By-catch mortality of beaked Sea Snake Hydrophis schistosus (Daudin, 1803) by entanglement in shore-seine operation in Goa-India

Abstract

Hydrophis schistosus (Daudin, 1803) commonly known as beaked sea snake occurs in shallow marine and estuarine habitats of India. The population of H. schistosus has been frequently noted in the shore-seine net as By-catch. Only a few studies are available about By-catch of sea snakes in Indian coasts. Being a top predator, their mortality and ecological consequences are largely unknown. The present study was conducted along the Caranzalem-Miramar coast of Caranzalem bay, Goa during monsoon (August-September, 2017 and 2018) to focus on the by-catch mortality of H. schistosus and their feeding preferences. Observations indicated that the fishing activities, particularly during every shore-seine operation, results in a significant by-catch of sea snakes where approximately 20–60 individuals get entangled in the fishing net. The study indicated a large number (90%) of juveniles being caught in the shore-seine. Gut content analysis of H. schistosus revealed that 80% of snakes preferred catfish Arius jella as the desired prey species. Sea snakes being top predator play a vital role in checking the local catfish population. Hence, in concern to save H. schistosus population and sea snakes, in general, the fishing methods, as well as awareness towards conservation of sea snakes among fishermen, should be raised.

Keywords

• Sea snake
• Hydrophis schistosus
• Arius jella
• by-catch
• Goa; India