Inland Fisheries

5.4.2.1.1 Fish and Fishery

The lake maintains an ideal ecological condition to harbour and nurture catadromous, anadromous and endemic species of fish and prawn and the Irrawaddy Dolphin (Orcaella brevirostris). There are 225 species of fishes belonging to 147 genera, 71 families and 15 orders. At present 35 species of fishes are commonly available in the lake of which 16 species are commercially important. They include Mugil cephalus, Liza troshelli, Lates calcarifer, Eleutheronema tetradactylum, Pseudosciaena coibor, Nematalosa nasus, Mystus gulio, Tenualosa ilisha, Tachysurus arius, Osteogeniosus militaris, Plotosus canius, Grenidens crenidens, Gerres setifer, Etroplus suratensis, Sparus sarba and Strongylura strongylura. Stomatopoda (2), Prawns and shrimps (24), Brachyuran crabs (28),Hermit crabs (6), Mollusca (136) have also been recorded from Chilka lake., The four commercially important prawn species, available in this lake are F. indicus, Penaeus monodon, Metapenaeus monoceros and Metapenaeus dobsoni. The important crabs available in this lake are Scylla serrata and Portunus sp.

For better monitoring practices, these 16 economic fish species can be classified as under based on their breeding and migration habits. Mullets (M. cephalus, L. macrolepis), S. sarba, L. calcarifer and C. crenidens are catadromus by nature. T. ilisha, N. nasus, P. coibor, T. arius, E. tetradactylum and G. setifer are having anadromous habit. M. gulio, O. militaris, P. canius, E. suretensis, G. setifer, Beloniformes and Tricanthus sp. are endemic to the lake.

It is evident from the catch composition that the catadromus and anadromus species occupy more than 80% of the total stock in the lagoon. Most of the catadromus species breed near the lake mouth or inshore water in the sea while the anadromus species breed in the lake areas where the rivers Daya, Nun and Bhargovi discharge their monsoon runoff. The endemic species enjoy the entire northern and central sectors of the lake and Satpara area for breeding purposes. Moreover, the lake has been found to be enriched with variety of natural fish and prawn feed viz., detritus, algae, zooplankton, insect larvae, fish and prawn larvae, periphytic organisms etc. to suit the aquatics in all stages of their life cycle and in all niches.

The very high percentage of prawn seed in the tow net collection is not reflected in the total yield of prawn, the most commercially important species whose food chain is mainly comprised crustacean, detritus and zooplankton. Mullets, in spite of dominating the larval population in the lake, contribute only 12.5% to 14.7% in the total output. The species mainly thrives on bottom biota, mud and algae. Though there is overwhelming abundance of food of prawn and mullets, the predators might be primarily responsible for the comparatively low yield. The Chilka is not a self contained lake. About 70 to 80% of its fish load depends on migration to sea. Abundance of migratory species in the lake mainly depends on the condition of the outer channel and unobstructed ingress and egress of water over the area from Satpara to Mugger Mukh. The low output in the extreme southern sector indicates inactive role of the Palur canal in the migration. Accordingly, low migration rate might be another cause of low output. Some species of freshwater (carps and murrels) enter the lake during the monsoon and are caught, forming about 1% of total catch which is estimated to be 4000 tonnes/yr.