Microsatellite analysis of the natterjack toad (Bufo calamita) in Denmark: populations are islands in a fragmented landscape

摘要: The European natterjack toad (Bufo calamita) has declined rapidly in recent years, primarily due to loss of habitat, and Denmark it is estimated that 50% the isolated populations are lost each decade. To efficiently manage conserve this species its genetic diversity, knowledge structure crucial. Based on nine polymorphic microsatellite loci, gene flow were investigated at 12 sites representing 5–10% localities presently known Denmark. expected heterozygosity (H E) within locality was generally low (range: 0.18–0.43). Further analyses failed significantly correlate diversity with population size, degree isolation increasing northern latitude, indicating a more complex combination factors determining present profile. Genetic differentiation high (overall θ = 0.29) based Bayesian clustering method revealed dataset constituted 11 clusters, defining nearly all sampling as distinct populations. Contemporary among undetectable cases, failure detect pattern by distance major regions supported apparent lack continuum. Indications bottleneck found three suggest remaining Bufo calamita genetically isolated, represent independent units highly fragmented pool. Future conservation management discussed light these results.