其他摘要：Because of logistical constraints little previous information exists on ivory gulls (Pagophila eburnea) in the waters around Svalbard and the east coast of Greenland in late winter/early spring. The Swedish Arctic Ocean 2002 expedition investigated these areas at that time of year and in this paper I report on the observations of ivory gulls made during the expedition. The ivory gull was essentially absent from open waters but was the most common seabird in areas with pack ice, showing behavioural differences depending on local conditions. Generally, the number of ivory gulls was low when there was little plankton in the water. Ivory gulls followed the ship depending on the availability of food items in the wake and also depending on competition from other species, particularly glaucous gulls (Larus hyperboreus). Although ivory gulls were present in most of Fram Strait and the northern part of the East Greenland Current during 6 and 19 May, sightings were few and correlated to the amount of plankton in the water. Aggregations of several hundred were seen on the ice where copulation and other social interaction took place. A previously undescribed pair bonding behaviour during which females seemed to select between two competing males was observed north of Svalbard on 30 April - 1 May. Off Scoresby Sound on 25 May, more than 700 birds were seen migrating north, while farther south along the Greenland coast on 30 May there was little indication of migration although many ivory gulls were seen.
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