Evolutionary and Conservation Genetics of the Seychelles Warbler ( Acrocephalus Sechellensis )

Total Page:16

File Type:pdf, Size:1020Kb

Evolutionary and Conservation Genetics of the Seychelles Warbler ( Acrocephalus Sechellensis ) Evolutionary and conservation genetics of the Seychelles warbler ( Acrocephalus sechellensis ) David John Wright A thesis submitted for the degree of Doctor of Philosophy School of Biological Sciences University of East Anglia, UK May 2014 © This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with the author and that use of any information derived there from must be in accordance with current UK Copyright Law. In addition, any quotation or extract must include full attribution. This thesis is dedicated to Laura, my wife and partner-in-crime, for the endless supply of love, support, tea and cake. ii Abstract In this thesis, I investigated how evolutionary forces and conservation action interact to shape neutral and adaptive genetic variation within and among populations. To accomplish this, I studied an island species, the Seychelles warbler (Acrocephalus sechellensis ), with microsatellite markers and major histocompatibility complex (MHC) genes as measures of neutral and adaptive variation respectively. First, I used museum DNA and historical records to reveal a recent bottleneck that provides context for the contemporary genetic variation observed in this species. I then determined the impact of four translocations on genetic diversity over two decades. I found that diversity does not differ significantly between islands but the use of smaller founder sizes in two translocations has caused population divergence. These results indicate that stochastic genetic capture is important in translocations and that future assisted gene flow between populations may be necessary. As a tool for conservation practitioners, I wrote a technical report of the most recent translocation - to Frégate Island - detailing practicalities and outcomes to help inform future translocation policy. Using two translocation events as experiments, I then tested whether MHC-based social mate choice acts to maintain MHC diversity in the Seychelles warbler, finding that male age and heterozygosity, but not MHC, predicted pairing success. Lastly, I investigated survival and reproductive consequences of Ase-ua4 , an MHC class I allele previously shown to confer a survival advantage in the Seychelles warbler. I found widespread patterns of allele frequency increase within cohorts consistent with the survival effect, but no overall increase in population allele frequency over time. I investigated potential antagonistic reproductive mechanisms, but found no clear evidence for why this allele is not driven towards fixation. Collectively, my results provide an interesting case study of the evolutionary conservation approach, whilst providing insight into the importance of maintaining genetic variation in natural populations. iii Acknowledgements I start by giving my sincere thanks to David Richardson for your guidance, friendship and patience through this PhD. Nigel Collar, thank you for the endless positivity and for being my grammar-guru (should that even have a hyphen?!). You two make a great supervisory team! A special thank you to Lewis Spurgin and Karl Phillips – you always had open doors and informative answers to soothe my analytical troubles. I owe my R capabilities to you both. Jenny Gill and John Ewen, thank you for being my examiners. I genuinely enjoyed the viva and appreciated your input. I would also like to thank my funders: the Natural Environment Research Council (NERC) and BirdLife International, for financing my research and I. Cheers! They say a PhD is a lonely business, but that can’t possibly be true when you have ‘team warbler’ with you all the way! Terry Burke and Jan Komdeur, thank you for the biannual injections of fresh ideas and enthusiasm (and for keeping David in order!). Thank you to all Seychelles Warbler Project members past and present; this PhD would simply not have been possible without your collective efforts. Particular thanks to Bebbers, Danni G, Elliemoo, Emma, Fronk, Hannah D, Hannah E, Jildou, Kathryn, Laura, Lewis, Marco, Margarete, Martijn, Michaela, Niki, Owen, Sjouke and Violet. Maybe next time we can think of an easier excuse for tropical adventures…preferably without the dreaded ‘dataface’? Sjouke and Martijn – being trapped on a tiny island with you two is something I’ll never forget…no matter how hard I try! Laura, Hannah – let’s drive the boat ourselves next time! To all at UEA, thanks for putting up with me for these past few years! Particular thanks to Alicia, Aly, Amanda, Amy, Bebbers, Chris, Clare, Claudia, Cock, Conrad, Damian, Danni G, Dave C, Edd, Elizabeth, Elli, Elliemoo, Emma, Helena, Iain, Jacob, Jenny G, Karl, Kitson, Lewis, Liam, Lucy, Martin, Matt, Phil, Sarah, Tim, Will and of course my fellow ‘Cabbages’: Becca, Becky, Cat, Cata, Danni P, Freydís, Jo, José, Kelly, Mikey, Siân, Tom, Vero and Wayne. Thank you all for the helpful discussions, uncontrollable laughter, badminton, volleyball and