The Ministry of Ecological Transition launches the most ambitious study to quantify brown bears, in a critical situation and in danger of extinction.

Brown bear in Cantabrian.

The Ministry for the Ecological Transition and the Demographic Challenge (MITECO) and the autonomous communities of Cantabria, Galicia, Asturias and Castilla y León are going to carry out this year the first genetic census of the Cantabrian brown bear population that takes place in Spain.

The study, which will start on September 1 and will last until December 15, it is of vital importance to obtain rigorous data on the species and continue its management using modern scientific criteria, in the same way that it is already developing with several species, including this one, in danger of extinction and in critical situation.

Its objective is to contribute to estimate the existing population of brown bears in the Cantabrian mountain range, as well as scientific knowledge about their kinship and connectivity relationships.

It is also of vital importance, as explained by the Government of Cantabria in a statement, to know the level of inbreeding of the different specimens of the Cantabrian population, taking into account the recent exchange of specimens between the eastern and western subpopulations of the Cantabrian mountain range.

The study will be carried out in a coordinated manner between the different participating entities and simultaneously throughout its distribution area in order to advance in a study of connectivity and kinship of that population.

To do this, the information obtained for genetic individualization using a multi-marker PCR technique that allows analysis of up to 128 variable positions in hair and stool samples.

The field work will be carried out on a sampling surface in the entire Cantabrian mountain range of about 1.5 million hectares, spread over a maximum of 314 5X5 km squares in Castilla y León; 202, in Asturias; 69, in Cantabria, and 43, in Galicia.

The study has the support of the Autonomous University of Barcelona, ​​for genetic individualization through genomic techniques; with the Institute of Evolutionary Biology-CSIC, for studies of connectivity and kinship, and with the Institute of Hunting Resources IREC-CSIC, for methodological advice, data processing and the analysis of the population estimate.

The first phase of the kinship work will take place throughout this year and will continue in 2021 through state-of-the-art sequencing techniques, which will allow to deepen the analysis of genomic heterozygosity (measure of genetic diversity of each individual).