Northern Lesser Black-Backed Gulls: What do They Eat?
Northern Lesser Black-Backed Gulls: What do They Eat?
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北方小黑背鸥：它们吃什么？
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
M. Helberg
中科院分区：
文献类型：
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作者：
J. O. Bustnes;R. Barrett;M. Helberg
抽象的。
较小黑背鸥的指定亚种挪威黑嘴鸥的数量急剧下降，但原因尚不清楚。在挪威北部海岸的两个地区繁殖的这些海鸥的饮食经过了五年(2005-2009年)的评估。在南方地区，58只雏鸡以牛类为主(∼75%ABP[捕食生物量的聚集率]和∼80%的频率；长度70-130 mm)，很可能是青鱼，而0组鲱鱼(40-50 mm长)占∼的20%，并被喂给∼20%的雏鸡。在北部地区(n=23)，略大的0群鲱鱼占猎物质量的60%，并被喂给65%的雏鸟。在这一地区，牛眼蜂和沙丁虫各占猎物∼的17%，分别喂给了20%和30%的雏鸟。其他物种在雏鸟饲料中所占的比例较小。对于成年人，只有反流的颗粒(南部地区有28颗)可用。在2006年和2007年的23个颗粒中，17个(74%)含有海豚(很可能是蛇海豚，Entelurus aequoreus)，而3个含有鲱鱼，2个牛和1个沙丁鱼。在2009年繁殖不佳的季节，成年海鸥还以蓝贻贝、紫贻贝、蟹(短尾蟹)、海胆(棘球总科)和海鸟蛋为食。因此，北方小黑嘴鸥在繁殖过程中可能主要捕食鱼类，而其他猎物可能只有在鱼类不容易获得的情况下才会被利用。此外，鲱鱼对L.F.fuscus的重要性似乎没有之前想象的那么重要。
Abstract.
The Norwegian population of the nominate subspecies of Lesser Black-backed Gull, Larus fuscus fuscus, has declined strongly but the causes are unknown. The diet of these gulls breeding in two regions on coast of northern Norway was assessed over five years (2005–2009). In the southern region, chicks (n = 58) were fed predominantly gadoids (∼75% ABP [aggregated percentage of prey biomass] and ∼80% frequency; 70–130 mm length), probably saithe, Pollachius virens, whereas 0-group herring, Clupea harengus (40–50 mm length) accounted for ∼20% ABP and were fed to ∼20% of the chicks. In the northern region (n = 23), slightly larger 0-group herring comprised ∼60% of the prey mass and were fed to 65% of the chicks. In this area, gadoids and sandeel, Ammodytes spp., each accounted for ∼17% ABP of prey, and were fed to 20% and 30% of the chicks, respectively. Other species made up smaller proportions of chick diets. For adults, only regurgitated pellets (28 in the southern region) were available. Of 23 pellets from 2006 and 2007, 17 (74%) contained pipefish (probably Snake Pipefish, Entelurus aequoreus), whereas three contained herring, two gadoids, and one sandeel. In the poor breeding season of 2009, adult gulls also fed on blue mussels, Mytilus edulis, crabs (Brachyura), sea urchins (Echinoidea) and seabird eggs. Thus, Northern Lesser Black-backed Gulls are probably mainly piscivorous during breeding, and other prey are probably exploited only when fish are not readily available. Further, herring seems to be less important for L. f. fuscus than previously thought.