Hierarchical dominance structure in reintroduced California condors: correlates, consequences, and dynamics


Populations of reintroduced California condors (Gymnogyps californianus) develop complex social structures and dynamics to maintain stable group cohesion, and birds that do not successfully integrate into group hierarchies have highly impaired survivability. Consequently, improved understanding of condor socioecology is needed to inform conservation management strategies. We report on the dominance structure of free-ranging condors and identify the causes and consequences of rank in condor populations by matching social status with the behavioral and physical correlates of individual birds. We characterized the hierarchical social structure of wild condor populations as mildly linear, despotic, and dynamic. Condor social groups were not egalitarian and dominance hierarchies regulated competitive access to food resources. Absence of kin-based social groups also indicated that condor social structure is individualistic. Agonistic interactions among condors were strongly unidirectional, but the overall linearity and steepness of their hierarchies was low. Although one aggressive male maintained the highest dominance rank across the 3-year observation period, there was considerable fluidity in social status among condors within middle and lower rank orders. Older condors were more dominant than younger birds and younger males supplanted older females over time to achieve higher status. Dominance rank did not predict the amount of time that a bird spent feeding at a carcass or the frequency that a bird was interrupted while feeding. Thus, younger, less dominant birds are able to obtain sufficient nutrition in wild social populations.

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  1. Adams ES (2005) Bayesian analysis of linear dominance hierarchies. Anim Behav 69:1191–1201

  2. Archie EA, Morrison TA, Foley CAH, Moss CJ (2006) Dominance rank relationships among wild female African elephants, Loxodonta africana. Anim Behav 71:117–127

  3. Boyd R, Silk HB (1983) A method for assigning cardinal dominance ranks. Anim Behav 31:45–58

  4. Bradley RA, Terry ME (1952) Rank analysis of incomplete block designs. I. The method of paired comparisons. Biometrika 39:324–345

  5. Bukowinski AT, Bercovitch FB, Alberts AC, Wallace MP, Mace ME, Ancona S (2007) A quantitative assessment of the California condor mentoring program. In: Mee A, Hall LL (eds) California condors in the 21st century. American Ornithologists Union and Nuttall Ornithological Society, Washington DC, pp 197–212

  6. Chancellor RL, Isbell LA (2009) Food site residence time and female competitive relationships in wild gray-cheeked mangabeys (Lophocebus albigena). Behav Ecol Sociobiol 63:1447–1458

  7. Clark M, Wallace MP, David C (2007) Rearing California Condors for release using a modified puppet-rearing technique. In: Mee A, Hall LL (eds) California Condors in the 21st Century. American Ornithologists Union and Nuttall Ornithological Society, Washington, DC, pp 213–226

  8. Coleman JS, Fraser JD (1986) Predation on black and turkey vultures. Wilson Bull 98:600–601

  9. Cox CR, Goldsmith VI, Engelhardt HR (1993) Pair formation in California Condors. Integr Comp Biol 33:126–138

  10. Cristol DA, Nolan V Jr, Ketterson ED (1990) Effect of prior residence on dominance status of dark-eyed juncos, Junco hyemalis. Anim Behav 40:580–586

  11. David HA (1988) The method of paired comparisons. Charles Griffen, London

  12. de Vries HAN (1995) An improved test of linearity in dominance hierarchies containing unknown or tied relationships. Anim Behav 50:1375–1389

  13. de Vries HAN (1998) Finding a dominance order most consistent with a linear hierarchy: a new procedure and review. Anim Behav 55:827–843

  14. de Vries HAN, Stevens JMG, Vervaecke H (2006) Measuring and testing the steepness of dominance hierarchies. Anim Behav 71:585–592

  15. Dewsbury D (1982) Dominance rank, copulatory behavior, and differential reproduction. Q Rev Biol 57:135–159

  16. Drews C (1993) The concept and definition of dominance in animal behavior. Behaviour 125:283–313

  17. Ellis L (1995) Dominance and reproductive success among nonhuman animals: a cross-species comparison. Ethol Sociobiol 16:257–333

