Abstract:
The present study was undertaken to generate an inventory of the
fin fish and shell fish of Batticaloa lagoon and to assess the impact of water
chemistry on the assemblages of fishes. A total of 5689 fish specimens were
collected, belonging to 62 species, representatives of 30 genera and 36
families. The species compositions of lagoons vary according to the physical
characteristics and salinity regime of the lagoon. Marine, marine-estuarine
and freshwater species were classified in each season (Dry and Wet season)
according to their capability to cope with salinity fluctuations. Etroplus
suratensis was the most abundant species (23.12%), followed by Oreochromis
niloticus (17.21%), Nematalosa nasus (14.55%) and Arius bilineatus (12.72%);
Forty-three percent (43%) of the collected species correspond to a eurihaline
marine component, followed by autochthonus species for truly brackish
water (22.5%), estuarine residents (17%), stenohaline marine (10.5%),
Seasonal migrant (4%), freshwater component (2.5%), and very few are reef
fishes (0.5%). Twenty species were transient visitors and thirteen species
were marine juvenile migrants comprising of 8% of total numerical
abundance. Seasonal changes of salinity also have a great impact on the fish
abundance and distribution of the lagoon. The information and observation
in this study will be useful in formulating management policies for the future
use of Batticaloa lagoon especially multi-usage of fisheries with other sectors.
