Artsammansättning och antalsförändringar hos alpina fågelsamhällen under 38 år i de Skandinaviska fjällen

Abstract

The breeding birds of four low alpine plots in Sweden were surveyed at Ammarnäs (65°50'N; two plots, each 100 ha, for 38 and 36 years), Abisko (68°18'; 130 ha, 12 years), and Anjan (63°45'; 150 ha, 11 years). Mean number of species of each plot was between 8 and 12 per year. Mean densities were between 37 and 89 pairs/ km². Anthus pratensis was the most abundant species in all plots (33–52% of all pairs). Pluvialis apricaria had a mean density of between 3 and 4 pairs/km² in all plots, hence a density that may be typical for very large mountain areas. Calcarius lapponicus, endemic to low alpine habitats, varied much between the plots, from 24 pairs/ km² to none. Long-term trends at the Ammarnäs plots included increases of Pluvialis apricaria, Lagopus lagopus and L. mutus, and declines of Anthus pratensis, Eremophila alpestris, Gallinago media and Tringa glareola, but only that of E. alpestris being known to be more than local. The stable bird community accords well with the observed habitat stability.