Oral presentation- Open Session 12th International Mammalogical Congress

Molecular genetics used for analyzing Eurasian beaver dispersal - 20 years after reintroduction in Romania (#383)

Ancuta Fedorca 1 , Georgeta Ionescu 1 , Claudiu Pasca 1 , Alexandru Gridan 1
  1. National Institute for Research and Development in Forestry “Marin Dracea”/Transilvania University, Brasov, Romania

The Eurasian beaver disappeared from Romania in the beginning of the 18th century; recently (1998-2003), 190 individuals from Bavaria (Germany) were reintroduced into 3 main river basins. Nowadays, more than 2500 individuals are occupying habitats across the country on tributaries, with beaver dispersal being realized first over short distances. After the reintroduction, methods used for monitoring species dispersal were presence indices (tree cut, footprint, lodge, dam) and direct observations. Starting in 2015, genetic analyses were used for determining species diversity, dispersal directions and characteristics at the national level. Thus, 62 individuals (genotyped for 11 SSR markers) were captured and biological samples were collected.

Genetic diversity of the species is similar with that in other studies; statistical tests have indicated that beaver individuals are isolated by distance in 5 distance classes (0-50 km, 51-165 km, 166-300 km, 301-360 km and 361-480 km), which can result from the gradual expansion of the reintroduced individuals. Approximately 17 percent of the genetic differences between individuals can be explained by the geographic separation, results confirmed by the appartenance tests. Spatial analysis showed significant and positive autocorrelation within the first 50 km, indicating the presence of related individuals. We identified two directions of the gene flow (west and east); east direction expansion seems to be facilitated by the good quality of the habitats, which are situated along long distances. These results offer a good resolution in determining species evolution, offering an excellent tool for permanent monitoring, determining if the population requires new genetic material from different areas.