Black Sea ichthyoplankton data from the 'BRIDGE-BS Dec 2022' cruise performed in December 2022

The dataset contains data from samples collected in December 2022 onboard of R/V Bilim-2, at different stations located in Turkish EEZ of Black Sea. The sampling was performed within the BRIDGE-BS project (EU H2020, grant agreement No 101000240). Ichthyoplankton samples were collected by towing a WP-2 net with a 200 µm mesh size and a 57 cm mouth diameter. Lead pieces were attached to the collector to minimize the displacement of the net with the currents. On windy days, the vessel drifted from the point where the net was lowered down. In both cases, the wire angle was calculated and the length of the wire was corrected to collect the whole water column. Hauls were made with a speed of 0.5 m/s to minimize the spilling out of the water. For the nearshore stations, the net was towed vertically from 4-5 m above the bottom to the surface. For the offshore stations, the net was towed from the start of an anoxic layer (sigma-t, 16.2 kg/m3). The gelatinous organisms were sorted from the sample in the plankton net. After sorted geletinous organism, samples were fixed with 5% borax-buffered formaldehyde in 250 ml bottles. In the Institute laboratory, fish eggs and larvae were sorted and counted with the help of Olympus SZ6-SZX12 stereoscopic microscopes. Identification of fish larvae based on morphometric and meristic characters was done at the lowest possible taxonomic level, according to Leis and Carson-Ewart (2000), Demir (1957, 1958, 1959, 1969), Mater ve Çoker (2002), Russell (1976), Rodriguez et al.(2017) and Vodyanitsky-Kazanova(1954). The data file is in OBIS format.本数据集涵盖2022年12月于黑海土耳其专属经济区（Turkish Exclusive Economic Zone, EEZ）内多个站位，搭载"毕林-2"号（R/V Bilim-2）科考船采集的样本数据。本次采样工作隶属于BRIDGE-BS项目（欧盟H2020计划，资助协议编号：101000240）。鱼类浮游生物（ichthyoplankton）样本通过拖网方式采集，使用网孔孔径200微米、网口直径57厘米的WP-2型浮游生物网。为降低海流对网具的位移影响，采样装置加装了配重铅块。大风天气下，科考船会偏离下放网具的初始站位。针对上述两种作业场景，均通过计算钢缆倾角并修正钢缆长度，以确保采集覆盖整个水层。拖网作业速度设定为0.5米/秒，以尽可能减少网内水体溢出。近岸站位的拖网为垂直拖网，从海底上方4至5米处上行至水面；外海站位的拖网则从缺氧层起始位置（西格玛-t参数：16.2 kg/m³）开始进行。首先从浮游生物网采集的样品中分拣出胶状浮游生物，完成胶状生物分拣后，样品将置于250毫升容器中，用5%硼砂缓冲甲醛溶液固定。在研究所实验室中，科研人员借助奥林巴斯SZ6-SZX12型体视显微镜对鱼卵与仔鱼进行分拣和计数。鱼仔鱼的鉴定依据形态测量学与分类学特征，尽可能以最低分类阶元完成鉴定，参考文献包括Leis与Carson-Ewart（2000）、Demir（1957、1958、1959、1969）、Mater ve Çoker（2002）、Russell（1976）、Rodriguez等人（2017）以及Vodyanitsky-Kazanova（1954）。本数据集文件采用海洋生物地理信息系统（Ocean Biogeographic Information System, OBIS）格式存储。