ABSTRACT

New Zealand fur seals (Arctocephalus forsteri) are expanding in numbers and distribution throughout New Zealand. The exception is the West Coast of the South Island, where there is documented decline due to decades of mortalities related to fishery. There are fur seal colonies south of these West Coast colonies, in Fiordland, which have never been accurately documented or monitored. Even for those that are documented, there are few records of pup numbers and no population estimates. Here, pups at colonies from Doubtful/Pateā, Dusky, and Breaksea Sound, and Chalky Inlet were observed, and their numbers either counted directly or estimated using mark-recapture methods in February 2021. From these pup counts a coarse minimum population estimate of between 14–24 thousand fur seals is calculated for lower Fiordland. The pup counts and population estimates indicated the fur seal numbers are higher than previously recorded from estimates of walk through, boat or helicopter observations. During onshore surveys and from anecdotal evidence, it was noted that fur seals were rearing pups in forested areas. This paper outlines suggestions for the future monitoring of these colonies given, location, diverse geology and the difficulty of monitoring colonies on exposed west coast areas of New Zealand’s Fiordland.

摘要

新西兰毛皮海豹 ( Arctocephalus forsteri) 在整个新西兰的数量和分布范围内不断扩大。南岛的西海岸是个例外，由于几十年来与渔业有关的死亡率，那里有记录在案。这些西海岸聚居地以南的峡湾地区有毛皮海豹聚居地，这些聚居地从未被准确记录或监测过。即使对于那些有记录的，也很少有幼崽数量的记录，也没有人口估计。在这里，观察了来自 Doubtful/Pateā、Dusky、Breaksea Sound 和 Chalky Inlet 的殖民地的幼崽，并在 2021 年 2 月直接计算或使用标记-重新捕获方法估计它们的数量。根据这些幼崽计数，粗略估计的最小种群数量介于据计算，峡湾下游地区有 14–24 千只海狗。幼崽数量和种群数量估计表明海狗数量高于先前通过步行、乘船或直升机观察的估计记录。在陆上调查和轶事证据中，人们注意到毛皮海豹在森林地区饲养幼崽。本文概述了未来监测这些殖民地的建议，包括位置、多样化的地质情况以及在新西兰峡湾暴露的西海岸地区监测殖民地的难度。