general distraction. During this PhD, I’ve spent a good deal of time at the NERC facilities at Sheffield University. My time there was always a pleasure (even when the lab work wasn’t!) and I thank all the visiting researchers and staff who made my stays both productive and enjoyable. Particular thanks go to Andy, Gav and Debs for sharing lab woes, tea and friendship. A very special thanks to Maria- Elena, I owe you big time my friend. Thank you to everyone in the Republic of Seychelles that made my fieldwork in paradise something to treasure. Particular thanks to Nature Seychelles and the staff of Cousin Island: April, Aurélien, Dan, Dorothy, Ian, Jessica, Liz, Mary, Nirmal and Riaz and to the proprietors and staff of Aride, Cousine and Frégate – particularly Greg, Kevin, Licia, San-Marie and Tatiana for making it feel like home from home…well ok, maybe home but with a ‘little extra’ sunshine! Mum, Dad, Dan, Ems and the rest of the clan: you are nothing short of inspirational and I thank each of you for your encouragement, love and belief in me. I will repay you for forgetting where the phone was when away, but always seeming to remember where the fridge and pantry were when I came home! Thanks also to my in-laws Andrew, Joy, Ethan, Anna, Paul, Jo, John, Chris and Steve. Thonoir, Paul R, Emma T – thanks for your continued support. Laura, I cannot thank you enough for the endless love, support, encouragement, comfort and cake you have given, and continue to give to me. You made my whole PhD experience that much richer and more enjoyable (and even courageously married me half way through it all!). I’m truly in your debt. Tea, anyone…? iv Contents Page Abstract iii Acknowledgements iv Chapter contributions vi Chapter 1 1 General Introduction Chapter 2 33 Museum DNA reveals the demographic history of the endangered Seychelles warbler Chapter 3 61 The impact of translocation on neutral and functional genetic diversity within and amongst populations of the Seychelles warbler Chapter 4 91 Translocation of the Seychelles warbler to Frégate Island, Seychelles Chapter 5 103 Experimental investigation of MHC-dependent social mate choice in Seychelles warblers Chapter 6 124 Investigating MHC-dependent survival and reproduction in the Seychelles warbler Chapter 7 154 General discussion v Author Contributions At the time of final submission, three of the five data chapters presented in this thesis are published and one is in review. I am lead or joint-lead author on all manuscripts and I have made by far the largest contribution to the work presented in this thesis. Below, I provide a citation for each data chapter, highlight authorship and specify my contributions. Chapter 2: Spurgin LG*, Wright DJ*, Van der Velde M, Collar NJ, Komdeur J, Burke T & Richardson DS (2014) Evolutionary Applications doi: 10.1111/eva.12191. - DJW role in locating and sampling museum specimens, lab work and drafting manuscript (40%). * joint primary authorship Chapter 3: Wright DJ, Spurgin LG, Collar, NJ, Komdeur J, Burke T & Richardson DS (2014) Molecular Ecology 23 , 2165-2177. - DJW role in designing the study, fieldwork and translocation (Frégate), lab work, lead data analyses and drafting manuscript (75%) Chapter 4: Wright DJ, Shah NJ & Richardson DS (2014) Conservation Evidence 11 , 20-24. - DJW role in translocation and drafting manuscript (70%) Chapter 5: Wright DJ, Mannarelli ME, Komdeur J, Burke T & Richardson DS (in review: Behavioral Ecology ) - DJW role in fieldwork, lab work, lead data analyses and drafting manuscript (70%) Chapter 6: Wright DJ, Spurgin LG, Dugdale HL, Komdeur J, Burke T & Richardson DS (in prep.) - DJW role in lab work, lead data analyses and drafting manuscript (65%) vi Chapter 1 General introduction © David Wright Cousin Island, with Praslin Island in the background Chapter 1: General introduction 1.1 Challenges in evolutionary and conservation genetics “…reinforcing the grounds for nature conservation with an evolutionary perspective may help to give conservation a permanence which a utilitarian, and even an ecological grounding, fail to provide in men’s minds.” Otto Frankel, 1974 Evolutionary and conservation genetics are both concerned with the ability of populations to evolve in response to environmental change (Reed & Frankham 2001). A central principle of evolutionary biology is that evolutionary change depends on heritable variation. Consequently, the ability of species to evolve is primarily determined by adaptive, or functional, genetic variation (Frankham 2010). Understanding the amount and persistence of this variation
Recommended publications
  • The Conservation Biology of Tortoises
