Assessment of fisheries and management in Rihand reservoir, Uttar Pradesh.

Abstract

The study assesses the present status of fisheries in Rihand reservoir in relation to past status in terms of fish species diversity, trophic metrics of fish community, trends in fish catch and the physico-chemical properties of the water body. Species-wise monthly catch data collected from annual fish catch records of Department of Fisheries, Rihand office helped analyse present the status. Shannon-Wiener Index showed an appreciable decline in species diversity between 1971-72 (H=2.94) and 2015-16 (H=2.59). There was significant loss in species richness during the same period as it has declined from 40 species, 28 genera and 11 families (1971-72) to 22 species, 16 genera and 8 families (2015-16). Seasonally, the species diversity was found to be at its peak during monsoon season (H=2.2), coinciding with favourable conditions such as sufficient water and ample food resources. Species richness was at its best in the month of May-June while species evenness (J=0.85) was highest in post monsoon indicating an evenly distributed and rich fauna in the monsoon and post monsoon periods. The review of literature on water quality status indicated the reservoir is meso-eutrophic in nature. The trophic metrics analysis has shown that the water body is dominated by herbivores, detritivores and omnivores (72.3%) followed by mid-level carnivores (26.7%) indicating gaps at the top level predators. The total fish catch of the reservoir has increased marginally from 152 tons in 1971 to 262 tons in 2016. The corresponding unit catch was 5.06 kg/ha/year and 8.68 kg/ha/year respectively, which is still very low. The CAGR of fish landings for the recent period (2000-01 to 2015-16) was found to be a modest 1.8% with several inter-year fluctuations. Given the conducive aquatic environment and moderate productivity levels of the reservoir, fish catch can be increased significantly only through sustained stocking program alongside effective governance.