Bycatch, habitat loss threaten widenose guitarfish popn along state’s shoreline

Panaji: The critically-endangered widenose guitarfish doesn’t figure in the basket of Goa’s commercially important fish delicacies. Its depleting population, however, faces further threats largely due to an extraneous factor–getting trapped in fishing nets as bycatch.

Unlike the sting ray that is highly craved by locals and tourists alike for ambott tik—a table delicacy that embellishes the rice thali—widenose guitarfish (glaucostegus obtusus) populations have largely declined over the years due to unintended catching by both small and large-scale fishers.

But there is hope for this species to be included in IUCN’s red list. Researchers are working in collaboration with the forest department to study and monitor their populations along Goa’s shoreline in a long-term project. The research aims at assessing the distribution of this species from the family of guitarfish (glaucostegidae) to evolve conservation strategies.

“The forest department has reacted positively to our conservation plans and initially, we propose to identify critical guitarfish habitats across Goa,” said marine biologist and researcher Bryan Miranda.

Just over two years ago, Union govt included this species in Schedule 1 of the Wildlife Act, 1972, in a major boost to its conservation. Catching, selling, or consuming it has been made a criminal offence.

Conservationists cite coastal development and pollution as being issues which may have triggered habitat degradation.

The fish’s conservation in Goa assumes significance as large groups of them are found off the state’s coast. Juveniles of guitarfish, which have no value at all, get caught in small-scale fishery and their release could help sustain their populations.

“We feel that all elasmobranch species, including guitarfish that inhabit the coastal ecosystems need to be studied comprehensively and conserved,” said G B Sreekanth, fisheries scientist at CCARI-ICAR, Old Goa. Sharks, ray, and skate fish species are classified as elasmobranchs, being cartilaginous fishes.

Just four to five guitarfish species are found in India, but most ecological information on these species is based mainly on data gathered at fish landing sites. Assessment about a decline in their numbers may not be accurate, as many similar looking species are clubbed together and reported.

Conservationists, for this reason, are not sure about cascading effects if they are wiped off. “These species are an important part of the food web. They are considered mid to top level predators,” Miranda said.

That the highly threatened species has low commercial value weighs favourably for their conservation.

“Most of them are not targeted by small and large scale fishermen. Basically, we plan to monitor the extent of catch at various locations,” he said.

According to reports, they are caught all along Goa’s coast. In an interesting development, IUCN has classified Talpona and Galgibaga beaches as important shark and ray areas. “This indicates that these sites offer foraging and shelter habitats for elasmobranchs, especially especially guitar fish,” said Sreekanth.

Another critical factor is that they can survive outside water for some time—an important aspect to work out conservation strategies. “We plan to sensitise stakeholders while keeping in mind their needs as well, to promote live release as a potential conservation measure,” said Miranda.