Mapping Fishing Effort: Insights from the Ross and Amundsen Seas. Utilising Global Fishing Watch Data to Analyse Fishing Effort in the Ross and Amundsen Seas: a valuable aid for Sustainable Ocean Governance

This paper demonstrates the use of publicly available data from Global Fishing Watch (GFW) to analyse fishing activity in the Ross and Amundsen Seas during the 2024/25 season. Using satellite-derived Automatic Identification System (AIS) data, vessel movements were assessed to identify apparent fishing effort (AFE) and differentiate genuine fishing events from other activities, such as navigating through sea ice or waiting for grounds to clear. A filtering process was applied to refine the initial data, incorporating depth restrictions and historical fishing footprints. Fishing effort was categorised into three likelihood levels: possible, probable, and high-density fishing areas. The analysis revealed spatial and temporal patterns of fishing effort, highlighting the intensity of fishing in specific zones, such as the Mawson Bank in the Ross Sea and designated research blocks in the Amundsen Sea. The analysis also includes examples demonstrating the impact of sea ice on fishing operations, highlighting how ice coverage can impede access to fishing grounds and influence day-to-day activities. ​The findings emphasise the utility of publicly available GFW data, when combined with fishery-specific knowledge, and would be beneficial in characterising seasonal and inter-seasonal variations in fishing activity within the CAMLR Convention Area. This study provides an initial framework for leveraging this open-access data to improve our understanding of CCAMLR-managed fisheries. Future work could involve collaboration between the CCAMLR science community and GFW to refine algorithms for assessing demersal longline catches and enhance the accuracy of fishing effort estimates.