  18. Gelman A, Carlin JB, Stern HS, Rubin DB (2004) Bayesian data analysis. Chapman and Hall, Boca Raton

  19. Gelman A, Rubin DB (1992) Inference from iterative simulation using multiple sequences. Stat Sci 7:457–511

  20. Getz WM, Fortmann-Roe S, Cross PC, Lyons AJ, Ryan SJ, Wilmers CC (2007) LoCoH: nonparameteric kernel methods for constructing home ranges and utilization distributions. PLoS One 2:e207

  21. Getz WM, Wilmers CC (2004) A local nearest-neighbor convex-hull construction of home ranges and utilization distributions. Ecography 27:489–505

  22. Gill J (2002) Bayesian methods: a social and behavioral science approach. Chapman and Hall, Boca Raton

  23. Hand JL (1986) Resolution of social conflicts: dominance, egalitarianism, spheres of dominance and game theory. Q Rev Biol 61:201–220

  24. Hewitt SE, Macdonald DW, Dugdale HL (2009) Context-dependent linear dominance hierarchies in social groups of European badgers, Meles meles. Anim Behav 77:161–169

  25. Isbell LA, Young TP (2002) Ecological models of female social relationships in primates: similarities, disparities, and some directions for future clarity. Behaviour 139:177–202

  26. Kaufmann JH (1983) On the definitions and functions of dominance and territoriality. Biol Rev 58:1–20

  27. Kirk DA, Houston DC (1995) Social dominance in migrant and resident turkey vultures at carcasses: evidence for a despotic distribution? Behav Ecol Sociobiol 36:323–332

  28. Koford CB (1953) The California condor. Research Report No. 4. National Audubon Society, Washington, DC, pp 1–154

  29. Komers PE (1989) Dominance relationships between juvenile and adult black-billed magpies. Anim Behav 37:256–265

  30. Lunn DJ, Thomas A, Best N, Spiegelhalter D (2000) WinBUGS—a Bayesian modelling framework: concepts, structure, and extensibility. Stat Comput 10:325–337

  31. Martin P, Bateson P (1993) Measuring behavior, 2nd edn. Cambridge University Press, Cambridge, UK

  32. Mee A, Hall LS (2007) California Condors in the 21st Century. Nuttall Ornithological Club and the American. Ornithologists' Union, Arkansas

  33. Mesterton-Gibbons M, Dugatkin LA (1995) Toward a theory of dominance hierarchies: effects of assessment, group size, and variation in fighting ability. Behav Ecol 6:416–423

  34. Range F, Noe R (2002) Familiarity and dominance relations among female sooty mangabeys in the Taï National Park. Am J Primatol 56:137–153

  35. Romero T, Castellanos MA (2010) Dominance relationships among male hamadryas baboons (Papio hamadryas). J Ethol 28:113–121

  36. Rowell TE (1974) The concept of social dominance. Behav Biol 11:131–154

  37. Smith JE, Powning KS, Dawes SE, Estrada JR, Hopper AL, Piotrowski SL, Holekamp KE (2011) Greetings promote cooperation and reinforce social bonds among spotted hyenas. Anim Behav 81:401–415

  38. Smuts BB, Smuts RW (1993) Male aggression and sexual coercion of females in nonhuman primates and other mammals: evidence and theoretical implications. Adv Stud Behav 22:1–63

  39. Snyder NFR, Snyder HA (1989) Biology and conservation of the California condor. Curr Ornithol 6:174–267

  40. Snyder NFR, Snyder HA (2000) The California condor: a saga of natural history and conservation. Princeton University Press, Princeton

  41. Stahl J, Tolsma PH, Loonen MJJE, Drent RH (2001) Subordinates explore but dominants profit: resource competition in high Arctic barnacle goose flocks. Anim Behav 61:257–264

