Local Fishers' Knowledge of Target and Incidental Seahorse Catch in Southern Vietnam

Many vulnerable marine species are caught in small-scale fisheries that lack long-term records, thereby limiting the development of effective evidence-based management measures. To uncover recent trends in fish landings and value in the absence of historical data, we interviewed 77 fishers and five buyers on Phu Quoc Island in Southern Vietnam regarding their current and past fishing practices, with a focus on seahorse catches. Seahorses (Hippocampus spp.) are caught using multiple gear types (including trawls, crab nets, and compressor diving) and have both cultural and financial value. Most fishers catch seahorses incidentally, though 14 targeted them and made the majority of their income from their sale. Fishers reported that seahorse catch rates decreased by 86-95% from 2004 to 2014, while landed value simultaneously increased by 534%. If these reports are accurate, seahorse fishing on Phu Quoc is unsustainable and requires immediate management controls.