The puzzle of the anchovy–sardine inverse fishery at the south‐eastern coast of the Arabian Sea and climate variability

Abstract

AbstractAn out‐of‐phase pattern of fishery between anchovy and sardine exists in upwelling systems of different geographical locations. We examined the inverse relationship of anchovy (Stolephorus sp., Engraulidae) and sardine (Sardinella longiceps, Clupeidae) fishery along the coast of the south‐eastern Arabian Sea (SEAS) by analysing the annual landing data of Kerala, Karnataka, and Goa states. Landings of anchovy and sardine showed wide fluctuations with distinct episodes of abundance and decline. We selected anchovy period (1984–1996) and sardine period (2000–2013) for close examination according to the environmental data availability. The study reveals that the observed inverse fishery along the coast of SEAS is well connected to regional environmental parameters and global climate variability. During the abundant anchovy period, the anomalies of surface currents were observed towards the north and also towards the coast during the spawning periods of anchovy (March–May, October–December). The pattern of surface current anomalies is reversed during the abundant sardine period. Anomalies of surface current is directed towards offshore during the early life stage of sardine (June–September), but it reversed towards the coast during the abundant sardine period. Similarly, an opposite upwelling pattern is noted in both species’ spawning seasons during the anchovy and sardine abundant periods. During these periods, the spatial distribution of global surface air temperature and wind anomalies showed contrasting spatial patterns and hence they are related to various climate indices in sardine and anchovy abundant periods in the SEAS.