Assessment of stock vulnerability of Indian marine fishes to past changes in climate and options for adaptation

Abstract

Vulnerability assessment frameworks are used in many countries to provide a primary assessment status of marine fish stocks and their susceptibility to change in response to external factors. With increasing evidence that the marine fisheries of India are likely to face major impacts of changing climate along with other natural and anthropogenic factors, a study was carried out to determine the relative vulnerability of 68 species of finfish and shellfish along the Indian coast. Species selection was based on their abundance and importance in the fishery across 4 zones in the country (northeast, northwest, southeast and southwest) and on biological characteristics like growth, reproduction and predator–prey interactions. Vulnerability assessment was based on the relation between exposure, sensitivity and adaptability attributes, expressed as V = (E + S) − A. The exposure attributes selected were environmental parameters that have a direct impact on the fish stocks. Sensitivity attributes were biological characteristics that are indicative of the ability or inability of the species to respond to external pressures. Adaptive capacity attributes were biological and ecological traits that could help the species to adapt to a fluctuating or changing environment. About 69% of the species studied are highly vulnerable along the Indian coast, with their susceptibility being higher along the east coast. Fishing pressure contributes significantly to stock fluctuations and reproductive output. Species with restricted geographic distribution are especially vulnerable to climate change. The outcome of this study will serve as an effective tool in prioritizing mitigation and fishery management strategies on a regional basis in the country.