  42. Sterck EHM, Watts DP, van Schaik CP (1997) The evolution of female social relationships in nonhuman primates. Behav Ecol Sociobiol 41:291–309

  43. Stevens JMG, Vervaecke H, de Vries HAN, van Elsacker L (2007) Sex differences in the steepness of dominance hierarchies in captive bonobo groups. Int J Primatol 28:1417–1430

  44. van Hooff JARAM, Wensing JAB (1987) Dominance and its behavioral measures in a captive wolf pack. In: Frank H (ed) Man and Wolf. Junk W, Dordrecht, pp 219–252

  45. van Schaik CP (1989) The ecology of social relationships amongst female primates. In: Foley VSR (ed) Comparative socioecology: the behavioral ecology of humans and other mammals. Blackwell Scientific, Oxford, pp 195–218

  46. Vehrencamp SL (1983) A model for the evolution of despotic versus egalitarian societies. Anim Behav 31:667–682

  47. Vervaecke H, de Vries HAN, van Elsacker L (2000) Dominance and its behavioral measures in a captive group of bonobos (Pan paniscus). Int J Primatol 21:47–68

  48. Vervaecke H, Stevens JMG, Vandemoortele H (2007) Aggression and dominance in matched groups of subadult Icelandic horses (Equus caballus). J Ethol 25:239–248

  49. Vogel ER (2005) Rank difference in energy intake rates in white-faced capuchin monkeys, Cebus capucinus: the effects of contest competition. Behav Ecol Sociobiol 58:333–444

  50. Wallace MP (2000) Retaining natural behavior in captivity for re-introduction programmes. In: Gosling LM, Sutherland WJ (eds) Behavior and conservation. Cambridge University Press, Cambridge, United Kingdom, pp 300–314

  51. Wallace MP, Temple SA (1987) Competitive interactions within and between species in a guild of avian scavengers. Auk 104:290–295

  52. West-Eberhard MJ (1975) The evolution of social behavior by kin selection. Q Rev Biol 50:1–33

  53. Wittemyer G, Getz WM (2007) Hierarchical dominance structure and social organization in African elephants, Loxodonta africana. Anim Behav 73:671–681

  54. Wittemyer G, Getz WM, Vollrath F, Douglas-Hamilton I (2007) Social dominance, seasonal movements, and spatial segregation in African elephants: a contribution to conservation behavior. Behav Ecol Sociobiol 61:1919–1931

  55. Wrangham RW (1980) An ecological model of female-bonded primate groups. Behaviour 75:262–300

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We wish to acknowledge and thank the following funding agencies, collaborators, staff, assistants, and partner organizations: United States Fish and Wildlife Service (USFWS), Instituto Nacional de Ecologia (INE), Comision Nacional Para El Conocimiento y Uso de la Biodiversidad (CONABIO), Secretaria de Medio Ambiente y Recursos Naturales (SEMARNAT), Centro de Investigacion Cientifica y de Educacion Superior de Ensenada (CICESE), Wildcoast/Costasalvaje, The Los Angeles Zoo, Sempra Energy, Mohammed Saad, Jeff Zuba, Lisa Nordstrom, Kristin Duncan, Alan Lieberman, Katika Bade.

Ethical standards

This research was approved by the San Diego Zoo IACUC animal welfare committee (Project ID#11-014) and the Instituto Nacional de Ecología, México.

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Correspondence to James K. Sheppard.

Additional information

Communicated by C. R. Brown

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Sheppard, J.K., Walenski, M., Wallace, M.P. et al. Hierarchical dominance structure in reintroduced California condors: correlates, consequences, and dynamics. Behav Ecol Sociobiol 67, 1227–1238 (2013) doi:10.1007/s00265-013-1550-5

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  • California condor
  • Socioecology
  • Dominance hierarchy
  • Reintroduction