Habitat use by wintering Steller’s Eiders Polysticta stelleri in northern Norway.

Habitat use of Steller’s Eiders Polysticta stelleri was studied in Varangerfjord, northern Norway, during three winter periods (November, January and April) in 1996/97. We partitioned habitats based on water depth and benthic conditions, and compared the benthic characteristics in known feeding areas to nearby areas avoided by Steller’s Eiders. On average 88% of the birds were in natural habitats, outside of harbours. Mean water depth at feeding areas varied from 3.7 m in November to 2.5 m in April. Overall 89% of eiders foraged by diving at locations where water depths were less than 5 m. Steller’s Eiders foraged in areas with underwater vegetation, predominantly in kelp beds. Two factors were positively associated (P < 0.05) with the probability that an area was used by Steller's Eiders: the proportion of the area covered by the kelp species Laminaria hyperborea and the vegetation density. Shallowly flooded kelp beds are the prime habitat for Steller's Eiders in Varangerfjord, and protection of these habitats is probably of great importance for preserving the species in the area

Bustnes J.O. & Systad G.H, ARDEA 89 (2): 267-274