , Marshall Ball et al. 2006 . In nearly all species, the function of these vocalizations and the physical cues that go along with them serve to communicate territory boundaries, signal the opposite sex dur ing courtship, and communicate between individuals of a group Alcock, 2005, Laidre and Venrencamp 2008, Marshall Ball et al. 2006, Salaman et al. 2003, Skutch 1940 . All of the song s and calls vary according to individual, species, and location Dingle and Slabberkoorn 2008, Fitzpatrick et al. 1977 , Ryan and Brenowitz 1985 . Some bird species maintain stable territories throughout the year , which affects the function of songs Ashmole 1968, Fitzpatrick et al. 1977, Salaman et al. 2003, Skutch 1940 . For many species that have stable territories, communication is either to inform other individuals in surrounding territories the location of the territory of the sender or functions to maintain con tact between the other member s of the nest Alcock 2005 , Ashmole 1968, Fitzpatrick et al. 1977 . Continued interaction between the groups occupy ing surrounding territories is necessary for territorial signaling to be efficient and elicit the proper response from both sender and receivers McGregor 1993. In so me studies, it has been shown that t he presence o f a con specific has resulted in an increase in song complexity when compared to a spontaneous call from the sender Dunn 2006, Kennedy and White 1996, Laidre and Venrencamp 2008, Ryan and Brenowitz 1985 Maintaining contact among pairs is necessary between individuals in a pair during foraging , especially for those that forage in the undergrowth, as visibility is usually low in such areas Fitzpatrick et al. 1977, Salaman et al. 2003, Skutch 1940. Henicorhina leucosticta will be used i n order to illuminate the changes in song characteristics of bird pairs to 1 neighboring con specifics and 2 an unknown con specific . Previous studies have concluded that songs with lower frequencies indicate higher hostility then those of higher frequencies Morton 1977, and H. leucosticta are expected to lower frequency accordingly in response to territory invaders. The song character istics of Henicorhina leucosticta responses to playback have been relatively un examined . T his study aims to add to the lack of information on this species in the Monteverde area specifically . In order to examine song changes with the introduction of playb ack, i ndicative song characteristics such as low, hig h, maximum, and delta frequency will be examined. These qualities are related to the function of the song. MATERIALS AND METHODS Study site and species Henicorhina leucosticta , the Gray breasted wood wre n , is a comm on understory birds along the mountainside of the cloud forest in the Monteverde area of Costa Rica . Henicorhina leucosticta roos t in pairs, have distinct, constant territories throughout the year, and are usually found foraging within a short distance from their nest or roost site Fitzpatrick et al. 1977, Garrigues 2007, Salaman et al. 2003, Skutch 1940 . Tropical w rens are known to sing all year round desp ite seasonal and daily weather conditions Fitzpatrick et al. 1977, Garrigues 2007, Salaman et al. 2003, Skutch 1940. Henicorhina leucosticta also participates in duetting, in which both members of the pair sing Fitzpatrick et al. 1977, Garrigues 2007, Salaman et al. 2003, Skutch 1940 . This calling functions as both communication between the breeding pairs and signal territory locations between pairs in surrounding areas.

