AAS 4087 Fulmarine petrel tracking study, Hop Island, 2015/16

The foraging ecology of three fulmarine petrels including Cape petrels, Southern fulmars and Antarctic petrels were investigated at Hop Island during the 2015/16 austral summer. Two datasets were generated: 1) tracking data from Fulmarine petrels, and 2) stable isotope analysis of blood, feathers and egg shells. Tracking data were collected using Ecotone GPS trackers attached to the birds back feathers with tape. Location data has been interpolated using great circle distance to a time step of 15 minutes and include a record of whether the bird dived during that time period or not. Each location point was assigned a breeding stage (incubation or chick rearing) based on individual nest activities. Stable isotope ratios of carbon (13C/12C) and nitrogen (15N/14N) were determined by analysing 1 mg aliquots through continuous flow - elemental analysis - isotope ratio mass spectrometry (CF-EA-IRMS). Isotopic values of blood reflect approximately the last 52 days before sampling and thus the incubation period of all three species. Egg membranes and feathers remain metabolically inert after formation, and hence reflect the trophic niche during the pre-laying and moult period, respectively. We collected moult feathers during the chick-rearing period and therefore assumed that these were formed one year prior to the collection date and thus represent the trophic niche of the chick-rearing period one year earlier (austral summer 2014-15).

2015/2016年南半球夏季期间，研究人员于霍普岛（Hop Island）针对3种管鼻类海燕（fulmarine petrels）的觅食生态学展开调查，涵盖海角海燕（Cape petrels）、南方管鼻鹱（Southern fulmars）与南极海燕（Antarctic petrels）。本研究共生成两类数据集：1）管鼻类海燕的追踪数据；2）血液、羽毛及卵壳的稳定同位素分析数据。追踪数据通过将Ecotone GPS追踪器（Ecotone GPS trackers）以胶带固定于鸟类背部羽毛采集获得。位置数据采用大圆距离法插值至15分钟的时间步长，同时记录了对应时段鸟类是否发生潜水行为。基于个体巢区活动情况，每个位置点均被赋予了繁殖阶段信息（孵卵期或育雏期）。通过连续流-元素分析-同位素比值质谱法（CF-EA-IRMS，continuous flow - elemental analysis - isotope ratio mass spectrometry）对1mg等分试样进行分析，测定了碳（¹³C/¹²C）与氮（¹⁵N/¹⁴N）的稳定同位素比值。血液的同位素值大致反映采样前约52天的营养状况，对应三种鸟类的孵卵期。卵膜与羽毛在形成后代谢惰性保持稳定，因此分别反映产卵前期与换羽期的营养生态位。本研究于育雏期收集换羽所得的羽毛，因此假定这些羽毛形成于采样日期的一年前，即代表一年前（2014/2015年南半球夏季）育雏期的营养生态位。