Dear otter friends!

Finally I have finished my thesis entitled:

Ecology of the otter (Lutra lutra) in central Finland and methods for estimating the densities of populations.

The thesis includes: S-shaped increasing of the population, density-dependent cub production, Source-sink habitat structure in otter populations, and of course, different snow-tracking methods.

Abstract:

In this long-term study, the ecology of otters was studied extensively in central Finland. The diet of otters was studied by analysing spraints (faeces). The activity of otters was investigated by following sprainting activity in summer and by snow-tracking in winter. Snow-tracking was also used to study the home ranges, breeding and density of otters. To estimate population densities two new snow-tracking methods were developed. The home range mapping method (HMM) is very intensive, but gives an exact estimate of the number of otters. The one-visit census (OVC) is a sampling method that provides a faster way to estimate the population densities.

A summary of all included publications, with also some more ecological information for local otter population is available in:

http://joypub.joensuu.fi/publications/dissertations/sulkava_ecology/index_en.html

Dr Risto Sulkava

University of Joensuu
Department of Biology
Finland