Inbreeding is reduced by female-biased dispersal and mating behavior in Ethiopian wolves

Abstract

Molecular tools have enabled wildlife researchers to obtain accurate information on the kinship, mating behavior, and dispersal of individuals. We genotyped 192 Ethiopian wolves (n ¼ 29 packs) in the Bale Mountains for 17 microsatellite loci to 1) elucidate kinship within and between packs, 2) assess parentage of pups, and 3) evaluate whether inbreeding is avoided by dispersal and/or mating behavior. Mean pairwise relatedness within packs (R ¼ 0.39) was significantly greater than that estimated from random assignment of individuals to packs. However, breeding pairs were most often unrelated, suggesting that female-biased dispersal reduces inbreeding. We assigned maternity to 49 pups and paternity to 47 pups (n ¼ 12 litters) using a combination of exclusion, likelihood analyses (using CERVUS software), and sibship reconstruction. Multiple paternity occurred in 33% of litters; extrapack paternity accounted for 28% of all resolved paternities, occurring in 50% of litters. We found no evidence that extrapack copulations reduce inbreeding; however, more detailed analyses may elucidate the effect of recent population declines and demographic disturbances due to recurring disease outbreaks. The adaptive advantages of female-biased dispersal and the observed mating system are discussed in relation to Ethiopian wolf sociobiology and ecology. Key words: canids, CERVUS, dispersal, EPC, kinship, microsatellites, paternity. [Behav Ecol]