    The Conservation Biology of Tortoises Edited by Ian R. Swingland and Michael W. Klemens IUCN/SSC Tortoise and Freshwater Turtle Specialist Group and The Durrell Institute of Conservation and Ecology Occasional Papers of the IUCN Species Survival Commission (SSC) No. 5 IUCN—The World Conservation Union IUCN Species Survival Commission Role of the SSC 3. To cooperate with the World Conservation Monitoring Centre (WCMC) The Species Survival Commission (SSC) is IUCN's primary source of the in developing and evaluating a data base on the status of and trade in wild scientific and technical information required for the maintenance of biological flora and fauna, and to provide policy guidance to WCMC. diversity through the conservation of endangered and vulnerable species of 4. To provide advice, information, and expertise to the Secretariat of the fauna and flora, whilst recommending and promoting measures for their con- Convention on International Trade in Endangered Species of Wild Fauna servation, and for the management of other species of conservation concern. and Flora (CITES) and other international agreements affecting conser- Its objective is to mobilize action to prevent the extinction of species, sub- vation of species or biological diversity. species, and discrete populations of fauna and flora, thereby not only maintain- 5. To carry out specific tasks on behalf of the Union, including: ing biological diversity but improving the status of endangered and vulnerable species. • coordination of a programme of activities for the conservation of biological diversity within the framework of the IUCN Conserva- tion Programme. Objectives of the SSC • promotion of the maintenance of biological diversity by monitor- 1.
    [Show full text]
  • Molecular Phylogeny and Phylogeography of Reed Warblers and Allies (Aves: Acrocephalidae)
    Dissertation submitted to the Combined Faculties for the Natural Sciences and for Mathematics of the Ruperto-Carola University of Heidelberg, Germany for the degree of Doctor of Natural Sciences presented by Tayebeh Arbabi Born in Mashhad, Iran Oral examination: 26 June 2014 Molecular Phylogeny and Phylogeography of Reed Warblers and Allies (Aves: Acrocephalidae) Referees: Prof. Dr. Michael Wink Prof. Dr. Marcus Koch i Table of contents Zusammenfassung..................................................................................................................... v Summary .................................................................................................................................. vi Abbreviations ......................................................................................................................... vii Publications ........................................................................................................................... viii 1 Introduction ............................................................................................................................ 1 1.1 General introduction ......................................................................................................... 1 1.1.1 Avian taxonomy ......................................................................................................... 1 1.1.2 Phylogeny and phylogeography ................................................................................. 2 1.1.3 Molecular markers ....................................................................................................
    [Show full text]
  • Insights from a Seychelles Warbler (Acrocephalus Sechellensis) Translocation
    Journal of Ornithology (2018) 159:439–446 https://doi.org/10.1007/s10336-017-1518-8 ORIGINAL ARTICLE The importance of post‑translocation monitoring of habitat use and population growth: insights from a Seychelles Warbler (Acrocephalus sechellensis) translocation Thomas F. Johnson1 · Thomas J. Brown2 · David S. Richardson2,3 · Hannah L. Dugdale1 Received: 20 July 2017 / Revised: 17 September 2017 / Accepted: 2 November 2017 / Published online: 23 November 2017 © The Author(s) 2017. This article is an open access publication Abstract Translocations are a valuable tool within conservation, and when performed successfully can rescue species from extinction. However, to label a translocation a success, extensive post-translocation monitoring is required, ensuring the population is grow- ing at the expected rate. In 2011, a habitat assessment identifed Frégate Island as a suitable island to host a Seychelles Warbler (Acrocephalus sechellensis) population. Later that year, 59 birds were translocated from Cousin Island to Frégate Island. Here, we determine Seychelles Warbler habitat use and population growth on Frégate Island, assessing the status of the translocation and identifying any interventions that may be required. We found that territory quality, an important predictor of fedgling production on Cousin Island, was a poor predictor of bird presence on Frégate Island. Instead, tree diversity, middle-storey vegetation density, and broad-leafed vegetation density all predicted bird presence positively. A habitat suitability map based on these results suggests most of Frégate Island contains either a suitable or a moderately suitable habitat, with patches of unsuitable overgrown coconut planta- tion. To achieve the maximum potential Seychelles Warbler population size on Frégate Island, we recommend habitat regeneration, such that the highly diverse subset of broad-leafed trees and a dense middle storey should be protected and replace the unsuitable coconut.
