Population genetics for conservation of spadefoot toads, Pelobates fuscus, in Western and Central Europe

Despite extensive legislation aimed at conservation, European amphibians such as the common spadefoot toad (Pelobates fuscus (Laurenti, 1768)) exhibit alarming declines across large parts of its range. As knowledge about the genetic background of a species has become crucial for species conservation assessment, this study used newly developed microsatellite loci to investigate the genetic diversity and structure of P. fuscus. Clustering revealed major groups that reflect postglacial colonization patterns. Additionally, we found contrasting patterns of genetic diversity across the 66 studied populations, reflecting the conservation status of the species in Europe and with marked genetic impoverishment across most populations in the northwestern part of the species’ distribution. Our findings provide genetic information on the conservation genetic status of the common spadefoot toad across Europe, emphasizing the need for urgent conservation efforts. We recommend further genetic monitorin..., Study area and sampling methods
In this study, we used P. fuscus samples from 66 populations across the species’ range, with 18 of these populations previously analysed as part of an academic qualification (20,21)(Figure 1; Figure S1; Table S1). The majority of DNA samples were collected from adult specimens between 1986 and 2020, primarily through tissue samples from deceased individuals (such as toe clips, liver tissue, or tail clips from tadpoles) and buccal swabs from live adults. In addition, a smaller number of samples were obtained from freshly hatched tadpoles or embryos from clutches. For the latter, the possible introduced bias in allele frequencies by sampling larvae (22) was addressed by removing full siblings from the dataset (see also further below). To account for the fact that data were gathered over a wide geographical range and over a long period of time, we carried out a linear regression analysis (both a full model and one based on AIC) to analyse whether year of sam..., , # Population genetics for conservation of spadefoot toads, *Pelobates fuscus*, in Central Europe

[https://doi.org/10.5061/dryad.gmsbcc2wq](https://doi.org/10.5061/dryad.gmsbcc2wq)

**How was the data retrieved**: In this study we used *P. fuscus* samples from 66 populations across the species’ range, with 18 of these populations previously analysed as part of an academic qualification (20,21)(Figure 1; Figure S1; Table S1). The majority of DNA samples were collected from adult specimens between 1986 and 2020, primarily through tissue samples from deceased individuals (such as toe clips, liver tissue, or tail clips from tadpoles) and buccal swabs from live adults.

DNA was extracted using the DNeasy Tissue Kit (Qiagen) with or without the BioSprint robotic work station with the 96 DNA Plant Kit (Qiagen), according to the manufacturer's protocols. For this study, both newly sampled samples, as well as DNA extract of *Pelobates fuscus* used in previously published and unpublished studies,...,