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Behavioral Ecology and Sociobiology

, Volume 67, Issue 3, pp 383–393 | Cite as

Alternative strategies in avian scavengers: how subordinate species foil the despotic distribution

  • Corinne J. Kendall
Original Paper

Abstract

Trade-offs in species’ traits can mediate competition and enable coexistence. A key challenge in ecology is understanding the role of species’ trade-offs in maintaining diversity, and evolutionary trade-offs between the abilities of competing species are best understood by considering how competitive advantages change along an environmental gradient. Previous studies of such trade-offs are generally limited to two-species systems and a single trade-off. In this study, I consider the effect of trade-offs in search efficiency and competitive abilities on habitat use patterns among a diverse avian scavenger guild. I hypothesize that species’ dominance status and search efficiency will both be correlated with patch quality. Using counts of searching birds in areas that vary in habitat quality in terms of both wildlife and human settlement density and observations at experimental carcasses, I assess the competitive ability, search efficiency, and habitat use of seven avian scavenger species in Masai Mara National Reserve, Kenya. Findings support the hypothesis with Bateleurs, a species with high search efficiency, and Ruppell’s, Lappet-faced, and White-backed vultures, species with high individual or social dominance, preferentially exploiting habitats of high quality, while Tawny eagles and Hooded vultures, species with low search efficiency and competitive ability, prefer habitats of low quality. This paper demonstrates the importance of considering multiple strategies for assessing the effect of competition on habitat use within complex communities.

Keywords

Interspecific competition Dominance Habitat use Producer–scrounger Vultures 

Notes

Acknowledgments

Research was conducted in collaboration with The Peregrine Fund’s Pan African Raptor Conservation Program. Funding for this study was provided by Princeton University, via the Pompeo M. Maresi Memorial Fund, Hawk Mountain Sanctuary, The Peregrine Fund, and The Explorer’s Club. Advice and comments from Keith Bildstein and my advisor, Daniel Rubenstein, and committee members—Andy Dobson, Henry Horn, Simon Levin, Munir Virani, and David Wilcove—were incredibly helpful as was the statistical support of Charles Yackulic. Field assistance was provided by Wilson and Jon Masek. I would like to thank Narok County Council, the staff of Masai Mara National Reserve, particularly Mr. Minis and Mr. Sindiyo for their assistance and permission to conduct this research as well as the neighboring group ranches and conservancies and Africa Eco-Camps for their support. I’m thankful to Kenya Wildlife Service and the National Museums of Kenya.

Ethical standards

Experiments conducted as part of this study comply with Kenyan laws and were covered under research permit NCST/5/002/R/448.

References

  1. Altmann J (1974) Observational study of behavior: sampling methods. Behaviour 49:227–267PubMedCrossRefGoogle Scholar
  2. Bamford AJ, Monadjem A, Hardy ICW (2009) An effect of vegetation structure on carcass exploitation by vultures in an African savanna. Ostrich 80:135–137CrossRefGoogle Scholar
  3. Barta Z, Giraldeau L-A (1998) The effect of dominance hierarchy on the use of alternative foraging tactics: a phenotype-limited producing-scrounging game. Behav Ecol Sociobiol 42:217–223CrossRefGoogle Scholar
  4. Brown JS, Kotler BP, Mitchell WA (1994) Foraging theory, patch use, and the structure of a Negev desert granivore community. Ecology 75:2286–2300CrossRefGoogle Scholar
  5. Buckley NJ (1996) Food finding and the influence of information, local enhancement, and communal roosting on foraging success of North American vultures. Auk 113:473–488CrossRefGoogle Scholar
  6. Carrete M, Lambertucci SA, Speziale KL, Ceballos O, Travaini A, Delibes M, Hiraldo F, Donazar JA (2010) Winners and losers in human-made habitats: interspecific competition outcomes in two Neotropical vultures. Anim Conserv 13:390–398CrossRefGoogle Scholar
  7. Cortes-Avizanda A, Jovani R, Carrete M, Donazar JA (2012) Resource unpredictability promotes species diversity and coexistence in an avian scavenger guild: a field experiment. Ecology. doi: 10.1890/12-0221.1
  8. Fryxell J, Lundberg P (1997) Individual behavior and community dynamics. Chapman and Hall, New YorkCrossRefGoogle Scholar
  9. Gilbert M, Watson RT, Ahmed S, Asim M, Johnson JA (2007) Vulture restaurants and their role in reducing diclofenac exposure in Asian vultures. Bird Conserv Int 17:63–77CrossRefGoogle Scholar
  10. Hertel F (1994) Diversity in body size and feeding morphology within past and present vulture assemblages. Ecology 75:1074–1084CrossRefGoogle Scholar
  11. Houston DC (1974) Food searching behavior in Griffon vultures. East Afr Wildl J 12:63–77Google Scholar
  12. Houston DC (1976) Breeding of White-backed and Ruppells Griffon Vultures, Gyps africanus and Gyps rueppellii. Ibis 118:14–40CrossRefGoogle Scholar
  13. Houston DC (1989) A change in the breeding season of Ruppell’s Griffon Vultures Gyps rueppellii in the Serengeti in response to changes in ungulate populations. Ibis 132:36–41CrossRefGoogle Scholar
  14. Jackson AL, Ruxton GD, Houston DC (2008) The effect of social facilitation on foraging success in vultures: a modelling study. Biol Lett 4:311–313PubMedCrossRefGoogle Scholar
  15. Kendall C, Virani M (2012) Assessing mortality of African vultures using wing tags and GSM-GPS transmitters. J Raptor Res 46:135–140CrossRefGoogle Scholar
  16. Kirk DA, Houston DC (1995) Social-dominance in migrant and resident turkey vultures at carcasses—evidence for a despotic distribution. Behav Ecol Sociobiol 36:323–332CrossRefGoogle Scholar
  17. Kissui BM (2008) Livestock predation by lions, leopards, spotted hyenas, and their vulnerability to retaliatory killing in the Maasai steppe, Tanzania. Anim Conserv 11:422–432CrossRefGoogle Scholar
  18. Kolowski JM, Holekamp KE (2006) Spatial, temporal, and physical characteristics of livestock depredations by large carnivores along a Kenyan reserve border. Biol Conserv 128:529–541CrossRefGoogle Scholar
  19. Kruuk H (1967) Competition for food between vultures in East Africa. Ardea 55:171–193Google Scholar
  20. Lamprey RH, Reid RS (2004) Expansion of human settlement in Kenya’s Maasai Mara: what future for pastoralism and wildlife? J Biogeogr 31:997–1032CrossRefGoogle Scholar
  21. Lloyd M (1967) Mean crowding. J Anim Ecol 36:1–30CrossRefGoogle Scholar
  22. Margalida A (2008) Bearded vultures (Gypaetus barbatus) prefer fatty bones. Behav Ecol Sociobiol 63:187–193CrossRefGoogle Scholar
  23. Martin GR, Portugal SJ, Murn CP (2012) Visual fields, foraging and collision vulnerability in Gyps vultures. Ibis 154:626–631Google Scholar
  24. Mduma SAR, Sinclair ARE, Hilborn R (1999) Food regulates the Serengeti wildebeest: a 40-year record. J Anim Ecol 68:1101–1122CrossRefGoogle Scholar
  25. Moreno-Opo R, Margalida A, Arredondo A, Guil F, Martin M, Higuero R, Soria C, Guzman J (2010) Factors influencing the presence of the cinereous vulture Aegypius monachus at carcasses: food preferences and implications for the management of supplementary feeding sites. Wildl Biol 16:25–34CrossRefGoogle Scholar