    [Show full text]
  • Mortimer and Balazs (2000) Post-Nesting Migrations of Hawksbill
    19th Annual SeaTurtle Symposium, 1999 South Padre Island, Texas, USA Foraging Ground Characteristics of Adult Female Hawksbill Turtles Satellite-Tracked from Barbados, West Indies JULIA A. HORROCKS1, LOTUS A. VERMEER2, AND BARRY KREUGER2 1Dept. of Biological and Chemical Sciences, Univ. of the West Indies, St. Michael, Barbados; E-mail [email protected] 2Barbados Sea Turtle Project, Bellairs Research Institute, St. James, Barbados Four adult female hawksbill turtles (Eretmochelys have been resident in the same areas for periods of up to imbricata), fitted with satellite transmitters as part of the four months to date. This paper describes the types of Caribbean Hawksbill Research Tracking Project 1998-99 habitats that the study animals have settled in, their home (NOAA/NMFS), were tracked from their nesting beaches in ranges and patterns of diving behaviour at the different Barbados to their foraging grounds. Following their locations, potential threats to sea turtles in the areas they post-nesting migrations, the study animals traveled to have settled in and the legislative protection for sea turtles foraging ground locations in four different countries and whilst in the foraging grounds. Departure of Marine Turtles from Developmental Habitats: Evidence from Bermuda and Panama ANNE B. MEYLAN1, PETER A. MEYLAN2 AND JENNIFER GRAY-CONKLIN3 1Florida Marine Research Institute, 100 8th Ave. S., St. Petersburg, FL 33701 USA; E-mail [email protected] 2Natural Sciences, Eckerd College, St. Petersburg, FL 33711 USA 3Bermuda Aquarium, Museum and Zoo, Flatts, FLBX, Bermuda Evidence from fieldwork in Bermuda and Panama allows status of individuals that depart from developmental further characterization of the end of the developmental habitats in these two countries.
    [Show full text]
  • Acrocephalidae Species Tree
    Acrocephalidae: Acrocephalid Warblers Madagascan Brush-Warbler, Nesillas typica ?Subdesert Brush-Warbler, Nesillas lantzii ?Anjouan Brush-Warbler, Nesillas longicaudata ?Grand Comoro Brush-Warbler, Nesillas brevicaudata ?Moheli Brush-Warbler, Nesillas mariae ?Aldabra Brush-Warbler, Nesillas aldabrana Thick-billed Warbler, Arundinax aedon Papyrus Yellow Warbler, Calamonastides gracilirostris Booted Warbler, Iduna caligata Sykes’s Warbler, Iduna rama Olivaceous Warbler / Eastern Olivaceous-Warbler, Iduna pallida Isabelline Warbler / Western Olivaceous-Warbler, Iduna opaca African Yellow Warbler, Iduna natalensis Mountain Yellow Warbler, Iduna similis Upcher’s Warbler, Hippolais languida Olive-tree Warbler, Hippolais olivetorum Melodious Warbler, Hippolais polyglotta Icterine Warbler, Hippolais icterina Sedge Warbler, Titiza schoenobaenus Aquatic Warbler, Titiza paludicola Moustached Warbler, Titiza melanopogon ?Speckled Reed-Warbler, Titiza sorghophila Black-browed Reed-Warbler, Titiza bistrigiceps Paddyfield Warbler, Notiocichla agricola Manchurian Reed-Warbler, Notiocichla tangorum Blunt-winged Warbler, Notiocichla concinens Blyth’s Reed-Warbler, Notiocichla dumetorum Large-billed Reed-Warbler, Notiocichla orina Marsh Warbler, Notiocichla palustris African Reed-Warbler, Notiocichla baeticata Mangrove Reed-Warbler, Notiocichla avicenniae Eurasian Reed-Warbler, Notiocichla scirpacea Caspian Reed-Warbler, Notiocichla fusca Basra Reed-Warbler, Acrocephalus griseldis Lesser Swamp-Warbler, Acrocephalus gracilirostris Greater Swamp-Warbler, Acrocephalus
    [Show full text]
