Olfactory Foraging by Procellariiform Seabirds at South Georgia

许多“管鼻”海鸟（如海燕、信天翁和海鸥）在广阔的、毫无特色的海水中觅食，寻找一种零星分布的食物资源——南极磷虾（南极磷虾）。这些鸟有高度发达的嗅觉系统，对鱼的气味很感兴趣。最近的研究还表明，一些南极物种被二甲基硫化物所吸引，这是一种与高初级生产力相关的气味。有人提出，DMS和其他天然芳香物质构成了海洋上的嗅觉景观，海鸟用它来觅食。这一景观的山峰和山谷为鸟类提供了详细的、即时的信息，告诉它们是否在可能找到食物的地方。尽管对这一景观的一个组成部分（DMS）进行了深入的研究，但对与磷虾更密切相关的其他潜在嗅觉线索的详细研究尚缺乏。例如，目前尚不清楚南极的前体海鸟是否能直接闻到磷虾的气味，但这些信息对于在更大范围内建立嗅觉觅食模型是必要的。这个框架对于探索磷虾分布和密度的变化如何影响海鸟在多年研究中的觅食成功至关重要——这些问题与长期管理有关。本研究的目的是研究南极原胞海鸟对磷虾相关气味的嗅觉反应的物种特异性差异。这项工作将与英国南极调查局（BAS）远洋系外系统核心项目合作进行。这是一项在南乔治亚岛附近进行的多年生态研究，在那里对原伞海鸟进行了密切监测。因此，嗅觉数据将与在南乔治亚附近的伯德岛当地进行的实时饮食抽样联系起来，并将用于协助制定管理和开发该地区海洋资源的战略。

Many procellariiforms or "tube-nosed" seabirds (i.e., the petrels, albatrosses and shearwaters) forage over vast expanses of featureless ocean waters in search of a patchily-distributed food resource, Antarctic krill (Euphausia superba). These birds have highly developed olfactory systems and are attracted to fishy-smelling odors. Recent work has also shown that several Antarctic species are attracted to dimethyl sulfide, an odor associated with high primary productivity. It has been proposed that DMS and other natural aromatics make up an olfactory landscape over the ocean that seabirds use to forage. The peaks and valleys of this landscape provide birds with detailed, instantaneous information about whether they are in areas where they are likely to find food. Although there has been intensive work investigating one component of this landscape (DMS), detailed studies about other potential olfactory cues more closely associated with krill are lacking. It is not known, for example, whether Antarctic procellariiform seabirds can smell krill directly, but this information is necessary to develop models of olfactory foraging on a broader scale.This framework will be critical in exploring how changes in krill distribution and density might affect the foraging success of seabirds over multi-year studies - questions pertinent to long-term management. The objective of this study is to investigate species-specific differences in olfactory responses by Antarctic procellariiform seabirds to krill-related odors. This work will be conducted in collaboration with the British Antarctic Survey (BAS) Peleagic Exosystems Core Program. This is a multi-year ecological study being carried out near South Georgia where procellariiform seabirds have been closely monitored. Olfactory data will thus be linked to real time diet sampling being done locally at Bird Island near South Georgia, and will be used to assist in developing strategies for the management and exploitation of marine resources in the area.