  26. Mundy PJ, Butchart D, Ledger JA, Piper SE (1992) The vultures of Africa. Acorn and Russel Friedman, RandburgGoogle Scholar
  27. Ogutu JO, Piepho HP, Dublin HT, Bhola N, Reid RS (2008) Rainfall influences on ungulate population abundance in the Mara-Serengeti ecosystem. J Anim Ecol 77:814–829PubMedCrossRefGoogle Scholar
  28. Ogutu JO, Piepho HP, Dublin HT, Bhola N, Reid R (2009) Dynamics of Mara-Serengeti ungulates in relation to land use changes. Journal of Zoology 278:1–14CrossRefGoogle Scholar
  29. Otieno PO, Lalah JO, Virani M, Jondiko IO, Schramm K (2010a) Carbofuran and its toxic metabolites provide forensic evidence for Furadan exposure in vultures (Gyps africanus) in Kenya. Bull Environ Contam Toxicol 84:536–544PubMedCrossRefGoogle Scholar
  30. Otieno PO, Lalah JO, Virani M, Jondiko IO, Schramm K-W (2010b) Soil and water contamination with carbofuran residues in agricultural farmlands in Kenya following the application of the technical formulation Furadan. J Environ Sci Heal B 45:137–144Google Scholar
  31. Ottichilo WK, De Leeuw J, Skidmore AK, Prins HHT, Said MY (2000) Population trends of large non-migratory wild herbivores and livestock in the Masai Mara ecosystem, Kenya, between 1977 and 1997. Afr J Ecol 38:202–216CrossRefGoogle Scholar
  32. Ottichilo WK, de Leeuw J, Prins HHT (2001) Population trends of resident wildebeest [Connochaetes taurinus hecki (Neumann)] and factors influencing them in the Masai Mara ecosystem, Kenya. Biol Conserv 97:271–282CrossRefGoogle Scholar
  33. Parker GA, Sutherland WJ (1986) Ideal free distributions when individuals differ in competitive ability—phenotype-limited ideal free models. Anim Behav 34:1222–1242CrossRefGoogle Scholar
  34. Pennycuick CJ (1972) Soaring behavior and performance of some East African birds, observed from a motor-glider. Ibis 114:178–218CrossRefGoogle Scholar
  35. Pennycuick CJ (1983) Effective nest density of Ruppell’s Griffon vulture in the Serengeti-Rift Valley Area of Northern Tanzania. In: Wilbur SR, Jackson AL (eds) Vulture biology and management. University of California Press, Berkeley, pp 172–184Google Scholar
  36. Petrides GA (1959) Competiton for food between five species of East African vultures. Auk 76:104–106CrossRefGoogle Scholar
  37. Ruxton GD, Houston DC (2004) Obligate vertebrate scavengers must be large soaring fliers. J Theor Biol 228:431–436PubMedCrossRefGoogle Scholar
  38. Skagen SK, Knight RL, Orians GH (1991) Human disturbance of an avian scavenging guild. Ecol Appl 1:215–225CrossRefGoogle Scholar
  39. Speziale KL, Lambertucci SA, Olsson O (2008) Disturbance from roads negatively affects Andean condor habitat use. Biol Conserv 141:1765–1772CrossRefGoogle Scholar
  40. Tilman D (1987) The importance of the mechanisms of interspecific competition. Am Nat 129:769–774CrossRefGoogle Scholar
  41. Travaini A, Donazar JA, Rodriguez A, Ceballos O, Funes M, Delibes M, Hiraldo F (1998) Use of European hare (Lepus europaeus) carcasses by an avian scavenging assemblage in Patagonia. J Zool 246:175–181CrossRefGoogle Scholar
  42. Venables WN, Ripley BD (2002) Modern applied statistics with S, 4th edn. Springer, BerlinCrossRefGoogle Scholar
  43. Virani MZ, Kendall C, Njoroge P, Thomsett S (2011) Major declines in the abundance of vultures and other scavenging raptors in and around the Masai Mara ecosystem, Kenya. Biol Conserv 144:746–752CrossRefGoogle Scholar
  44. Virani M, Monadjem A, Thomsett S, Kendall C (2012) Seasonal variation in breeding Rüppell’s Vultures (Gyps rueppellii) at Kwenia, southern Kenya with implications for conservation. Bird Conserv Int 22:260–269CrossRefGoogle Scholar
  45. Wallgren M, Skarpe C, Bergstrom R, Danell K, Granlund L, Bergstrom A (2009) Mammal community structure in relation to disturbance and resource gradients in southern Africa. Afr J Ecol 47:20–31CrossRefGoogle Scholar
  46. Watson RT (2000) Flight, foraging and food of the Bateleur Terathopius ecaudatus: an aerodynamically specialized, opportunistic forager. In: Chancellor RD, Meyburg BU (eds) Raptors at risk. WWGBP/Hancock House, BerlinGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Department of Ecology and Evolutionary BiologyPrinceton UniversityPrincetonUSA
  2. 2.Ornithology Section, Department of ZoologyNational Museums of KenyaNairobiKenya
  3. 3.Department of Ecology, Evolution and Environmental BiologyColumbia UniversityNew YorkUSA

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