  • Family Seychelles: Rain Forests and Reefs of the Indian Ocean March 17—29, 2017
    Family Seychelles: Rain Forests and Reefs of the Indian Ocean March 17—29, 2017 In 1990, 2009, and 2013, Museum Curator Chris Raxworthy and research teams traveled to the Seychelles, where they scoured lush canyons, rocky shores, and steep cliff sides to survey amphibians and reptiles of the Indian Ocean. The information, observations, and genetic samples collected during these expeditions are helping scientists understand the evolutionary history of these organisms and have proven critical to the development of conservation strategies in the region. Embark on your own expedition custom-designed exclusively for Patrons Circle Members by Dr. Raxworthy to highlight the extraordinary biodiversity of the Seychelles’ verdant tropical rain forests and spectacular coral reefs. Activities created by Museum educator Jean Rosenfeld make learning a fun and exciting adventure for the entire family. HIGHLIGHTS EXPLORE the forests of Silhouette Island during the day and at night to search for native wildlife. WONDER at the iconic Coco de Mer, the world’s largest nut of 130-foot-tall palm trees, and hunt for a giant gecko that went missing to science for more than one hundred years. MEET conservation specialists who monitor bird populations on Aride Island, home to the most significant seabird population in the Indian Ocean. SPOT abundant endemic species on Cousin Island, a former coconut plantation that has been reclaimed as a diverse ecosystem, and get close to giant Indian Ocean tortoises. SNORKEL with rare marine life such as hawksbill and green turtles, octopuses, and a kaleidoscope of fish species found on the vibrant reefs of Mahé and Praslin Islands.
    [Show full text]
  • Praslin, Seychelles
    EVERYTHING YOU NEED TO KNOW TO ENJOY YOUR NEXT DREAM DESTINATION! INDIAN OCEAN| PRASLIN, SEYCHELLES PRASLIN BASE ADDRESS Praslin Baie Sainte Anne Praslin 361 GPS POSITION: 4°20.800S 55°45.909E OPENING HOURS: 8:30am – 5pm BASE MAP BASE CONTACTS If you need support while on your charter, contact the base immediately using the contact details in this guide. Please contact your booking agent for all requests prior to your charter. BASE MANAGER Base Manager: Pierre Piveteau Phone: +248 25 27 662 Email: [email protected] CUSTOMER SERVICE PRASLIN Customer Service Manager: Devina Bouchereau Phone: +248 26 44 701 Email: [email protected] BASE FACILITIES ☒ Electricity ☒ Luggage storage ☒ Water ☐ Restaurant ☒ Toilets ☐ Bar ☒ Showers ☒ Supermarket / Grocery store ☒ Laundry ☐ ATM ☐ Swimming pool ☐ Post Office ☐ Wi-Fi BASE INFORMATION LICENSE Sailing license required: ☒ Yes ☐ No PAYMENT The base can accept: ☒ Visa ☒ MasterCard ☐ Amex ☒ Cash EMBARKATION TIME Embarkation is 3pm. YACHT BRIEFING All briefings are conducted on the chartered yacht and will take 40-60 minutes, depending on yacht size and crew experience. The team will give a detailed walk-through of your yacht’s technical equipment, information about safe and accurate navigation, including the yacht’s navigational instruments, as well as mooring, anchorage and itinerary help. The safety briefing introduces the safety equipment and your yacht’s general inventory. STOP OVERS For all DYC charters starting and/or ending in Praslin, the first and last night at the marina is free of charge, including water, electricity and use of shower facilities. DISEMBARKATION TIME Disembarkation is at 9am. The team will inspect your yacht’s equipment and a general visual check of its interior and exterior.