PAGE 3

Fandel 3 This study wa s performed between 155 0 and 1650 meters above sea level on the Sendero Principal behind the Estación Bioló gica Monteverde during April and May . The l ocations of the territories of 3 pairs of H. leucosticta were located by their territorial calling in the early morning 0500 0700 hours and locations were affirmed using approaches in r esponse to the Voices of Costa Rican Birds CD Gray Breasted Wood Wren playback. Playbacks were emitted using JBL portable speakers attached to an Apple iPod between the hours of 0500 and 0800 within the territory of the pair. Sampling methods and data ana lysis The researcher recorded the songs of H. leucosticta pairs with a Macally iVoicePro microphone attached to an Apple iPod. Spontaneous songs were recorded upon arrival to a territory from the pairs before the playback was emitted. After one minute of recording spon taneous song , the playback was produced to the pair while recording continued until up to two minutes after the playback if the pairs continued to sing following the playback . Recordings from the Voices of Costa Rican Birds CD were primaril y used for playback data . Five days of two recordings on each pair were gathered using playback. The researcher allowed between twenty minutes and one and a half hours between each recording of a pair to minimize the influence of the previous trial. The re cordings were then down loaded into Raven Interactive Sound Analysis Software. From these recordings, a portion of the song of each of two pair s were isolated and amplified. These amplification s of each of the two pair s were saved as a new file in Raven and then transferred back onto the iPod. Using the is olated song from the pairs, the selection of approximately one minute for each pair the time of the original CD playback was then used as the playback. Playbacks of the p airs whose songs were isolated only pair 2 and 4 were then used as playbacks for each of the three pairs. A total of six trials of each of the pair playbacks and ten trials of the CD playback were performed. All of the recordings obtained for the three p airs were entered in the Raven Software and analyzed. In order to determine the characteristics of each pair€s song and the differences in these characteristics of their songs before and after playback, song phrases were isolated within Raven . If possible , five song phrases before and after the playback were isolated for each recording from each pair and each trial . For every selection, measurements of high, low, center, max imum , and delta frequency were taken. Maximum frequency indicates the point where the most energy of the song phrase is concentrated. The other measures are those that indicate relative frequency and changes of characteristics throughout the song. To determine differences between pairs regardl ess of the playback , a Multivariate Discriminate Analysis was performed. In order to determine if there was a change in song characteristics before and after playbacks, paired t tests were used. RESULTS Analyses were performed to determine if the pairs were differentiable based on their song characteristics. Using the characteristics of low, high, center, max, and delta frequency, the pairs were easily differentiated from one another prior to playback Wilks ðl = 0.61629, F 2 0 .455 =3.57, p<0.001. It was also found that by examining these measurements taken on the songs of pairs before the playback, the pair c ould be determined with a 61.76% accuracy using a Multivariate

PAGE 4

Fandel 4 Discriminate Analysis. The song phrases isolated from each pair were examined to dete rmine if differ ences in characteristics before and after playback were present. General trends were observed, but these results were shown to be largely statis tically non significant t test , p>0.05. FIGURE 1. Average maximum frequency for H. leucostica pairs 2, 4, and 5 before and after playbacks from the Voices of Costa Rican Birds CD, pair 2 and pair 4. Error bars indicate standard error. B oth pair 2 and pair 5 lowered their maximum frequency in repsonse to playback Fig.1 . O nly pair 4, whose frequency before the playbacks was already quite a bit lower than pair 2 and 5, raised its frequency. Figure 2. Average delta frequency for H. leaucostica pairs 2, 4, and 5 before and after playback from the CD, pair 2, and pair 4. Error bars indicate standard error. Each of the pairs narrowed their range of frequ encies within their song phrases in response to Frequency Hz Pair Before After Frequency Hz Pair Before After

