TITLE:
Decline in Diversity and Production of Exploited Fishery Resources in Vembanad Wetland System: Strategies for Better Management and Conservation
AUTHORS:
Chalil Veedu Asha, Payattukattil Sukumaran Suson, Cleetus Irumpanath Retina, Sivasankaran Bijoy Nandan
KEYWORDS:
Fishery Production, Macrobrachium rosenbergii, Ramsar Site, Vembanad Wetland System
JOURNAL NAME:
Open Journal of Marine Science,
Vol.4 No.4,
October
31,
2014
ABSTRACT: This paper describes the fishery catch structure
of Vembanad wetland system during August 2012 to July 2013. The estimates of fishery
production indicated an annual landing of 4387.31 t, in which 480.98 t
and 3906.33 t contributed by southern and northern zone of
Vembanad respectively. Eighty species of finfishes, five species of penaeid
shrimps, three species of palaemonid prawns and two species of crabs were
identified from the study period. The catch per unit effort (CPUE) value was
maximum for gill net (3.04 kg·h-1) followed by stake net (2.43 kg·h-1), Chinese dip net (2.01 kg·h-1), seines (1.2 kg·h-1), cast net (0.72 kg·h-1) and hook and line (0.34 kg·h-1). Biological integrity and fishery production
of estuaries in the country are declining mainly due to various man induced
activities. Thaneermukkom barrage, the salinity barrier, constructed across the
Vembanad wetland system in 1976, transforming the water
body into two distinct ecosystems, a fresh water zone on the south and a
brackish water zone on the north, resulting in gross changes in physical,
chemical and biological entity of the aquatic ecosystem. In the southern zone
of Vembanad the marine fish species were less available with the closure of the
barrage period. There are signs of decline of the Vembanad fishery resources, evident in the
lesser number of species and decline of fishery production. This will lead to
biodiversity loss, fish stock reduction and will ultimately affect the livelihood support of the
traditional fishers to a large extent, besides affecting other ecological
services. A better conservation measure must be implemented for maintaining the
sustainable fishery resources in Vembanad.