    [Show full text]
  • It's a Bird. It's a Plane. No, It's Both!
    HM Silhouette Cover_Apr2019-Approved.pdf 1 08/03/2019 16:41 Inflight magazine of Air Seychelles • April-June 2020 It’s a bird. It’s a plane. No, it’s both! 9405 EIDC_Silhou_IBC 3/5/20 8:48 AM Page 5 C M Y CM MY CY CMY K Composite [ CEO’S WELCOME ] Dear Guests, Welcome aboard! As you are probably aware, the aviation industry globally is under considerable pressure over the issue of carbon emissions and its impact on climate change. At Air Seychelles we are indeed proud of the contribution we are making towards sustainable development. Following the successful delivery of our second Airbus A320neo aircraft, Pti Merl Dezil in March 2020, I am pleased to announce that Air Seychelles is now operating the youngest jet fleet in the Indian Ocean. Performing to standard, the new engine option aircraft is currently on average generating 20% fuel savings per flight and 50% reduced noise footprint. This amazing performance cannot go unnoticed and we remain committed to further implement ecological measures across our business. Apart from keeping Seychelles connected through air access, Air Seychelles also provides ground handling services to all customer airlines operating at the Seychelles International Airport. Following an upsurge in the number of carriers coming into the Seychelles, in 2019 we surpassed the 1 million passenger threshold handled at the airport, recording an overall growth of 5% increase in arrival and departures. Combining both inbound and outbound travel including the domestic network, Air Seychelles alone contributed a total of 414,088 passengers after having operated 1,983 flights.
    [Show full text]
  • Morphological Variation, Plumage and Song in Pacific Island Acrocephalus Warblers
    202 Notornis, 2018, Vol. 65: 202–222 0029-4470 © The Ornithological Society of New Zealand Inc. From wetlands to islands: morphological variation, plumage and song in Pacific island Acrocephalus warblers BEN D. BELL Centre for Biodiversity & Restoration Ecology, Victoria University of Wellington, Wellington 6140, New Zealand Abstract: Acrocephalus warblers occur across Eurasia, Africa, and Australasia, where they are typically migratory, wetland species, but also occur on islands as sedentary endemics in drier habitats, including forest and scrub. External morphology and song amongst Pacific island Acrocephalus warblers were investigated and comparisons made with Acrocephalus species elsewhere. There was a range of sizes between Pacific island Acrocephalus warblers, many being larger than migratory continental species. Bill:wing length ratios were higher in most Pacific species, and their wings more rounded, than most continental species, but less rounded than swamp-warblers of Africa and adjacent islands. Plumages of W and N Pacific species resembled reed-warblers elsewhere, but in SE Polynesia were more varied, brown or grey dorsally, shaded olive, yellow or rufous, and pale ventrally, shaded white, yellow or buff-white, with a melanistic morph on Tahiti. Spectrographic analysis showed a gradient of song complexity from continental and Marianas/ Micronesia species (A. hiwae, A. syrinx), through to A. taiti and A. vaughani on the Pitcairn islands, which had no song. The mean frequency of Pacific island reed-warbler songs was inversely correlated with mean body size. Bell, B.D. 2018. From wetlands to islands: morphological variation, plumage and song in Pacific island Acrocephalus warblers. Notornis 65(4): 202–222. Key words: Acrocephalus, body-size, evolution, islands, Pacific, reed-warbler, song INTRODUCTION & Cibois 2017).
