ICAR-Central Marine Fisheries Research Institute, Veraval Regional Station, Veraval 362269, Gujarat, India; ICAR-Central Institute of Fisheries Education, Fishery Resources Harvest and Post-harvest Division, Mumbai 400061, Maharashtra, India.
ICAR-Central Marine Fisheries Research Institute, Mangalore Regional Centre, Mangaluru 575001, Karnataka, India.
Sci Total Environ. 2023 Aug 15;886:163975. doi: 10.1016/j.scitotenv.2023.163975. Epub 2023 May 8.
Fish frequently shift their distribution ranges as a result of changes in preferred environmental factors. Knowledge on distribution of fish in relation to their environmental optima is crucial for improving the understanding of fishing grounds and planning sustainable exploitation. This study investigated the monthly variability in environmental factors impacting the catch rate and the spatio-temporal distribution patterns of fish along northwest coast of India (NWCI) from 2017 to 2019. The time series images of sea surface temperature (SST), sea surface height anomaly (SSHa), chlorophyll-a concentration (CHL), and euphotic depth (Zeu) indicate close coupling between bio-physical variables in the region. Generalized Additive Model (GAM) applied to the catch rate of mid-water trawlers found that CHL and Zeu were the most influential variables for ribbonfish distribution, while CHL and SST influence squid distribution and SST and SSHa influence cuttlefish distribution. The total deviation explained 37.70 %, 10.70 %, and 22.28 % in the final model for simulating the spatio-temporal distribution of ribbonfish, squid, and cuttlefish, respectively. Environmental factors were significant in the final GAM model (p < 0.05). Spatio-temporal distribution patterns of fishery resources from mid-water trawlers showed that they were related to biophysical changes in the northwest coast of India. The high catch rate was observed in the northern latitudes during the post-monsoon (October), the major fishing season in the region. However, it shrank and shifted to southern latitudes during the winter (January). This study could be adapted to nearby countries in the Arabian Sea region for an effective and useful tool to monitor and manage the fishery resources. Furthermore, it could aid in decision-making for policymakers and resource managers to formulate strategies for holistic marine fishery management and sustainable resource exploitation.
鱼类经常会因为其偏好的环境因素发生变化而改变其分布范围。了解鱼类与环境最佳条件的分布关系对于提高对捕捞区的理解和规划可持续开发至关重要。本研究调查了 2017 年至 2019 年期间印度西北海岸（NWCI）鱼类渔获率的月度变化以及鱼类的时空分布模式，以及影响渔获率的环境因素。海表温度（SST）、海面高度异常（SSHa）、叶绿素-a 浓度（CHL）和透光层深度（Zeu）的时间序列图像表明该区域生物物理变量之间存在紧密耦合。广义加性模型（GAM）应用于中层拖网渔获率发现，CHL 和 Zeu 是影响带鱼分布的最主要变量，而 CHL 和 SST 影响鱿鱼分布，SST 和 SSHa 影响墨鱼分布。最终模型分别模拟带鱼、鱿鱼和墨鱼时空分布的总偏差解释了 37.70%、10.70%和 22.28%。环境因素在最终 GAM 模型中具有显著意义（p<0.05）。中层拖网渔业资源的时空分布模式表明，它们与印度西北海岸的生物物理变化有关。在后季风（10 月）期间，渔获率在北部纬度较高，这是该地区的主要捕捞季节。然而，在冬季（1 月），渔获率下降并转移到南部纬度。本研究可以适用于阿拉伯海地区的邻近国家，作为一种有效和有用的监测和管理渔业资源的工具。此外，它可以为决策者和资源管理者提供帮助，制定综合海洋渔业管理和可持续资源开发的战略。
