The participatory actions of artisanal fishers reveal spatial–temporal trends of seahorse catches as basis for future management

Although artisanal fisheries is a source of livelihood for millions of people worldwide, the lack of monitoring makes it difficult to assess under which contexts this practice is sustainable. This is critical when it comes to endangered species, such as seahorses, which are commonly caught by small-scale fisheries. Over a period of four years the illegal seahorse fisheries were monitored via participatory actions. Hippocampus reidi is an International Union for Conservation of Nature (IUCN) protected species and legally protected in Brazil. This species is nonetheless widely captured in the study region (Todos os Santos bay - Brazil), the targets mainly being mature and brooding individuals. This study tallied a total of 5763 seahorses that were caught in artisanal fisheries. Through participatory monitoring, seahorse habitat preference was shown as followed: seagrass—49.3% of the catches, and mangroves—29.7%. Likewise, the main gear selected for capturing these fish was seine nets, with 68.7% of all capture. Size and sex of captured individuals varied over spatial and temporal scales, despite consistent catch per unit effort (CPUE) over the years at the different fishing sites. Using maximum likelihood of occurrence, these results revealed that the skills required by fishers to catch seahorses involved spatial acuity. This illegal practice appears to persist because of several factors, including the absence of surveillance by governmental agencies, low fisher awareness, and high trade value of seahorses in parallel markets. The findings of this study may facilitate the inclusion of local stakeholders in monitoring, managing, and protecting these endangered species that remain the focus of an active fishery sector.