Marking behaviour and census of Eurasian otters ( Lutra lutra ) in riverine habitats: what can scat abundances and non-invasive genetic sampling tell us about otter numbers?

摘要: Growing human-wildlife conflicts and legal conservation obligations increased the need for precise information on Eurasian otter (Lutra lutra) population parameters species status assessment wildlife management measures. Scat surveys have become method of choice to monitor distribution range, abundance habitat use. Although methodological concerns exist, scat is often used as main indicator estimates trends. To evaluate whether counts serve good proxy densities in linear stream habitats, we modelled relationship between old/fresh numbers two spatial scales, including also seasonal effects. Actual marking behaviour were ascertained by genotyping faeces collected at 218 sites along 132.6 km four salmonid streams. Otter our study areas ranged from 0.16 0.28 otters per kilometre. The age scats level scale determining factors when evaluating suitability index densities. Covering large parts an otter’s territory, fresh with density, irrespectively season. On single sites, was not well supported, no could be found using old models. differences site use intensity, traceability accumulation discussed bias numbers.