Can small, isolated primate populations be effectively reinforced through the release of individuals from a captive population?

Sex Ratio at Birth and Age-Reversed Dominance among Female Varecia

“…The benefit to the daughter is clear in that she inherits an established, familiar territory. Although there are possibilities of inbreeding in that the daughter's father may still be resident, Varecia shows male transfer and male visiting during the breeding season in both the wild and captivity [Morland, 1991;White et al, 1993;Britt et al, 2003] so that unrelated breeding males should also be present. It is more difficult to understand why the high-ranking mother should voluntarily give up a proven breeding situation.…”

“…The ruffed lemur, V. variegata , is a large (3-5 kg), diurnal prosimian primate that exhibits wide variation in social organization, in both captivity and the wild, ranging from small pair-bonded groups to multi-male multi-female groups [Petter et al, 1977;Tattersall, 1982;Foerg, 1982b;Pereira et al, 1988;Morland, 1990Morland, , 1991Morland, , 1993aWhite et al, 1992White et al, , 1993Balko, 1998;Ratsimbazafy, 2002;Britt et al, 2003;Erhart and Overdorff, 2007;Vasey, 2007]. Varecia are female dominant with daughters disputing the top rank and outranking their mothers as they approach puberty [Foerg, 1982b;White, 1991;White et al, 1993].…”

“…Male transfer has been documented for captive groups and indicated in wild Varecia groups [Morland, 1991;White et al, 1993;Britt et al, 2003]. Relationships between daughters and mothers are highly variable.…”

Predation and Cathemerality

“…This review of the literature makes clear that the largest living carnivore on Madagascar, the fossa ( Cryptoprocta ferox , Viverridae), is cathemeral [Kohncke and Leonhardt, 1986;Dollar et al, 1997], is a major cause of mortality in many lemur species and is widely regarded as a lemur-hunting specialist [Wilson et al, 1989;Goodman et al, 1993;Rasoloarison et al, 1995;Wright, 1995Wright, , 1998Wright et al, 1997;Hart, 2000;Britt et al, 2001Britt et al, , 2003Goodman, 2003;Hawkins, 2003]. Table 2 lists the lemuriform species that have been reported to be preyed upon by C. ferox , and the activity patterns of those lemur species.…”

“…Slobodkin, , 1974. Since the report by Wright et al [1997], patterns of fossa predation of ruffed lemurs (V. v. variegata) reintroduced to Betampona Reserve in northeastern Madagascar [Britt et al, 2001[Britt et al, , 2003] provide clear evidence of episodic predation; Britt et al suggested that one fossa was responsible for the deaths. Recently, a similar episodic bout of predation on diademed sifakas (P. d. diadema) , apparently by one fossa, occurred in a forest fragment at Tsinjoarivo in eastern Madagascar [Irwin, pers.…”