Processed tracking data of Southern Giant Petrels during breeding activity in Harmony Point, Nelson Island, between 2021 and 2023

Processed GPS data for 36 Southern Giant Petrels (Macronectes giganteus) in December and January of 2021/22 and 2022/23 breeding season in Harmony Point (62°17′60″ S, 59°10′60″ W), Nelson Island, Maritime Antarctic Peninusula. All individuals had active nests. Bill size and tarsus length for 50 southern giant petrels ringed in the area. Between 2021 and 2023 50 breeding individuals were captured on the nest, following methods and protocols previously approved (https://zenodo.org/doi/10.5281/zenodo.10640094). For capture, one researcher approached the colony, while the others remained at a distance, preferentially out of sight of the birds. Response behavior to the approaching researcher was used as a proxy for capture selection, for instance, animals that regurgitate or stand on the nest exposing the eggs when the researcher approaches are more likely to leave the nest or might take longer to return to the nest after releasing, increasing the risk of breeding failure (Krüger et al. in prep). Therefore, animals displaying those behaviors were not captured. Before capture, the egg was gently removed from below the bird, covered in thermal tissue and put inside a box, for protection from cold and predation. Then the bird was captured by hand and taken to the site where other two researchers were waiting. Animals had their eyes covered with a head hood. All captured animals were ringed with stainless steel bands (rings), preferentially both animals from the same nest each season. All captured animals had bill and tarsus measured with calipers. Bill was used to determine sex, since males have larger bills with no overlap of measures with females. After release back to the nest, behavioral status of the animal was observed, and after the animal remained sat at the nest, the egg was placed back. GPSs were deployed on the back of the birds using 3M Extreme Hold Duct Tape 2835-B (1.88 inches) and Loctite glue. In 2021/22 and 2022/2023 seasons 30 and 20 birds were tagged with GPSs, respectively. In 2021/22, 4 females lost the GPS, and in 2022/23 one male and one female lost the GPS. Therefore there was tracking data for 26 and 18 animals, respectively. Eight animals were repeated in both seasons, totalizing 36 animals tracked in the two seasons. CatLog-P Gen 2 epoxy cased GPSs loggers (Perthold Technology, 50g) and Sputnik XAIS GPSs (Sextant technology, 70g) were used. Southern Giant Petrel weight varies between 4 kg and 6 kg, therefore the heavier instrumentation on the lighter birds would represent less than 2% of body weight, percentage which is accepted to have no significant effect on large procellariforms . Loggers were configurated to record one geographical fix each 5 minutes, and were recovered from the birds after 2 to 4 weeks. See https://github.com/drlucaskruger/SouthernGiantPetrel_Movements_and_Individual_Size for codes. This study was funded by INACH (Programa Áreas Marinas Protegidas 24 03 052) and ANID – Programa Iniciativa Milenio – ICN2021_002 (BASE).本数据集包含2021/22及2022/23年繁殖季的12月至次年1月期间，在南极半岛海域纳尔逊岛和谐点（62°17′60″ S, 59°10′60″ W）的36只南方巨鹱（Macronectes giganteus）的预处理GPS定位数据。所有研究个体均拥有活跃繁殖巢穴。此外还包含该区域环志的50只南方巨鹱的喙部尺寸与跗跖长度测量数据。 2021至2023年间，研究人员依照此前获批的方法与规程（https://zenodo.org/doi/10.5281/zenodo.10640094），在巢穴中捕获了50只繁殖个体。捕获流程为：一名研究人员靠近种群聚居地，其余人员保持安全距离，优先避免被鸟类察觉。以研究人员靠近时的行为反应作为捕获选择的替代指标：例如，当研究人员靠近时出现反刍或站在巢边暴露鸟蛋的个体，更有可能弃巢，或在被释放后更久才返回巢穴，增加繁殖失败风险（Krüger等，待刊），因此此类个体不予捕获。捕获前，需将鸟蛋从亲鸟身下轻轻取出，用保温材料包裹后放入箱中，以避免受冻与被捕食。随后徒手捕获亲鸟，并带至另外两名研究人员等候的地点，用头罩遮盖其眼部。所有捕获个体均佩戴不锈钢脚环，优先为每个繁殖季的同巢个体佩戴脚环。使用游标卡尺测量所有捕获个体的喙部与跗跖长度：由于雄性南方巨鹱的喙部尺寸大于雌性且无测量值重叠，因此通过喙部尺寸判断个体性别。将亲鸟放回巢穴后，观察其行为状态，待亲鸟重新蹲守巢穴后，再将鸟蛋放回原处。 使用3M Extreme Hold Duct Tape 2835-B（1.88英寸）胶带与乐泰（Loctite）胶水，将GPS设备安装在鸟类背部。2021/22与2022/23繁殖季分别为30只与20只个体佩戴了GPS设备。其中2021/22季有4只雌性个体的GPS设备脱落，2022/23季有1只雄性与1只雌性个体的GPS设备脱落，因此分别获得26只与18只个体的有效追踪数据。另有8只个体在两个繁殖季均被追踪，两个季度累计追踪个体共36只。本次研究使用了CatLog-P Gen 2环氧封装GPS记录仪（Perthold Technology，重50g）与Sputnik XAIS GPS设备（Sextant Technology，重70g）。南方巨鹱的体重范围为4kg至6kg，因此较轻个体背负的较重设备重量占其体重比例不足2%，该比例被认为对大型鹱形目（Procellariiformes）鸟类无显著影响。记录仪设置为每5分钟记录一次地理定位点，并在佩戴2至4周后从鸟类身上回收。 相关代码可访问以下链接查看：https://github.com/drlucaskruger/SouthernGiantPetrel_Movements_and_Individual_Size。 本研究由智利国家南极研究所（INACH，保护海洋区域项目24 03 052）与智利国家研究与发展局（ANID – 千禧倡议计划 – ICN2021_002（BASE））资助。