Genetic pedigree analysis of the pilot breeding program for the rediscovered Galapagos giant tortoise from Floreana island

An aim of many captive breeding programs is to increase population sizes for reintroduction and establishment of self-sustaining wild populations. Genetic analyses play a critical role in these programs: monitoring genetic variation, identifying the origin of individuals, and assigning parentage to track family sizes. Here we use genetic pedigree analyses to examine three seasons of a pilot breeding program for the Floreana island Galapagos giant tortoise, C. niger, that had been declared extinct for ~150 years until individuals with mixed ancestry were recently discovered. We determined that eight of nine founding individuals were assigned parentage to at least one of 130 offspring produced, though there was considerable reproductive skew. In addition, we observed that genetic diversity of the progeny was lower than that of the founders. Despite the observed reproductive skew, we did not see evidence for assortative mating based on relatedness, but there was a trend towards reduced fit...