Chronological variation in landing of Indian Major Carp (IMC) of Ganga River

Abstract

During its course of 2,525 km, the River Ganga flows through the variant topography, ecological, and environmental conditions that harbor huge range of floral, faunal, and fish diversity. The ecological condition and biodiversity of upper, middle, and lower stretches of the river are different from each other. Increases in anthropogenic activities on Ganga have resulted in a decrease in quality and quantity of its water, which ultimately led to change in its biodiversity. Menon (1974) listed 141 fish species occurring in the Ganga River system belonging to 72 genera, 30 families, and 11 orders. Recent studies reported 143 fish species from the River Ganga (Das et al., 2014; Sarkar et al., 2011) including cold water, freshwater, and estuarine fishes. In this article, a critical comparison is made on the availability of an important fish group, the Indian Major Carp (IMC), of the Ganga River during different decades, starting from 1956 and annual yield between 2005 and 2018. Average annual IMC landing during 1955–1967 was recorded as 90.85 ton, with maximum (131.3 ton) during 1964–1965 and minimum (54.0 ton) in the year 1958–1959. There was generally an increasing trend of IMC landing during 2005–2018, but it has reduced to one‐third in comparison to the time period of 1956–1967. The analysis shows that catch as well as species composition of IMC had been changed over the period of time due to changes in hydrological regime and ecology of the river. The reason in totality of this change is a focused theme of this paper.

Decadal Shift in Fish Landings and Catch Composition in Brahmaputra River, Assam, India

“…During the period 1980-2019, the contribution by IMC towards total 2010) in this landing centre. The decline in IMC landings has also been reported for Ganga River system at Allahabad (Vass et al, 2009;Jha et al, 2020), reduced from 90.85 t (1956)(1957)(1958)(1959)(1960)(1961)(1962)(1963)(1964)(1965)(1966)(1967) to 25.61 t (2005-2018) (Jha et al, 2020). Local polynomial regression (LPR) of degree one was fitted to the annual IMC landings of river Brahmaputra at Guwahati.…”