An evaluation of field and noninvasive genetic methods for estimating Eurasian otter population size

摘要: Successful conservation and management of rare elusive species requires reliable estimates population size, but acquisition such data is often challenging. We compare the two most frequently used methods assessing abundance Eurasian otter (Lutra lutra) populations, noninvasive genetic sampling (NGS) based on genotyping faeces field surveys using snow tracking. In a 100-km2 oligotrophic habitat with linear water bodies, both yielded very similar (10–12 individuals). However, in fishpond area, consisting complex network rivers, fishponds, channels marshes, revealed presence higher number individuals (46–50 genotypes) than survey (38 NGS analysed by capture-mark-recapture (CMR)-based software CAPWIRE provided even estimates, being twice assessed through tracking (76–81 individuals, CI95% = 49–96 55–89). Our results suggest that performance comparable simple habitats, habitats high density combination methods, or CMR analysis data, recommended. emphasise to obtain it necessary follow strict protocols for detection elimination errors. Based literature review our experience, we improvements may increase success rate efficiency otters.