Molecular genetic evidence for social group disruption of wild vicunas Vicugna vicugna captured for wool harvest in Chile

Abstract

Since 1994 wild vicunas have been captured and shorn for their wool, yet, there remains a noticeable lack of data regarding the possible influence of capture and shearing upon vicuna biology. Therefore, we assessed post-capture group composition, genetic relatedness, and paternity among animals that were captured for live shearing and release. We captured twenty-six groups (134 animals) on the Chilean Altiplano. Seventy-three percent of Male Groups (designated prior to chase) contained exclusively adult males upon capture,whereas remaining "Male Groups" contained crias and/or adult females and crias. Forty-seven percent of Family Groups (designated prior to chase) contained I adult male, adult females, and the number of crias <= the number of adult females. Remaining Family Groups contained no or multiple adult males, and more crias than adult females. Average relatedness among all vicunas was -0.007. Paternity analysis revealed that 35% of crias were captured with their biological mother and that only 1 cria was captured with both biological parents. Based on previous observations of group composition in the wild, animals from different groups may separate and/or mix during the chasing stage. Improvement of the chasing technique and instituting a post-capture monitoring program may aid in the detection of medium- and long-term impacts regarding group stability, cria survival, and ultimately wool production. (C) 2009 Elsevier B.V. All rights reserved.