Catch and trade bans for seahorses can be negated by non-selective fisheries

All seahorse species (genusHippocampus)are listed under Schedule I of India's Wild Life Protection Act, making all capture and trade of seahorses illegal. In the more than 15 years since the ban, little work has been done to assess its effects on seahorse conservation. Between 2015 and 2017, fisheries and trade surveys were conducted along the south-east coast of India, in the state of Tamil Nadu, historically known to be a hub for seahorse catches and trade. Seahorses were primarily landed as bycatch, although in greater quantities by traditional drag nets than as trawl bycatch. Total annual catches were estimated between 4.98 million and 13.64 million seahorses, 87% of which were caught by active non-selective gear. Generalized additive models revealed that seahorse catch per unit effort had non-linear relations with depth and latitude, and were higher in biogenic habitats, with active, bottom-used, and non-selective gears (e.g. trawls). The illegal nature of the trade in seahorses hampered an understanding of trade routes and trade volumes. Catch estimates indicated that 11.21-30.31 tonnes of seahorses probably entered trade, yet interviews with traders only documented trade of about 1.6 tonnes. Fishers reported a decreasing availability of seahorses. Since most seahorses come from bycatch in persistent fisheries that are not directly affected by the ban on seahorse capture, this decline is likely to represent a population decline. A fishery and trade ban for incidentally caught species, particularly in a poorly regulated fishery, appears to add little conservation value. There needs to be a shift in the management approach, moving from a ban towards spatial and temporal restrictions, and toward enforcing existing fishery regulations.

Automated summary

All seahorse species are protected under India's Wild Life Protection Act, with a ban on capture and trade. Despite little assessment on the ban's impact, surveys in Tamil Nadu revealed high numbers of seahorses caught as bycatch, primarily through non-selective gear. Illegal trade hindered understanding of trade routes and volumes, while declining availability suggested a population decline due to incidental capture in unregulated fisheries. A shift towards spatial and temporal restrictions in management is needed for effective conservation.