Iceland gull

The Iceland gull (Larus glaucoides) is a medium-sized gull that breeds in the Arctic regions of Canada and Greenland, but not in Iceland (as its name suggests), where it is only seen during winter. The genus name is from Latin larus, which appears to have referred to a gull or other large seabird. The specific name glaucoides denotes its resemblance to Larus glaucus, a synonym of Larus hyperboreus, the glaucous gull; -oides is Ancient Greek and means "resembling".[2]

Iceland gull
Adult, Ithaca, NY

Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Charadriiformes
Family: Laridae
Genus: Larus
Species:
L. glaucoides
Binomial name
Larus glaucoides
Meyer, 1822
Subspecies
Young Kumlien's gull in New York

It is migratory, wintering from in the North Atlantic as far south as the British Isles and northernmost states of the eastern United States, as well as in the interior of North America as far west as the western Great Lakes. It is much scarcer in Europe than the similar glaucous gull.

The American taxon Kumlien's gull is often considered a subspecies, L. g. kumlieni, of Iceland gull. The taxon Thayer's gull is considered a subspecies, L. g. thayeri, of Iceland gull by the American Ornithological Society as of 2017.[3]

This species breeds colonially or singly on coasts and cliffs, making a nest lined with grass, moss, or seaweed on the ground or cliff. Normally, two or three light brown eggs are laid. They breed in Canada and Greenland, but not in Iceland.

The nominate subspecies, L. g. glaucoides, is very pale in all plumage, with absolutely no melanin in the tips of the primaries in adult plumage. Adults are pale grey above, with a yellowish-green bill. Immatures are very pale grey; the bill is more extensively dark than with glaucous gull, and lacks pink.

The Iceland gull is a medium-sized gull, although relatively slender and light in weight. In length, it can measure from 50 to 64 cm (20 to 25 in), wingspan is from 115 to 150 cm (45 to 59 in), and weight is from 480 to 1,100 g (1.06 to 2.43 lb). Among standard measurements, the wing chord is 37.9 to 44.3 cm (14.9 to 17.4 in), the bill is 3.6 to 5.4 cm (1.4 to 2.1 in), and the tarsus is 4.9 to 6.7 cm (1.9 to 2.6 in).[4][5][6] It is smaller and thinner-billed than the very large glaucous gull, and is usually smaller than the herring gull. It takes four years to reach maturity.

The call is a "laughing" cry like herring gull, but higher pitched.

Like most Larus gulls, these are omnivores, eating fish, molluscs, offal, scraps, and eggs. They forage while flying, picking up food at or just below the water's surface, and they also feed while walking or swimming. Their scavenging habits lead them to frequent garbage dumps, sewage outlets, and places where fish are cleaned.

Eggs, collection Museum Wiesbaden

References
  1. Butchart, S.; Symes, A. (2012). "Larus glaucoides". IUCN Red List of Threatened Species. 2012: e.T22694346A39183818. doi:10.2305/IUCN.UK.2012-1.RLTS.T22694346A39183818.en.
  2. Jobling, James A (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. pp. 174, 219. ISBN 978-1-4081-2501-4.
  3. Chesser, R. Terry; Burns, Kevin J.; Cicero, Carla; Dunn, John L.; Kratter, Andrew W; Lovette, Irby J; Rasmussen, Pamela C.; Remsen, J.V. Jr; Rising, James D.; Stotz, Douglas F.; Winker, Kevin (2017). "Fifty-eighth supplement to the American Ornithological Society's Check-list of North American Birds" (PDF). The Auk. 134 (3): 751–773. doi:10.1642/AUK-17-72.1.
  4. Olsen, Klaus Malling; Larsson, Hans (2004). Gulls of North America, Europe, and Asia. Princeton University Press. ISBN 978-0691119977.
  5. Harrison, Peter (1991). Seabirds: An Identification Guide. Houghton Mifflin Harcourt. ISBN 978-0-395-60291-1.
  6. Dunning, John B., Jr., ed. (1992). CRC Handbook of Avian Body Masses. CRC Press. ISBN 978-0-8493-4258-5.
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