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Population status of the New Zealand king shag (Leucocarbo carunculatus) | Notornis and Birds New Zealand
[摘要] Between 1992 and 2002, the 4 main colonies of the king shag (Leucocarbo carunculatus) in the outer Marlborough Sounds, New Zealand were surveyed 10 times. Additional information was gathered at 2 smaller colonies off D’Urville Island. The average total population was estimated to be 645 birds, with 92% at Duffers Reef, Trio Islands, Sentinel Rock, and White Rocks, including 102-126 breeding pairs, with an annual recruitment of 40-68 birds. Surveys before 1992 may have included only c. 40% of the population, because most counts seem to have been done during the middle of the day when significant numbers of shags were absent feeding. If historic counts at colonies are adjusted for birds absent feeding, numbers appear to have been stable for at least the past 50 years — and possibly over 100 years — which would suggest a long-term balance between recruitment and mortality.
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[效力级别]  [学科分类] 动物科学
[关键词] Leucocarbo carunculatus;New Zealand King Shag;population size;population trend [时效性] 
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