Molecular methods can play a crucial role in species management and conservation. Despite the usefulness of genetic approaches, they are often not explicitly included as part of species recovery plans and conservation practises. The Natterjack toad (Epidalea calamita) is regionally Red-Listed as Endangered in Ireland. The species is declining and is now present at just seven sites within a highly restricted range. This study used 13 highly polymorphic microsatellite markers to analyse the population genetic diversity and structure. Genetic diversity was high with expected heterozygosity between 0.55 and 0.61 and allelic richness between 4.77 and 5.92. Effective population sizes were small (Ne < 100 individuals), but not abnormal for pond breeding amphibians. However, there was no evidence of historical or contemporary genetic bottlenecks or high levels of inbreeding. We identified a positive relationship between Ne and breeding pond surface area, suggesting that environmental factors are a key determinant of population size. Significant genetic structuring was detected throughout the species’ range, and we identified four genetic entities that should be considered in the species’ conservation strategies. Management should focus on preventing further population declines and future loss of genetic diversity overall and within genetic entities while maintaining adequate local effective population size through site-specific protection, human-mediated translocations and head-start programs. The apparent high levels of genetic variation give hope for the conservation of Ireland’s rarest amphibian if appropriately protected and managed.
Bibliographical noteFunding Information:
This study was supported by National Parks and Wildlife Service (NPWS), Department of Culture, Heritage and the Gaeltacht, Republic of Ireland.
This study was commissioned and funded by the National Parks and Wildlife Service (NPWS), Department of Culture, Heritage and the Gaeltacht as a component part of a larger study won under open competitive tender by Queen’s University Belfast (QUB). Thanks to all those volunteers and work placement students who participated in Natterjack monitoring surveys. We are grateful to landowners for providing access to their land.
© 2021, The Author(s).
- Conservation genetics
- Effective population size
- Epidalea calamita
- Microsatellite DNA
- Population structure
- Species conservation
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics