Species Richness of Small Mammals in Finland
- 1 January 1978
- Vol. 31 (2) , 253-256
- https://doi.org/10.2307/3543570
Abstract
The ranges of 21 small mammal spp. occurring in Finland were mapped in a grid of 100 km2. The maximum, 17 spp., was observed in the south, and the minimum, 10 spp., in the north, but the north-south gradient had many exceptions. The most productive region in Finland supported relatively low numbers of species. There was an east-west gradient, with maxima usually being in the east. An island group (.ANG.land) had very low numbers of species. The pattern observed was compared with the species richness maps of vascular plants, Macrolepidoptera and land birds. Isolation by the sea is apparently particularly effective in small mammals. The present species richness of small mammals is probably at equilibrium, and there is a rough balance of range expansions and contractions in the fauna. Isolation operates by reducing rates of range expansion, causing a lower species equilibrium in isolated areas than in areas not separated by isolation barriers.This publication has 0 references indexed in Scilit: