Rosss Gull (Rhodostethia rosea)

Rosss Gull

[order] CHARADRIIFORMES | [family] Laridae | [latin] Rhodostethia rosea | [UK] Rosss Gull | [FR] Mouette rosee | [DE] Rosenmowe | [ES] | [NL] Ross’ Meeuw

Subspecies

Genus Species subspecies Breeding Range Breeding Range 2 Non Breeding Range
Leucophaeus rosea
Rhodostethia rosea EU, NA n coasts Arctic Ocean

Physical charateristics

A small gull, with a tiny, dark bill, pale gray upperparts, and underparts washed with pink in adults. In flight, the long, wedge-shaped tail and prominent white trailing edge of the wing are evident; the underwing usually appears darker than the upperwing.
In alternate plumage, the pinkish cast to the plumage and black ring around the head are diagnostic. In basic plumage, note the evenly gray wings on both the upper and under surfaces and the wedge-shaped tail. In first-winter plumage the wedge-shaped tail is diagostic as is the small bill.

Listen to the sound of Rosss Gull

[audio:http://www.aviflevoland.nl/sounddb/R/Rosss Gull.mp3]

Copyright remark: Most sounds derived from xeno-canto

wingspan min.: 90 cm wingspan max.: 100 cm
size min.: 29 cm size max.: 31 cm
incubation min.: 0 days incubation max.: 0 days
fledging min.: 0 days fledging max.: 0 days
broods: 0   eggs min.: 0  
      eggs max.: 0  

Range

Eurasia, North America : North coasts

Habitat

Breeding mainly on borderline between low Arctic and subarctic, extending even into boreal taiga zone in northern Siberia. Melting snow on tundra underlain by permafrost creates a muddy boggy terrain interspersed with countless shallow pools, which are dotted with sedge and moss, and with small low islets, partly within zone of thickets of grey alder and willows, but partly on open tundra, lying some way in from principal river channels. Nests placed on wet spots near water, in association with Arctic Tern, Spotted Redshank, Ruff, and other not exclusively arctic species.

Reproduction

Breeding sites discovered in Siberia were surrounded by vegetation that included bushes and hardwood trees and occasionally
coniferous trees and resembled the habitat near the Canadian mainland breeding site of Churchill, Manitoba. The habitat on Prince Charles Island is more truly arctic and probably more closely resembles the other breeding localities found in the High Arctic, elsewhere referred to as marshy wetlands in subalpine and boreal tracts. Pairs of Ross’s gulls arrive
together at breeding sites. Hence, paired Ross’s gulls may remain together during the non-breeding season, or pair bonds could also be established on the winter quarters. Ross’s Gulls nest is in loose colonies, on low islets or marshes near extensive open water in early spring. It may be a well-formed scrape or a barely perceptible depression in gravel or moss or other vegetation, often only a few inches above the water. One to three eggs are laid and incubated by both parents.

Feeding habits

Their diet mostly consists of marine crustacea, other plankton animals and small fish. Inland, during nesting season, they become mostly insectivorous.

Conservation

This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend is not known, but the population is not believed to be decreasing sufficiently rapidly to approach the thresholds under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Rosss Gull status Least Concern

Migration

Migratory. Main wintering areas northern Bering Sea and Sea of Okhotsk; some birds move south as far as Kuril islands. Most high-latitude marine records north of Europe date from early period of polar exploration by ship, and therefore relate to late summer and autumn only. Breeding grounds in north-east Siberia reoccupied late May to early June, according to time of thaw; mass departures occur in second half of July.

Distribution map

Rosss Gull distribution range map

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