Sri Lankan marine fishery resources were not assessed and updated for the last four decades. A comprehensive survey was performed by R.V. Dr. Fridtjof Nansen, starting from June 24 to July 16, 2018. Variations of fish density and diversity on the continental shelf of Sri Lanka were determined by region (East and West) and depth (20–50 m and 50–100 m) using 65 trawl samples collected. Associations between ichthyofauna, ecological parameters, and hydrographic variables (temperature, salinity, and oxygen) were determined. There were 620 species from 137 different families observed during the survey, with family Myctophidae being the most dominant with the highest number of individuals caught from all station (24.61% out of the total number of individuals) while the most represented families by density (t/NM²) were Carangidae (8.01%). A total of 440 species were found in the East region compared to 385 species in the West region; the density of fish was 1.3 times higher in the East region (9.00 ± 1.08 t/NM²) compared to the West region (6.85 ± 1.40 t/NM²). Similarly, the East region was 1.3 higher in the Shannon Wiener’s Diversity Index (SWDI) than the West region. Shallow-water (20–50 m) area has been reported as more diverse and denser than deep-water (50–100 m). Canonical correlation analysis showed a positive association of fish density with oxygen and a negative with temperature and salinity. This study would be an invaluable baseline for monitoring future changes and preparing recommendations and management action plans.

斯里兰卡的海洋渔业资源在过去四十年中没有得到评估和更新。RV Fridtjof Nansen博士于2018年6月24日至7月16日进行了全面调查。斯里兰卡大陆架上鱼类密度和多样性的变化取决于区域（东西方）和深度（20–50） m和50–100 m）使用收集的65个拖网样本。确定了鱼鳞鱼，生态参数和水文变量（温度，盐度和氧气）之间的关联。在调查中观察到137个不同科的620种，其中Myctophidae科是最主要的科目，被所有站点捕获的个体数量最多（占个体总数的24.61％），而按密度（t / NM ²）是Carangidae（8.01％）。东部地区共发现440种，而西部地区共发现385种。东部地区（9.00±1.08 t / NM ²）的鱼密度是西部地区（6.85±1.40 t / NM ²）的1.3倍。同样，香农维纳多样性指数（SWDI）的东部地区比西部地区高1.3。据报道，浅水（20–50 m）地区比深水（50–100 m）地区更加多样化和密集。典型相关分析表明，鱼的密度与氧气呈正相关，与温度和盐度呈负相关。这项研究将是监测未来变化以及准备建议和管理行动计划的宝贵基准。