Movements and foraging habitats of great shearwaters Puffinus gravis in the Gulf of Maine
Movements and foraging habitats of great shearwaters Puffinus gravis in the Gulf of Maine
复制标题
缅因湾大海鸥的活动和觅食栖息地
DOI：
10.3354/meps12168
复制
发表时间：
2017
影响因子：
2.5
通讯作者：
Robert A. Ronconi
中科院分区：
文献类型：
--
作者：
K. Powers;D. Wiley;A. Allyn;L. Welch;Robert A. Ronconi
：在北大西洋西部，海豚是夏季数量最多的海鸟之一，但人们对它们在这个生态系统中的运动生态和栖息地要求知之甚少。我们在缅因湾捕获的剪切水上部署了平台终端发射器，并使用贝叶斯切换状态−空间模型来描述鸟类的运动、行为、觅食区域、迁徙时间，以及这些栖息地的使用和移动可能与年龄有关。从7月到11月，大剪切流平均每周行进515公里，大部分时间都在墨西哥湾边缘觅食，主要是利用较浅的水域(100米)，那里的水深测量更加陡峭。适用于这些觅食地点数据的广义加性模型揭示了觅食栖息地利用与深度、叶绿素a和海表面温度之间的相关性，但与坡度无关。有趣的是，来自不同标记地点的鸟类之间的这些关系并不一致，这表明了一种基于当地栖息地条件和高流动性的灵活觅食策略。与谢尔瓦特人向南迁徙有关的活动从8月开始，一直持续到9月的大部分时间，鸟类通过加拿大新斯科舍省南部的一条小路离开研究区域。Nape羽毛分析显示，在缅因湾捕获的大多数鸟都是幼鸟；89%的鸟只有3岁大。这些结果表明，使用状态−空间模型对剪切水位置信息进行建模对于识别离散的、高使用率的生境斑块是有用的，作为减少渔业兼捕的努力的一部分。
: In the western North Atlantic, great shearwaters Puffinus gravis are among the most abundant seabirds during summer months, yet little is known about their movement ecology and habitat requirements in this ecosystem. We deployed platform terminal transmitters on shearwaters captured in the Gulf of Maine and used a Bayesian switching state−space model to describe bird movements, behavior, foraging areas, migration timing, and how such habitat use and movements might be related to age. From July to November, great shearwaters traveled an average of 515 km per week and spent most of their time foraging around the rim of the gulf, primarily using shallower waters (<100 m), where bathymetry was more steeply sloped. A generalized additive model fit to these foraging locations data revealed correlations between foraging habitat use and depth, chlorophyll a and sea surface temperature, but not slope. Interestingly, these relationships were not consistent across birds from different tagging sites, suggesting a flexible foraging strategy based on local habitat conditions and high mobility. Movements associated with the shearwa-ters’ southern migration began in August and continued through much of September, with birds leaving the study area via a pathway south of Nova Scotia, Canada. Nape plumage analysis showed most of the captured birds in the Gulf of Maine were young birds; 89% were <3 yr old. These results suggest that modeling shearwater location information using state− space models can be useful in identifying discrete, high-use habitat patches as part of efforts to reduce fishery bycatch.