Egg production, hatching, faecal pellet production of Calanus finmarchicus in the North Atlantic

The samples were collected using a T-80 net (375 µm mesh size) equipped with a non-filtering cod-end in the North Atlantic during the G.O. Sars Trans-Atlantic cruise in 2013. Within 15-30 minutes after the recovery, 20 Calanus finmarchicus females were sorted out under microscope in ice chilled petri dishes and incubated individually in 600 ml polycarbonate culture bottles resulting in 20 replicate measurements. The bottles were filled with 50 µm screened seawater originated from 6 m water depth. The samples were incubated upright in thermoroom for 24 hours at the surface temperature (3°C). After the samples had been filtered (40 µm filter), female prosome length, egg as well as pellet abundance were determined. Subsequently, eggs from six females were incubated in petri dishes at 5°C. After 4 days, the number of nauplii and eggs were counted in order to calculate hatching success.

2013年G.O.萨斯（G.O. Sars）号跨大西洋科考航次期间，在北大西洋海域使用配备非过滤式囊网（non-filtering cod-end）的T-80型网（T-80 net，网目尺寸375微米）采集样本。样本回收后的15~30分钟内，在显微镜下于冰浴培养皿（ice chilled petri dishes）中分拣出20头雌性芬马克哲水蚤（Calanus finmarchicus），将其分别置于600毫升聚碳酸酯培养瓶（polycarbonate culture bottles）中培养，最终得到20组重复测量数据。培养瓶内注入取自6米水深、经50微米筛网过滤的海水。将培养瓶直立放置于恒温培养室（thermoroom）中，以表层水温（3℃）条件培养24小时。待样本经40微米滤膜（40 µm filter）过滤后，测定雌性个体的头胸部长度（prosome length）、卵囊数量及粪团丰度。随后，将6头雌性个体所产的卵置于培养皿中，于5℃条件下培养。培养4天后，计数无节幼体（nauplii）与未孵化卵的数量，以此计算孵化成功率。