High genetic diversity and demographic history of captive Siamese and Saltwater crocodiles suggest the first step toward the establishment of a breeding and reintroduction program in Thailand

摘要: The Siamese crocodile (Crocodylus siamensis) and Saltwater (C. porosus) are two of the most endangered animals in Thailand. Their numbers have been reduced severely by hunting habitat fragmentation. A reintroduction plan involving captive-bred populations that used commercially is important necessary as a conservation strategy to aid recovery wild populations. Here, genetic diversity population structure 69 individual crocodiles, mostly members captive populations, were analyzed using both mitochondrial D-loop DNA microsatellite markers. overall haplotype was 0.924-0.971 mean expected heterozygosity across 22 loci 0.578-0.701 for species. This agreed with star-like shaped topology network, which suggests high level diversity. ratio number alleles allelic range (M ratio) species considerably lower than threshold 0.68, interpreted indicative historical bottleneck. Microsatellite markers provided evidence introgression three suggest hybridization might occurred between C. siamensis porosus. sequence analysis detected bi-directional male female individuals parent Therefore, identification genetically non-hybrid hybrid long-term management. Relatedness values low within supported their integrity viability breeding management plan. work constitutes first step establishing an appropriate source from scientifically managed perspective situ/ex situ program