Challenges of regulating commercial use of marine elapid snakes in the Indo-Pacific

Abstract
Marine elapid snakes are a diverse, predominantly Indo-West Pacific species group. The
persistent removal of some species has an unquantified but potentially dire impact on
populations. We conducted the first comprehensive review of the trade in marine elapid
snakes based on published literature (1974–2022) and trade data from the only species
(i.e., Hydrophis [Lapemis] curtus) whose trade is monitored internationally. Some species and
populations were subjected to targeted harvest for their meat and skins for at least the
last century; fisheries are possibly the most significant threat to populations of marine
elapids, with the highest numbers being exploited either accidentally, incidentally, or opportunistically
in Southeast Asian fisheries targeting other seafood, including demersal trawl
and squid fisheries. Southeast Asia is the core region for exploitation of marine elapids.
Annual offtake is >225,000 individuals of at least 8 species in the Gulf of Thailand. Of 72
recognized marine elapids (all non-CITES [Convention on International Trade in Endangered
Species of Wild Fauna and Flora] species), Hydrophis curtus and Hydrophis cyanocinctus
dominate the skin trade. Skins of H. curtus are traded mainly in East and Southeast Asia
and, to some extent, Europe. Despite some baseline information on the trade of these
species, the sustainability of their harvests, particularly in the context of the burgeoning
and unmanaged nature of fisheries in the region, remains the major challenge. In an era
of declining fish stocks, there has been an increasing trend to commercialize the harvest
and use marine elapids that were once considered accidental bycatch and discarded. This
trend will continue to pose a significant risk to these snakes unless appropriate fisheries and
trade regulations are enforced. Applying the precautionary principle to prevent the overexploitation
of sea snakes is an indispensable measure in which trade in regional populations
should be regulated through CITES. Accordingly, management plans to identify core distribution
regions of exploited species would be crucial for assigning national responsibilities
to sustain species and populations in the long term.