Fisheries dependent biodiversity survey of Chondrichthyes in Gujarat, India

The Arabian Sea Region (ASR) is one of the most productive marine area and supports chondrichthyan species-sharks, rays, skates and chimeras. Western India falls in the ASR and contributes heavily to India’s chondrichthyan... [ view full abstract ]

The Arabian Sea Region (ASR) is one of the most productive marine area and supports chondrichthyan species-sharks, rays, skates and chimeras. Western India falls in the ASR and contributes heavily to India’s chondrichthyan exports.  Here, condrichthyans are targeted by fisheries and caught as bycatch. Chondrichthyes, play an ecologically important role in top-down regulation and structuring of marine ecosystems. Their slow generation time can make population recovery difficult under heavy fishing pressure. Their decline can negatively affect other commercial fisheries and cost millions of livelihoods. There has been a reported decline in the abundance of chondrichthyan catches in India in spite of increased fishing pressure. This likely indicates a decline in population abundance of Chondrichthyes resulting from intense unregulated fishing, habitat loss, and the shark fin trade. It is thus imperative to prioritize sustainable fishing practices and conservation of chondrichthyan populations. The western Indian state of Gujarat has the largest contribution (~40%) to India's chondrichthyan exports, thus making it a priority area for conservation and management of Chondrichthyes. Our objective is to study the seasonal biodiversity of chondrichthyan species found in Gujarat and to determine key ecological habitats through fisheries dependent sampling. Four main ports are chosen as field sites for this study. Seasonal sampling is done at each of these four sites in spring, summer, fall, and winter. Samples are species identified through molecular analyses. Our research has identified previously unidentified species. We expect these findings to help generate species distribution estimates and prioritize marine protected areas.