PAGE 5

Fandel 5 playback with the exception, again, being pair 4, who already had relatively low delta frequency. DISCUSSION This study aimed to examine the changes in certain song characteristics before and after a playback of a con specific was presented. Clear differences between the songs of individuals wit hin the few pairs of H. leucosticta were found. These findings indicate that though individual pairs are easily identifiable while they are spontaneously singing, once a playback is used , the songs are not differentiable between pairs. These findings sugge st that spontaneous singing of a pair performs a different function than the song that was recorded following a co n specific playback. P revious studies have shown that most birds have a large repertoire of calls that perform varying functions Fitzpatrick et al. 1977 . The function of the spontaneous calling can be reasonably concluded to be communication between the members of a territorial pair during foraging and mate location , and each pair has its own repertoire that it uses to communicate and ensure t he identity of its mate. The songs that can not be differentiated bet ween pairs upon presentation of a threat within the pair€s territory the presence of a con specific but not breeding partner call probably can be concluded to serve as warning calls amo ng con specifics . These warning calls are desired to drive the intruder out of the territory . T he general function of the response to the playback as one of territoriality may be the reason for the decreases in the maximum frequencies of calls as well as the narrowing of frequency ranges in calls that were observed . All songs seem to converge to a l ower and smaller range of frequencies when an intruder was detected in a territory of H. leucosticta pair . These findings may provide further support for Morton€s 1977 findings that lower frequencies confer larger body size. As lower sounds require more energy to produce, only larger birds can reach certa in lower frequencies Price et al. 2006 . T he observed lowering of frequencies may express a desire of the members of the pair to appear larger to the intruder. Many studies have observed the emission of lower frequencies during a sort of competition between individuals Laidre and Venrencamp 2008, Morton 1977 , Price et al. 200 6 , Ryan and Brenowitz 1985 . In addition to being correlated to large body size, lower frequencies travel farther and with lower interference than higher frequencies Alcock 2005 , Price et al. 2006, Ryan and Brenowitz 1985 . Lower maximum frequency and lower ranges of frequencies may be utilized to communicate over longer distances, ensuring that intruders at varying distances from the pair receive the warning signal. Smaller frequency ranges have also been found to make locat ion of the pairs by predators more difficult Alcock 2005 . These alterations in song characteristics depend on the exact function of the call, whether it is to confuse predators that may be mimicking a con specific call or to increase the likelihood that the warning calls reaches the intruder McGregor 1993 . It is certain though, that there is a trend of change for the calls of H. leucosticta following presence of an intruding con specific, though the sample size of this study was too small to indicate si gnificant changes. The researcher believes that a variety of questions still remain to be answered about the behavioral response of H. leucosticta to con specific playbacks. Future studies could address the time and distance to approach by the pairs to th e location of the playback and how this behavior differs depending on the familiarity of the con specific call used. A similar experiment to the one performed here could be done using con specific songs from pairs at varying distances from the

PAGE 6

Fandel 6 pair€s terri tory. Additional studies should also be completed in response to the dear neighbor theory Hyman 2005 , determining if responses differ between various playbacks used. The function of a s ignal is useful only if this function can be proper ly interpreted by its receiver. As most organisms do not communicate only one piece of information and do not aim to communicate with only one organism, repertoires of communicative devices have developed. Changes in song function should incur changes in s ong structure and characteristics. The results found here indicate that pairs may desire to appear large r o r to send their signals farther by lowering their delta and maximum frequency as a territorial response to con specific intruders. This infers that t he receiver of the signal, whoever that may be, can interpret this change. Results of this study also further show the differentiation of calls of individuals within a species and the overall trend toward a general warning call within the species. AC KNOWLEDGEMENTS I would like to thank Anjali Kumar for her continued efforts to assist me in my research endeavors and her enthusiasm and encouragement . I would also like t o give numerous thanks to Yi men Araya for his many hours teaching me about my birds, for his continual support throughout numerous technological mishaps, and for his extensive knowledge on statistics, without which I would be completely lost. Finally I would like to thank the CIEE Costa Rica, Monteverde program staff for the use of their equipment and trails and for providing me this amazing opportunity to study in a tropical paradise .

