Foraging and movement ecology of two sympatrically breeding Antarctic storm-petrels

风暴海燕是世界上数量最多的远洋海鸟之一，是海洋生态系统的重要组成部分。然而，由于它们体型小，生活在远洋，它们的营养生态很难研究，特别是在非繁殖期，它们在开阔的海洋上度过。对黑腹风暴海燕（Fregetta tropica）和Wilson’s风暴海燕（Oceanites oceanicus）在繁殖期的营养地位和饮食进行了研究，发现BBSP在更高营养地位的饲料比WSP消耗更多的鱼。此外，稳定同位素分析（SIA）揭示了它们的非繁殖运动。然而，迄今为止，它们的非繁殖营养地位和分布仍未得到充分研究。在这个项目中，我们计划以过去几十年开展的工作为基础，实施在试点项目和其他海燕物种中已经证明成功的方法。利用独立于基线的SIA、GPS和GLS标签，以及在南极洲乔治王岛采集的日粮内容元条形码和形态及繁殖参数数据，进一步揭示黑腹海燕和威尔逊风暴海燕的觅食和运动生态。我们打算使用不依赖基线的SIA来研究被研究物种在繁殖期间和繁殖期之外的营养地位，包括成年和雏鸡，并研究观察到的饮食和营养地位的差异如何影响繁殖成功。我们将在繁殖季节给成虫配备GPS标签，以便在繁殖期间发现觅食范围，并在非繁殖期给成虫配备GLS标签。我们的目标是测试物种之间营养位置的差异如何与鸟类及其猎物分布的差异联系起来，觅食生态在繁殖季节之间如何变化，以及与非繁殖季节相比如何。由于这方面的很多信息仍然未知，这项研究将为未来的行为变异性分析奠定基础。

Storm-petrels are among the world’s most abundant pelagic seabirds, and thus form an important part of marine ecosystems. However, due to their small size and pelagic lifestyle, their trophic ecology is hard to study, especially during the non-breeding period which they spend on the open ocean. The trophic position and diet of black-bellied storm-petrels (Fregetta tropica) and Wilson's storm-petrels (Oceanites oceanicus) during the breeding period has been studied previously, revealing that BBSP forages at a higher trophic position consuming more fish than WSP. Additionally, stable isotope analyses (SIA) have shed some light upon their non-breeding movements. However, their non-breeding trophic position and distribution have so far remained understudied. In this project, we plan to build upon the body of work carried out over the past decades, and implement methods already proven successful in a pilot project and other petrel species. Using baseline-independent SIA, GPS and GLS tags, metabarcoding of diet contents and morphological and breeding parameter data collected during the breeding season on King George Island, Antarctica, we aim to further unravel the foraging and movement ecology of black-bellied and Wilson’s storm-petrels. We intend to use baseline-independent SIA to study the trophic position of the studied species both during and outside of the breeding period, for both adults and chicks, and to study how differences in observed diets and trophic position affect breeding success. We will equip adults with GPS tags during the breeding season to discover foraging ranges during the breeding period, and with GLS tags to study the non-breeding movements. We aim to test how differences in trophic positions between the species are connected to differences in distribution of the birds and their prey, how the foraging ecology changes among breeding seasons, and how it compares to the non-breeding season. As much of this information is still unknown, this study will set a baseline for future analyses of behavioural variability.