| 词条 | White-winged scoter |
| 释义 |
| name = White-winged scoter | image = White-winged Scoter.jpg | image_caption = Adult male of the American race deglandi | image2 = Melanitta fusca var deglandi f Toronto.jpg | image2_caption = Female, Toronto | status = LC | status_system = IUCN3.1 | status_ref = [1] | genus = Melanitta | parent = Melanitta (Melanitta) | species = deglandi | authority = (Bonaparte, 1850) | synonyms = Melanitta fusca deglandi Melanitta fusca stejnegeri | subdivision_ranks = Subspecies | subdivision =
| range_map = Melanitta deglandi map.svg }} The white-winged scoter (Melanitta deglandi) is a large sea duck. The genus name is derived from Ancient Greek melas "black" and netta "duck". The species name commemorates French ornithologist Côme Damien Degland.[2] DescriptionThe white-winged scoter is one of three North American scoter species and the largest species of scoter. It is characterised by its bulky shape and large bill. Females range from {{convert|950|-|1950|g|lb|abbr=on}} and {{convert|48|–|56|cm|in|abbr=on}}, averaging {{convert|1180|g|lb|abbr=on}} and {{convert|52.3|cm|in|abbr=on}}. She is brown with pale head patches. The male ranges from {{convert|1360|-|2128|g|lb|abbr=on}} and from {{convert|53|–|60|cm|in|abbr=on}}, averaging {{convert|1380|g|lb|abbr=on}} and {{convert|55|cm|in|abbr=on}}. He is all black, except for white around the eye and a white speculum. This scoter's bill has a black base and a large knob. There are a number of differing characteristics of the Eastern Siberian race and the American race from Alaska and Canada to west of the Hudson Bay. Males of the American subspecies have browner flanks, dark yellow coloration of most of the bill and a less tall bill knob, approaching the velvet scoter. The Asian form has a very tall knob at the base of its mostly orange-yellow bill. Females are identical in the field. The Latin binomial commemorates the French zoologist Dr. Côme-Damien Degland (1787–1856). TaxonomyIt was formerly considered to be conspecific with the velvet scoter, and some taxonomists still regard it as so. These two species, and the surf scoter, are placed in the subgenus Melanitta, distinct from the subgenus Oidemia, black and common scoters. The subspecies stejnegeri has been suggested to be a full species, according to a new study.[3] DistributionThe white-winged scoter breeds over the far north of Asia east of the Yenisey Basin, and North America. It winters further south in temperate zones, on the Great Lakes, the coasts of the northern United States and the southern coasts of Canada, and Asia as far south as China. It forms large flocks on suitable coastal waters. These are tightly packed, and the birds tend to take off together. It has occurred as a vagrant in Europe, including Scotland,[4] Iceland,[5] Norway and Ireland,[6] BehaviorBreedingThe lined nest is built on the ground close to the sea, lakes or rivers, in woodland or tundra. 5–11 eggs are laid. The pinkish eggs average {{convert|46.9|mm|in|abbr=on}} in breadth, {{convert|68.2|mm|in|abbr=on}} in length and {{convert|82.4|g|oz|abbr=on}} in weight. The incubation period can range from 25 to 30 days. After about 21 days, neighboring females may start to behave aggressively towards other nesting females, resulting in confusion and mixing of broods. By the time she is done brooding, a female may be tending to as much as 40 offspring due to the mixing from these conflicts. The female will tend to her brood for up to 3 weeks and then abandon them, but the young will usually stay together from another 3 weeks. Flight capacity is thought to be gained at 63 to 77 days of age. FoodIn freshwater, this species primarily feeds on crustaceans and insects; while in saltwater areas, it feeds on molluscs and crustaceans. The favorite foods of the American (sub)species are an amphipod (Hyalella azteca) in freshwater, and rock clams (Protothaca staminea), Atlantic razor clams (Siliqua spp.), and Arctic wedge clams (Mesodesma arctatus). References1. ^{{cite iucn | author = BirdLife International | year = 2018 | title = Melanitta deglandi | journal = The IUCN Red List of Threatened Species | volume = 2018 | page = e.T22734194A132663794 | url = https://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T22734194A132663794.en | accessdate = 23 December 2018}} 2. ^{{cite book | last= Jobling | first= James A | year= 2010| title= The Helm Dictionary of Scientific Bird Names | publisher = Christopher Helm | location = London | isbn = 978-1-4081-2501-4 |pages =132, 246}} 3. ^{{cite web|url=http://www.hbw.com/species/siberian-scoter-melanitta-stejnegeri|title=Siberian Scoter (Melanitta stejnegeri)|publisher=}} 4. ^{{cite web | url = https://www.bou.org.uk/british-list/recent-announcements/changes/ | title = Changes to the British List | date = 5 December 2013 | accessdate = 23 December 2018 | publisher = British Ornithologists' Union}} 5. ^{{cite web | url = https://notendur.hi.is/yannk/status_meldeg.html | title = American White-winged Scoters in Iceland | accessdate = 23 December 2018 | work = The Icelandic Birding Pages | publisher = Gunnlaugur Pétursson / Yann Kolbeinsson }} 6. ^{{cite web | author = Martin Garner | year = 2014 | title = Velvet, White-winged and Stejneger's Scoters: A Photographic Guide | url = https://www.birdguides-cdn.com/cdn/LegacyBirdwatchArticles/velvet%20and%20white-winged%20scoters%20id%20photo%20guide_birdwatchfeb14lr.pdf | accessdate = 23 December 2018 | publisher = Birdwatch}} External links{{Commons category|Melanitta deglandi}}{{Wikispecies|Melanitta deglandi}}
4 : Melanitta|Native birds of Alaska|Birds of Canada|Birds described in 1850 |
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