English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

We report an unusual multispecies foraging assemblage that included larids, shorebirds and passerines which exploited a highly concentrated and ephemeral prey source over a period of three days in July and August 1988. During studies of breeding biology, food-habits and host-parasite ecology among a diverse colonial avifauna at Talan Island in the northern Sea of Okhotsk (59018'N; 149002'E) we observed the formation of mixed-species flocks during extreme high tides of 31 July, 1 August, and 13 August 1988. The first assemblage involved a maximum of 60 birds, including about 45 black-legged kittiwakes (Rissa tridactyla) and 15 slaty-backed gulls (Larus schistisaugus). Feeding activity was intense within 1-3 m of the shore. All birds swam slowly while vigorously dipping and picking minuscule prey items from the surface of the water. The duration of foraging by this flock was not determined. As birds dispersed, we were able to collect numerous pupae and late instar larvae (3-7.3 mm in length) of small dipterans that were washed from the shoreline during the high tide. Detailed observations were made on flocks that assembled in early August. In the first flock, feeding activity extended over 140 min in the late morning to early afternoon of 1 August. This flock was initially composed of adult R. tridactyla feeding along 30 m of cobble beach at a distance of <1 m from shore. As before, there was a gentle surge that washed pupae and larvae from the cobble beach. Whitish larvae and black pupae were visible up to 10-15 m from shore. Within 30 min of initial feeding activity there were 19 adult R. tridactyla, and 12 adult and 3 first year L. schistisaugus. At 75 min there were 52 R. tridactyla and 21 L. schistisaugus vigorously picking larvae and pupae from surface film. Other species of marine birds were not observed. Agonistic interactions between kittiwakes and gulls were not observed. During the peak of foraging activity, feeding intensity by individual birds ranged from 17-31 dips per 30 sec interval (N = 5; 5 = 25). At about 135 min the flock began to disperse, and gulls departed prior to the kittiwakes. The final assemblage lasted for 90 min and was similar to those previously described, being composed of 71 adult R. tridactyla, and 12 adult and a young of the year L. schistisaugus. However, we also observed 3 ruddy turnstones (Arenaria interpres), 10 wood sandpipers (Tringa glareola), 4 common sandpipers (Actitis hypoleucos) and several white wagtails (Motacilla alba) simultaneously feeding among the cobbles in the splash zone adjacent to the larids. All species were feeding on dipteran larvae and pupae. Although all birds were in close proximity, we observed no agonistic interactions.

Larids, Scolopacids, and Passerines Exploiting Ephemeral Prey at Talan Island, Russia