Analysis of relatedness and determination of the source of founders in the captive bearded vulture, Gypaetus barbatus, population

Genetic relatedness among founders is a vitalparameter in the management of captivepopulations as kin structure can have asignificant effect on subsequent populationstructure. Methods for inferring relatednessfrom microsatellite markers have all beendeveloped for natural populations; theirapplicability to captive populations withunknown founder origins needs thereforetesting. We used information derived from 14microsatellites in 177 individuals and Quellerand Goodnight's approach, to estimaterelatedness in the captive bearded vulturepopulation and to test the assumption ofunrelated founders. Mean relatedness of knownparent–offspring, full-sib and half-sib pairswithin the captive population were in agreementwith theoretical distributions. Pairwiserelatedness values among the founders had amean of −0.051 (SE ± 0.007) and theirdistribution did only differ marginally fromthe one found in the natural Pyreneanpopulation. A maximum likelihood approach wasused to determine the likelihood of founderpairs to be as closely related as full-sibs orparent–offspring. These results were combinedwith data from 268 bp mitochondrial DNA controlregion sequences and studbook information. Wecould exclude a close relationship among themajority of the 36 successfully reproducingfounders. Our study therefore removesmanagement concerns about hidden problems ofinbreeding and inbreeding depression. Itdemonstrates the applicability of relatednessestimates based on microsatellite allelefrequency data even in captive populations.Furthermore, we verified studbook informationon the origin of two founders from thePyrenees, and show the value of assignmenttests based on microsatellites for deducingfounder origins and their important role infuture monitoring projects.