Meeting Abstract
The American alligator (Alligator mississippiensis) represents a key species in the coastal Southeast, yet, little is known regarding the mating and nesting dynamics of this species. The Yawkey Wildlife Center (YWC) on the coast of South Carolina represents a unique opportunity to investigate these dynamics. The population of alligators inhabiting the YWC is relatively small, isolated, and has historically remained free of hunting pressures. In addition, long-term capture data characterizing the locations, growth, size, and sex of individuals comprising this population are available. We initially used existing microsatellite markers to examine parentage in 10 nests from 2011. Those markers had been developed and screened for polymorphism from alligators originating in Louisiana. In a sample of 98 adults from YWC the expected and observed heterozygosities were both 0.54 with an average allelic diversity of 5.2. We developed new loci using DNA from a YWC adult and a next generation sequencing approach and identified more than 3000 loci and screened 48 across a subset of YWC adults. Our variation improved with expected and observed heterozyosities increasing to 0.792 and 0.795 respectively. In addition the allelic diversity more than doubled to 11.1. We then screened hatchlings from 38 nests sampled from 2011-2013 and estimated that a minimum of 11% had multiple paternity. The population at YWC may be larger than originally thought given the low number of adults in our genetic database but yet has relatively low genetic diversity. We are expanding the population genetic work to compare multiple barrier island, coastal, and inland populations.
