Conservation Genetics and Non-Invasive Genetic Sampling of Eurasian Otters (Lutra lutra) in the Czech and Slovak Republics

Many important basic parameters for successful conservation management of Eurasian otter (Lutra lutra) populations are still not fully understood. Otters are rare and elusive animals, and it is very difficult to study their abundance and population structure. Over the past years, however, genetic methods have provided a new approach to this problem. If non-invasively obtained samples, such as faeces, are analysed, disturbing or even observing the animals is not required. We used a non-invasive genetic method to assess population size, sex ratio and spatial distribution of otters in two different habitats. Further, we studied the genetic structure of otters in the Czech and Slovak Republics using DNA extracted from both tissue and spraint samples. A total of 448 spraint samples and 134 tissues were analysed using 10 microsatellite loci and a SRY marker. At the first study site, a mountainous area of Slovensky raj National Park, 13 individuals (7 males and 6 females) were identified, while at the second site, a fishpond area of T eboňsko Biosphere Reserve, it was 50 individuals (29 males and 21 females) for the same area size (100 km2). When studying genetic structure of otter populations in the Czech and Slovak Republics, a relatively high level of genetic differentiation was found between the Czech and Slovak populations (FST = 0.154), supported by a perfect assignment in Bayesian clustering. Both MSVAR and BOTTLENECK programmes, which infer demographic history, indicated the occurrence of recent population bottleneck in both populations. Despite recent recovery, otter populations in both countries are still vulnerable.