Elasmobranch conservation, challenges and management strategy in India: recommendations from a national consultative meeting

Historically, India has been projected as one of the major elasmobranch fishing nations in the world. However, management and conservation efforts are not commensurate with this trend. Along with the Wildlife (Protection) Act, 1972, several generic conservation measures are in place at the regional/local level. But India is still a long way from meeting global conservation commitments. We present here the status of elasmobranch management and conservation in India, with the specific objec-tive of identifying the gaps in the existing set-up. We also present recommendations based on a national consultative workshop held at the Central Marine Fisheries Research Institute, Kochi, in February 2020. We recommend the implementation of a National Plan of Action (NPOA-Sharks) and more in-clusive governance and policymaking for elasmobranch conservation in India

Discontinuous distribution of <i>Alepisaurus ferox</i> Lowe, 1833 (Alepisauridae, Teleostei) in the Indian EEZ as revealed by the tuna longline survey

406-414Distribution pattern of longnose lancetfish, Alepisaurus ferox Lowe, 1833 in the Indian Exclusive Economic Zone had been analyzed for the period January 2005 to December 2007. While longnose lancetfish is caught from almost all the areas surveyed in the Bay of Bengal and Andaman and Nicobar waters, it is is not caught from areas north of latitude 16°24¢N of the Arabian Sea. Discontinuous distribution of longnose lancetfish in the Indian EEZ can be related to the existence of perennial Oxygen Minimum Zone in the northern Arabian Sea. Present study also consists the results of preliminary studies on the biology of this species

Ontogenetic and seasonal variations in the feeding ecology of Indo-Pacific sailfish, <i style="mso-bidi-font-style:normal">Istiophorus platypterus</i> (Shaw, 1792), of the eastern Arabian Sea

593-605Present study consists the studies on the stomach contents of Indo-Pacific sailfish, Istiophorus platypterus (Shaw, 1792), caught during tuna longline survey conducted in the western Indian EEZ (eastern Arabian Sea) between 2006 and 2009 to investigate the sexual, ontogenetic and seasonal effects in the diet. Stomachs of 290 specimens in the forklength range of 101-261 cm were examined, of which 38 (13.10%) were empty. Prey composition was assessed in terms of occurrence by number, frequency of occurrence, weight and Index of Relative Importance. Quantile regression techniques were used to determine the mean and upper and lower bounds of the relation between prey size and sailfish length. Diet was dominated by teleost fishes, followed by cephalopods while crustaceans were represented in limited instances. Purpleback flying squid, <i style="mso-bidi-font-style: normal">Sthenoteuthis oualaniensis, was the most preferred prey species. Other important prey species identified were <i style="mso-bidi-font-style: normal">Euthynnus affinis, Cubiceps pauciradiatus, Gempylus serpens and Onychoteuthis banksii. Diet did not varied by sex, but the ontogenetic and seasonal variations in diet were significant. The maximum and mean size of prey increased with length of sailfish. However, relatively smaller prey constituted bulk of sailfish diet and even large specimens consumed small prey. </span

Diversity, abundance and size structure of pelagic sharks caught in tuna longline survey in the Indian seas

26-36<span style="font-size:9.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" "times="" roman";mso-ansi-language:en-us;mso-fareast-language:en-us;="" mso-bidi-language:ar-sa;mso-bidi-font-weight:bold"="" lang="EN-US">Diversity and abundance of pelagic shark bycatch in the tuna longline operations in northern Indian Ocean were examined for the period 2004-2010.  During the survey 1.2 million hooks were deployed in three regions of seas around India resulting in the catch of 1501 numbers of sharks. Significant variations in the diversity and abundance of pelagic sharks were observed among the three regions of Indian seas. Catches of sharks are prominent in Andaman & Nicobar region contributing 35.15% of the catch by number and 51.46% by weight. In the eastern Arabian Sea, sharks constituted 15.49% and 14.89% of the total catch by number and weight respectively.   In western Bay of Bengal, this group contributed 7.74% (by number) and 9.33% (by weight) to the total catch. Alopias pelagicus, <i style="mso-bidi-font-style: normal">Carcharhinus limbatus, Alopias superciliosus and Carcharhinus falciformis were the dominant species of pelagic sharks observed in the Indian seas. Time series analysis of hooking rates revealed drastic decline in the abundance of pelagic sharks in the Arabian Sea as well as Bay of Bengal. </span

Oceanographic preferences of yellowfin tuna (Thunnus albacares) in warm stratified oceans: A remote sensing approach

Yellowfin tuna (Thunnus albacares, Bonnaterre, 1788; YFT) face extensive exploitation pressure worldwide owing to the attractive economics of these fisheries. A better understanding of how oceanography influences the distribution of YFT (or highly migratory species more generally) will improve the ability for fisheries management policies to achieve conservation (e.g., maintain a stocks reproductive capacity), economic (e.g., maximize gross domestic product), and social (e.g., optimize successful fishing opportunities) objectives. Such ecosystembased linkages, when combined with real-time remote sensing data, provide the predictive framework for enhancing favourable fishing opportunities and limiting excessive harvest. We examined factors influencing YFT distribution and behaviour using pop-up satellite archival tags and remotely sensed oceanographic data from two regions in the northern Indian Ocean. Tagged individuals did not exhibit significant deep diving or diurnal behaviour, and preferred ambient temperatures of 26–30°C and 25–29°C in the Arabian Sea (AS) and the Bay of Bengal (BoB), respectively. In general, tagged YFT were found to be in waters with sea surface temperatures of 26–29°C, 60% of the time andwithin a sea surface height-anomaly of ±6 cm 70% of the time. YFT avoided moving below the relatively shallow oxycline depth, which is indicative of the stratified waters of the AS and the BoB. Low dissolved oxygen levels are likely a limiting factor for tuna movement given their high oxygen demand. The northern Indian Ocean provides an opportunity to study climate impacts on fish distribution and movement, and our findings provide a basis for understanding how habitat and migratory patterns may be altered under climate change