Ad. Fox et C. Mitchell, SPRING HABITAT USE AND FEEDING-BEHAVIOR OF STELLER EIDER POLYSTICTA-STELLERI IN VARANGERFJORD, NORTHERN NORWAY, Ibis, 139(3), 1997, pp. 542-548
The distribution and abundance of Steller's Elder Polysticta stelleri
were studied in Varangerfjord, Norway, in Mag 1995, immediately prior
to the birds' departure for the breeding areas, Almost 80% of the vari
ance in Steller's Elder numbers was explained by a regression model ba
sed upon low tide beach width, suggesting strong selection for gently
shelving coastal profiles, Such habitat is common but restricted in Va
rangerfjord and is rare along surrounding coastlines where the species
is more scarce. The majority of Steller's Elder and the Common Elder
Somateria mollissima were recorded within 200 m of the coast, in contr
ast to the King Elder Somateria spectabilis, which tended to be more t
han 200 m from the shore, More detailed observations at one study site
showed that Common and Steller's Elders fed in different ways and in
separate areas, despite similar proximity to the shore, although the t
wo species did aggregate together to roost at high tide, particularly
during the daytime. Steller's Elder showed a strong tidal rhythm in ac
tivity by day and night, roosting at high tide, diving offshore on the
ebb and flow tides but resorting to algal beds and sandy-mud beaches
to feed at low tide.