Increase in Dolphinfish (Coryphaena hippurus) Fishing Success Off the North Coast of Puerto Rico during Hurricane Leslie

Abstract

Documenting how storms and environmental variability affect the population dynamics, trends, and abundance of dolphinfish (Coryphaena hippurus) on short temporal scales is important for improving dolphinfish resource monitoring, conservation, and management. Here, a multifaceted technique was used to document an abrupt increase in fishing success among small-scale fishing sectors off the north coast of Puerto Rico during the 2018 Hurricane Leslie event. Seven datasets were used to document this event, and each provided substantiating information, but the combination of vessel catch and effort and seven-day averages of floating-algae density (FD), derived from the satellite-based alternative floating algae index (AFAI) imagery, present the newest technique to monitor dolphinfish fishing success on short and near-real time scales. Results revealed vessel effort and FD co-occurrence, with several vessel tracks within FD coverage of .01%-0.4%. Catch records from outings confirmed landings of dolphinfish from Sargassum and during the episode, 87% of total dolphinfish catch occurred at Sargassum habitat, with the remaining associated with nearby fish aggregating devices (FADs). Scuba visual census and fish tracking provided additional evidence of dolphinfish abundance and movements associated with Sargassum and nearby FADs. The combination of these methods provided a new technique to support insight into documenting changes in fishing success for dolphinfish, a key pelagic fishery. Expanding the spatiotemporal coverage of these methods could lead to the underpinnings of robust dolphinfish (and other pelagic fish, e.g., tuna and billfish) resource monitoring, improving data collection, and enhansing regulatory and data reporting compliance among small-scale fisheries.