- Between 2015 and 2017, an estimated 13 million seahorses have been caught annually as bycatch in India.
- The highest catch and trade of seahorses occurred in the southern state of Tamil Nadu.
- Most seahorses were caught by nonselective fisheries such as trawls and seine nets operating close to the shore.
For the past two decades, the catch and trade of seahorses has been banned in India. However, a new study reveals that 13 million seahorses are estimated to have been caught in bycatch annually between 2015 and 2017. Most were caught by nonselective fishing gears operating at the bottom of sea and close to the shore in southern India. A similar study estimated 16.8 million seahorses were caught prior to the ban.
The findings suggest that the ban has not been effective in controlling seahorse extraction and add to growing concerns on the use of bans in the conservation of species accidentally captured in commercial fishing nets and hooks, which are referred to as ‘incidental catch’ or ‘bycatch’.
Study author Tanvi Vaidyanathan says that “while it appears that the ban has been successful in limiting the direct extraction of seahorses through diving, any alleviation in such pressures appears to have been offset by the increased intensity of non-selective fishing such as trawling in recent years.”
In 2001, seahorses were placed in Schedule I under India’s Wildlife Protection Act 1972 banning their extraction and trade. The following year, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) listed all seahorse species in Appendix II, which regulates the export of the species to ensure the protection of wild populations.
Bycatch of seahorses occurs around the world. Recent trade surveys estimated that 29 million seahorses were caught annually in Thailand; 16.7 million in Vietnam; and about 1.7 million in the Philippines.
Many countries believe the best way to conserve a species is to impose a ban on their extraction and trade, but the situation is tricky when bans are imposed on incidentally caught organisms, Vaidyanathan explains. “Since the extraction of fishes is rarely managed, fishers find it extremely difficult to identify incidental catch. The results of my work should motivate the large number of countries that have resorted to bans to consider other measures.”
Trisha Gupta, a doctoral student at the University of Oxford, who was not connected to the study, is not surprised by the findings. “If a species is incidentally captured in fishing gear, protecting the species and banning its capture is going to do very little — it will continue to come as bycatch.”
Until now, most studies on the impact of bans have focused on larger charismatic species, Vaidyanathan points out. Sharks are also often captured incidentally and bans may be equally ineffective in conserving them, says Gupta, who is studying the conservation of sharks and rays in India. “We need to move away from stand-alone bans in these situations, and towards a more holistic approach to tackle bycatch in fishing and reduce its impacts,” Gupta adds.
The case of Tamil Nadu
Vaidyanathan, a doctoral student at the University of British Columbia, conducted extensive surveys along India’s coastline to gather data on fishers’ awareness of the ban, the number and fate of seahorses caught, method of capture, species caught, prices at which seahorses were sold along with other information. A total of 1145 structured and semi-structured interviews with fishers were carried out in nine states and two Union Territories during three time periods from July 2015 to September 2017. The first time-period covered the entire coastline of India while the second and third focused on Tamil Nadu.
Tamil Nadu (including Puducherry) emerged as the state with the highest catch where a median of 75 percent of the annual seahorse catches occurred, followed by Orissa (16.8%) and Andhra Pradesh (3.4%). Most fishers in Tamil Nadu reported selling seahorses. Eighty-nine percent of seahorses were caught by nonselective fishing gear such as trawls and seine nets (specifically drag nets) operating at the bottom of the sea from shallow waters of the Palk Bay region of Tamil Nadu. In 1999, before the ban, 68 percent were caught by nonselective fishing gear.
Trading of seahorses also occurred primarily in Tamil Nadu where they have traditionally been traded. Most fishers (>90%) in the state were aware of the ban as they brought up the topic without any prompts. While the government has been successful in raising awareness of the ban, it has not converted into conservation actions, explains Vaidyanathan, noting that awareness is likely offset by its profitability for those willing to take risks. “Illegal trade continues, but this trade has now been pushed underground.”
Preventing seahorse bycatch
“We need to protect key habitats and constrain fishing pressure, particularly from non-selective fisheries,” says Vaidyanathan. Rather than waiting for ‘perfect data,’ Vaidyanathan says “it is critical to start at least some measures of conservation as soon as possible.” Presently, critical seahorse habitats such as seagrasses are not protected. “This must be implemented,” she says, adding that “there should also be a strict implementation of no-trawl zones.”
In the Palk Bay region, large numbers of seahorses are caught by drag netters, which are traditional modified shrimp trawls, scouring seagrass beds for shrimp. Reducing the bycatch of seahorses may also affect the catch of economically useful species. “We must work on creating selective fisheries that provide more durable food security and economic resources,” says Vaidyanathan. To limit the catch of seahorses, Vaidyanathan suggests traditional draggers to establish community-based protected areas over sensitive seagrass habitats, while also curtailing mechanized trawl activities in the state.
“Gear modification measures are often recommended as one of the main means of avoiding the incidental capture of organisms,” notes Vaidyanathan. But this measure, she points out, does not consider what happens when the protected species (seahorses) are the same size as the targeted organisms (shrimp). “While it may be possible to develop effective Turtle Excluder Devices (TEDs), it will be really difficult for gear technology to reduce the bycatch of seahorses, or the many hundreds of other species incidentally caught in fishing nets.”
“Any bycatch reduction measure has to be developed alongside the fishing community, with their participation and inputs,” stresses Gupta. “Possible solutions can range from releasing live seahorses captured in nets, to modifying fishing gear and grounds to reduce their capture,” she suggests, noting that “as long as it’s developed with fisher participation, there’s a higher change of actually achieving the conservation objectives for these species.”
“Ultimately, if we can protect marine resources such as seahorses and their habitats in shallow waters,” Vaidyanathan hopes “we might have greater success in extending our conservation aspirations.”
Vaidyanathan, T., & Vincent, A. C. J. (2021). State of seahorse fisheries in India, nearly two decades after they were banned. Biodiversity and Conservation, 30(7), 2223-2253.
Banner image: A trawl landing site in the Palk Bay region of Tamil Nadu, where most seahorse catches were reported. Photo by Tanvi Vaidyanathan/Project Seahorse.