Zooplankton in lakes and fiords along the northern coastline of Ellesmere Island (Ward Hunt Island observatory)

Zooplankton was sampled from Lake A on 8 June 1999 and Disraeli Fiord on 9 June 1999. At Lake A, a hole was cut through the ice and was kept open for 3 days before zooplankton sampling. A 1-m-long conical plankton net mesh size 100 μm; mouth diameter 20 cm) was used to sample the zooplankton. Duplicate net tows were made sequentially at the following depths: 2.5, 5, 7.5, 10, 12.5, 15, 17.5, 20, 25, and 30 m. The net was towed by hand vertically at approximately 1 m/s from a given depth to the surface. In Disraeli Fiord, logistical constraints allowed us only a single tow from the brackish-water layer, from 30 m to the surface. All samples were preserved with final concentrations of 0.2% glutaraldehyde and 0.02% formaldehyde, a preservative used for phytoplankton studies but which gave very good preservation of zooplankton. The specimens were identified and enumerated using a binocular microscope (X32 magnification). At Milne Fiord, two zooplankton vertical tows (14-0 m then 50-0 m, through the same hole) were made on 4 July 2009 with a 39-cm-long net with a 210-um mesh size and diameter of 13 cm. The zooplankton samples were preserved with formaldehyde (final concentration 10%), and all individuals were then counted and identified to species level using a binocular microscope.

1999年6月8日于A湖、1999年6月9日于迪斯雷利峡湾（Disraeli Fiord）开展浮游动物采样。在A湖，研究人员先在冰层凿出孔洞并维持开孔状态3天，随后开展浮游动物采样。本次采样使用长1m的锥形浮游生物网（网目尺寸100μm，口部直径20cm），按2.5、5、7.5、10、12.5、15、17.5、20、25、30m的深度顺序依次完成两组平行垂直拖网。拖网以约1m/s的速度手动完成，采样路径为指定深度至水面。
在迪斯雷利峡湾，受后勤条件限制，仅能开展一次从咸淡水层30m至水面的垂直拖网采样。所有样品均采用终浓度0.2%戊二醛与0.02%甲醛的混合固定液固定——该固定液虽常用于浮游植物研究，但对浮游动物同样具备极佳的固定效果。样品通过放大倍数为32倍的双目显微镜进行物种鉴定与个体计数。
2009年7月4日于米尔内峡湾（Milne Fiord），研究人员通过同一冰层孔洞完成两次浮游动物垂直拖网采样，采样层次分别为14~0m与50~0m；所用采样网长39cm，网目尺寸210μm，口部直径13cm。浮游动物样品采用终浓度10%的甲醛溶液固定，随后通过双目显微镜对所有个体进行计数，并鉴定至物种水平。