Mating system and reproductive skew in the black rhinoceros

Abstract

Only approximately 2600 black rhinoceros survive today, mainly in small, isolated populations of < 100 animals. The management of remaining black rhinoceros populations aims at preserving natural levels of genetic relatedness and optimizing breeding success, which requires an accurate knowledge of the mating system, reproductive skew and effective population size. DNA was extracted from faecal samples from a community of 35 wild black rhinoceros, and microsatellites were used to characterize patterns of paternity of 19 offspring born from eight females in this community. Paternity could be ascribed unequivocally for each offspring. Although our conclusions must be considered tentative, we present the first genetic evidence that black rhinoceros males are polygynous, with a high variance in reproductive success. We also describe a noninvasive management tool that can be used for the genetic management of this critically endangered species, both in the wild and in captivity.

The lemur syndrome unresolved: extreme male reproductive skew in sifakas (Propithecus verreauxi), a sexually monomorphic primate with female dominance

“…Most studies to date have focused on reproductive skew among females, not only particularly in insects and birds (Reeve and Keller 2001;Haydock and Koenig 2002) but also in mammals (Cooney and Bennett 2000;Clutton-Brock et al 2001;Gerlach and Bartmann 2002;Gilchrist 2006;Young et al 2006). Male reproductive skew, however, has only been studied in a few mammals (Garnier et al 2001;Engh et al 2002;Alberts et al 2003;Widdig et al 2004;Bradley et al 2005), even though reproductive competition is intimately linked to patterns of parental investment, which predispose male mammals towards higher potential reproductive rates, and, hence, competition over access to fertile females (Williams 1966;Trivers 1974;Clutton-Brock and Parker 1992).…”

Remote collection of animal DNA and its applications in conservation management and understanding the population biology of rare and cryptic species

“…Also, analysis of paternity and relatedness based on faecal DNA enabled investigation of reproductive success and mating strategies in a wild translocated population of the endangered black rhinoceros (Dicerous bicornis). The observation of a substantial male reproductive skew (10 of 19 progeny produced over a 10-year period were fathered by a single male) provided evidence for a possible dominance hierarchy and the first genetic proof of polygyny in the species (Garnier et al 2001). Thus, non-invasive sampling can be invaluable in monitoring reproductive patterns in endangered species, thus assisting in the development of reproductive management strategies.…”

“…Fernando et al 2000;Garnier et al 2001;Vigilant et al 2001;Utami et al 2002). This number is likely to increase, as more researchers become aware of the vast potential for molecular analysis in gleaning useful biological data from non-invasive samples.…”

“…Such DNA has successfully been analysed from a variety of animals including primates (Constable et al 1995;Gerloff et al 1999;Utami et al 2002), mountain lions (Ernest et al 2000), coyotes (Kohn et al 1999), bears (Taberlet et al 1997), ungulates (Flagstad et al 1999), dolphins (Parsons et al 1999), bats (Vege and McCracken 2001), common wombats (Banks et al 2002a) and black rhinos (Garnier et al 2001). More unusual sources of DNA have been wolf urine in snow (Valiere and Taberlet 2000), chimpanzee buccal cells from chewed food remnants (wadges) (Sugiyama et al 1993;Takenaka et al 1993;Hashimoto et al 1996;Morin and Woodruff 1996), sloughed skin from cetaceans (Bricker et al 1996;Valsecchi et al 1998) and for birds, nest materials, feathers, eggshells and urine (Morin et al 1994a;Pearce et al 1997;Nota and Takenaka 1999).…”

‘Intentional Genetic Manipulation’ as a conservation threat

“…Small populations on wildlife farms are also subject to the frequent removal of individuals for hunting or breeding. In such populations, a few males may dominate reproduction within a population or several subpopulations via the deliberate use of stud animals (Garnier et al 2001). Such issues are likely to be especially problematic in many southern African wildlife species, regardless of whether they are found on wildlife ranches, since many of these species have historically featured very large populations distributed over vast areas (see Figs.…”