    [Show full text]
  • Kinship and Familiarity Mitigate Costs of Social Conflict Between
    Kinship and familiarity mitigate costs of social conflict PNAS PLUS between Seychelles warbler neighbors Kat Bebbingtona,b,1, Sjouke A. Kingmab, Eleanor A. Fairfielda, Hannah L. Dugdalec, Jan Komdeurb, Lewis G. Spurgina, and David S. Richardsona,d aSchool of Biological Sciences, University of East Anglia, Norwich NR47TJ, United Kingdom; bBehavioural Ecology and Physiology Group, Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9712CP Groningen, The Netherlands; cSchool of Biology, University of Leeds, Leeds LS29JT, United Kingdom; and dNature Seychelles, Mahé, Republic of Seychelles Edited by Joan E. Strassmann, Washington University in St. Louis, St. Louis, MO, and approved September 6, 2017 (received for review March 15, 2017) Because virtually all organisms compete with others in their social costly (8), so cooperative maintenance of a boundary should be environment, mechanisms that reduce conflict between interacting beneficial, as it reduces the need for costly policing. Kin selection individuals are crucial for the evolution of stable families, groups, could help prevent escalated conflict over territory boundaries, and societies. Here, we tested whether costs of social conflict over but there is also a well-established mechanism by which mutu- territorial space between Seychelles warblers (Acrocephalus sechel- alistic benefits between interacting individuals could resolve lensis) are mitigated by kin-selected (genetic relatedness) or mutu- conflict. The “dear enemy” phenomenon predicts that conflict is alistic (social familiarity) mechanisms. By measuring longitudinal lower between familiar neighbors (9). This is because it is less ’ changes in individuals body mass and telomere length, we demon- costly to maintain territory boundaries with existing neighbors, strated that the fitness costs of territoriality are driven by a complex with whom agreements about territory boundaries have already interplay between relatedness, familiarity, local density, and sex.
    [Show full text]
  • (Eretmochelys Imbricata) on Cousine Island, Seychelles, 1995-1999
    Factors influencing emergences and nesting sites of hawksbill turtles (Eretmochelys imbricata) on Cousine Island, Seychelles, 1995-1999 P.M. Hitchins, O. Bourquin*, S. Hitchins &S.E. Piper** Cousine Island, P.O. Grand Anse, Praslin, SEYCHELLES * P.O. Box 10001, PMB 33, Saipan, MP 96950-8901, USA **Department of Zoology and Entomology, University of Natal, Pietermaritzburg KwaZulu-Natal, SOUTH AFRICA Abstract: Nesting hawksbill turtles were studied on Cousine Island, Seychelles from 1995 – 1999. Emer- gences were highest during November and December, and most (91.0%) took place between October and January when the beaches were most stable and the general wind speeds were at a minimum, with 99.4% emergences occurring during daylight. There was no correlation between emergences and tidal conditions, lunar cycles, daily wind, rainfall, and eroding or depositing beaches. Most nesting took place on or beyond the upper third of beaches. There did not appear to be any special selection for sunlit or shaded conditions, or for vegetation presence or absence. Ultimately choice of a nest site appears to be related to high-tide level and sand moisture level. Key words: Reptilia, Testudines, Cheloniidae, marine turtles, population size Introduction Although the occasional green turtle (Chelonia mydas) is found nesting on the granitic island of Cousine, Seychelles Republic, hawksbill turtles (Eretmochelys imbricata) form the bulk of the breeding population on the island, and any further reference to turtles is of this species. Little previous information has been published on marine turtles on Cousine Island except for an estimate of numbers of hawksbills believed to nest there (Frazier 1984), a brief general description of numbers and breeding (Bourquin & Hitchins 1998).
    [Show full text]
  • Seychelles Warblers: Complexities of the Helping Paradox
    This is a repository copy of Seychelles warblers: complexities of the helping paradox. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/119521/ Version: Publishers draft (with formatting) Book Section: Komdeur, J., Burke, T. orcid.org/0000-0003-3848-1244, Dugdale, H. et al. (1 more author) (2016) Seychelles warblers: complexities of the helping paradox. In: Koenig, W.D. and Dickinson, J.L., (eds.) Cooperative breeding in vertebrates: studies of ecology, evolution, and behavior. Cambridge University Press , Cambridge , pp. 181-196. ISBN 9781107338357 https://doi.org/10.1017/CBO9781107338357.013 © Cambridge University Press 2016. This material has been published in Cooperative breeding in vertebrates: studies of ecology, evolution, and behavior edited by Koenig, W.D. and Dickinson, J.L.. This version is free to view and download for personal use only. Not for re-distribution, re-sale or use in derivative works. Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version - refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher’s website. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request.
    [Show full text]