Silver gull

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Silver gull
Silver gull jan 09.jpg
Adult
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Charadriiformes
Family: Laridae
Genus: Chroicocephalus
Species: C. novaehollandiae
Binomial name
Chroicocephalus novaehollandiae
(Stephens, 1826)
Subspecies

C. n. forsteri (Mathews, 1912)
C. n. gunni Mathews 1912
C. n. novaehollandiae (Stephens, 1826)

Synonyms

Larus novaehollandiae

The silver gull (Chroicocephalus novaehollandiae) also known simply as "seagull" in Australia, is the most common gull seen in Australia. It has been found throughout the continent, but particularly at or near coastal areas.

The silver gull should not be confused with the herring gull, which is called "silver gull" in many other languages (scientific name Larus argentatus, German Silbermöwe, French Goéland argenté, Dutch zilvermeeuw) but is a much larger, robust gull with no overlap in range.

Taxonomy[edit]

The South African Hartlaub's gull (C. hartlaubii) and the New Zealand red-billed gull (C. scopulinus) were formerly sometimes considered to be subspecies of the silver gull. As is the case with many gulls, it has traditionally been placed in the genus Larus but is now placed in the genus Chroicocephalus.

Description[edit]

Juvenile (first winter)

The head, body and tail are white. The wings are light grey with white spotted, black tips.[2] Adults range from 40–45 cm in length.[2] Mean wing span is 94 cm.[3] Juveniles have brown patterns on their wings, and a dark beak. Adults have bright red beaks—the brighter the red, the older the bird.

Distribution and habitat[edit]

Silver gulls are found in all states of Australia.[3] It is a common species, having adapted well to urban environments and thriving around shopping centres and garbage dumps.

Silver gulls have twice been recorded in the United States; one bird was shot in August 1947 at the mouth of the Genesee River, Lake Ontario and another was photographed in Salem County, New Jersey, in autumn 1996. Both are nowadays believed to have escaped from captivity (AOU, 2000).

Behaviour[edit]

Egg and nestlings in nest at Phillip Island Nature Park, Victoria

The silver gull has a sharp voice consisting of a variety of calls. The most common call is a harsh 'kwee-aarr'.[2]

Feeding[edit]

The silver gull naturally feeds on worms, fish, insects and crustaceans. It is a successful scavenger, allowing increased numbers near human settlements.

Breeding[edit]

Breeding occurs from August to December.[3] The nest is located on the ground and consists of seaweed, roots and plant stems.[3] The nests may be found in low shrubs, rocks and jetties.[3] Typical clutch size is 1–3 eggs.[2][3]

Various views and plumages[edit]

References[edit]

  1. ^ BirdLife International (2012). "Larus novaehollandiae". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013. 
  2. ^ a b c d "Silver Gull". Birds in Backyards, Australian Museum. 2007-01-23. Archived from the original on 2010-04-13. Retrieved 2009-05-10. 
  3. ^ a b c d e f Pizzey, Graham; Knight, Frank (1997). Field Guide to the Birds of Australia. Sydney, Australia: HarperCollinsPublishers. p. 111. ISBN 0-207-18013-X. 
  • American Ornithologists' Union (AOU) (2000): Forty-second supplement to the American Ornithologists' Union Check-list of North American Birds. Auk 117(3): 847–858. DOI: 10.1642/0004-8038(2000)117[0847:FSSTTA]2.0.CO;2
  • Pons J.M., Hassanin, A., and Crochet P.A.(2005). Phylogenetic relationships within the Laridae (Charadriiformes: Aves) inferred from mitochondrial markers. Molecular phylogenetics and evolution 37(3):686-699