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Counts of waterbirds at Western Springs Lake, Auckland, New Zealand | Notornis and Birds New Zealand
[摘要] Waterbirds were counted over ~ 12 ha of Western Springs Lakeside Park, Auckland, twice-monthly from November 2012 to October 2014. On average there were 742 water-birds per count (s.d. = 151.7, range = 511–1081), equating to a mean density of about 62 birds/ha within the study area. The 3 commonest species (mallard, Anas platyrhynchos, black-backed gull, Larus dominicanus and feral goose, Anser anser) made up 63% of all waterbirds counted. Mallard (and all waterbirds combined) were most abundant in summer and autumn. Black-backed gull, Eurasian coot (Fulica atra) and New Zealand scaup (Aythya novaeseelandiae) were seasonally uniform in numbers but red-billed gull (Larus novaehollandiae) were virtually absent from September to December. Spring was the peak season for numbers of black swan (Cygnus atratus), but the seasonal minimum for feral geese. Incidental historical counts trace temporal changes at Western Springs Lake, with a rapid increase of coots in the 1980s and of scaup in the 1990s. Royal spoonbill (Platalea regia) arrived more recently. The counts quantify for the first time the importance of the lake as a habitat for common water-birds on the Auckland isthmus.
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[效力级别]  [学科分类] 动物科学
[关键词] aquatic birds;census;fresh-water lake;gulls;rails;shags;waterfowl [时效性] 
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