Observations of seabirds in Macquarie Island waters (1999)

<p>This survey is a first attempt at determining the distribution and relative abundance of all seabird species occurring in Macquarie Island waters, especially in relation to the main bathymetric and oceanographic features of the study area, namely the Macquarie Ridge and Subantarctic Front, respectively. To this end, observations of seabirds were made from aboard the CSIRO Research Vessel Southern Surveyor while it conducted acoustic, trawling and benthic surveys in the waters immediately round Macquarie Island and northwards along the Macquarie Ridge during 14-31 January 1999.</p>
<p>The nine main sites within the study area and the distribution of seabird counts at each site are shown in Figure 1 (see Appendix 4 of https://www.frdc.com.au/project?id&#61;1942). Most observations were made over the relatively shallow waters of the main part of the Macquarie Ridge i.e. close inshore off the east and west coasts of the island and northward along the ridge to the southern edge of the Subantartic Front Gap (sites 2-5). Additional observations were made in shallow waters well south of the island at the southernmost part of the ridge (site 7), and at two other ridge sites north of the Subantarctic Front Gap (sites 8 and 9). Observations were also carried out at two deep-water (pelagic) sites: at site 6 in waters c.25 miles west of Aurora Trough, and at the Subantarctic Front Gap (site 1) immediately north of the main north-south ridge through the island.</p>

本调查旨在首次确定所有在麦夸里岛水域出现的海鸟物种的分布及其相对丰度，特别是与研究区域的主要地形和水文特征，即麦夸里脊和亚南极锋的相关性。为此，研究人员在1999年1月14日至31日期间，乘坐澳大利亚联邦科学和工业研究组织（CSIRO）的“南方巡视者”研究船，对麦夸里岛周围及其沿麦夸里脊北向水域进行了声学、拖网和底栖调查的同时，对海鸟进行了观测。研究区域内包含九个主要站点，以及每个站点海鸟计数分布情况如图1所示（详见https://www.frdc.com.au/project?id=1942的附录4）。大部分观测是在麦夸里脊主体部分相对较浅的水域进行，即岛屿东西海岸附近以及沿着脊向北至亚南极锋缺口南缘（站点2-5）。在岛屿南端脊的最南端（站点7）以及亚南极锋缺口北部的两个脊站点（站点8和9）也进行了额外观测。此外，在两个深海（浮游）站点也进行了观测：在距离奥罗拉海沟约25英里处的站点6，以及岛屿主南北脊北部的亚南极锋缺口（站点1）。