PAGE 7

Fandel 7 LITERATURE CITED A LCOCK , J. 2005. Understanding the proximate and ultimate causes of bird song. In Animal Behavior, 8 th Edition, pp. 27 52. Sinuaer Associates, Inc. Sunderland, MA, USA. A SHMOLE , N. P . 1968. Competition and interspecific territoriality in Empidonax Flycatchers. Systematic Zoology 172: 210 212. D INGLE , C. , H A LFWERK , W., AND S LABBEKOORN , H. 2008. Habitat dependent song divergence at subspecies level in the grey breasted wood wren. Journal of Evolutionary Biology 21: 1079 1089. D UNN , K . 2006. Territorial response of Rufous and white Wrens Thryothorus rufalbus to neighbor/stranger conspecific playbacks. In Fall 2006 Tropical Ecology and Conservation, Council on International Educational Exchange Monteverde, Costa Rica, pp.138 143. F ITZPATRICK , J. W., T ERBORGH , J. W., AND W ILLARD , D. E.. 1977. A new species of wood wren from Peru. The Auk 942 195 201. G ARRIGUES , R . 2007. The Birds of Costa Rica . Zona Tropical Publication, Comstock Publishing Associates, New York, pp. 244 245. K ENNEDY , E. D., AND W HITE , D. W. 1996. Interference competition from House Wrens as a factor in the decline of Bewick's Wrens. Conservation Biology 101: 281 284. L AIDRE , M. E. AND V EHRENCAMP , S. L. 2008. Is bird song a reliable signal of aggressive inte nt? Behav. Ecol. Sociobiol 62 : 1207 1211. H YMAN , J. 2005. Seasonal variation in Response to Neighbors and Strangers by a territorial songbird. Ethology 111: 951 961. M ARSHALL B ALL , L., M ANN , N., AND S LATER , J. B.. 2006. Multiple functions to duet singing: hidden conflicts and apparent cooperation. Animal Behaviour 71: 823  831. M C G REGOR , P. K. 1993. Signalling in ter ritorial systems: A context for individual identification, rangi ng and eavesdropping. Biological Sciences 340:237 244. M ORTON , E. S. 1977. On the occurrence and significance of motivation structu r al rules in som e bird and mammal sounds. The American Na turalist 111981: 855 869. M URRAY , B. G. J R . 1971. The Ecological Consequences of interspecific territorial behavior in birds ecology 523: 414 423. O R IANS , G. H., AND W ILLSON , M. F. 1964. Interspecific territories of birds. Ecology45 4: 736 745. P RICE , J. J., E ARNSHAW , S. M., AND W EBSTER , M. S.. 2006. Montezuma oropendolas modify a component of song constrained by body si ze during vocal contests. Animal Behaviour 71:799 807. R YAN , M. J. AND B RENOWITZ , E. A.. 1985. The role of body size, phylog eny, and ambient noise in the evolution of bird song. The American Naturalist 1261: 87 100. S ALAMAN , P., C OOPMANS , P., D ONEGAN , T. M., M ULIGAN , M., C ORTES , A., H ILTY , S. L., AND O RTEGA , L. A. 2003. A new species of wood wren Troglodytidae: Henicorhi na from the western Andes of Colombia . Ornitologia Colombiana 1 : 4 21. S KUTCH , A. E. 1940. Social and sleeping habits of Central Amer ican Wrens. The Auk 573: 293 312.


printinsert_linkshareget_appmore_horiz

Download Options

close

Download PDF

Images

Choose Size
Choose file type



Cite this item close

APA

Cras ut cursus ante, a fringilla nunc. Mauris lorem nunc, cursus sit amet enim ac, vehicula vestibulum mi. Mauris viverra nisl vel enim faucibus porta. Praesent sit amet ornare diam, non finibus nulla.

MLA

Cras efficitur magna et sapien varius, luctus ullamcorper dolor convallis. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Fusce sit amet justo ut erat laoreet congue sed a ante.

CHICAGO

Phasellus ornare in augue eu imperdiet. Donec malesuada sapien ante, at vehicula orci tempor molestie. Proin vitae urna elit. Pellentesque vitae nisi et diam euismod malesuada aliquet non erat.

WIKIPEDIA

Nunc fringilla dolor ut dictum placerat. Proin ac neque rutrum, consectetur ligula id, laoreet ligula. Nulla lorem massa, consectetur vitae consequat in, lobortis at dolor. Nunc sed leo odio.