ROSSS GULLS IN THE CENTRAL ARCTIC-OCEAN

The central Arctic Ocean is difficult to access. As a result, the bird fauna of the area, with its potential input from all around the circu mpolar perimeter, is still only little ,known. The present paper contr ibutes observations on the distribution of Ross's gull (Rhodostethia r osea) made during the Arctic Ocean 96 expedition from mid-July to mid- September 1996, from the Swedish icebreaker Oden. Ross's gull was the most common bird in the central parts of the Arctic Ocean, with a gran d total of at least 131 individuals seen up to 87 degrees 30'N. Its ab sence further north was judged as due to an early freeze-up. A marked concentration was noted at the shelf-break north of Franz Josef Land i n late July. Most Ross's gulls were observed as single birds or two to gether, but some small flocks were seen, the largest consisting of 10 birds. Most birds were adults, the proportion of immature (second-year ) birds being no more than 10-15%.