Qualitative study of fin fish and shell fish fauna of Thane creek and Ulhas river estuary
Abstract An attempt has been made to obtain the comparative fin fish and shell fish fauna qualitatively from Thane creek and Ulhas river estuary durin Nov 2001 to Oct 2002 dividing each of these two coastal water bodies into three zone (Riverine zone I, Middle zone II, Seaward zone III). Although the total number of species found in the Thane creek was high (67 spp.) as compared to Ulhas river estuary (58 spp.) the upper zone (I & II) of the former and zone I of later contain very low density of fish fauna. The salinity trend of zone-I of Thane creek is fairly nearer to zone-II od Ulhas river estuary but there is considerable difference in the fishery composition. It seems that various human activities like industrial effluent, domestic waste disposal, reclamation, sand dredging and eradication of mangrove flora have deteriorated these dynamic habitats causing decline in in their fin fish and shell fish fauna during last two decades. It has been observed that the mudskippers, prawns have completely eradicated from the entire stretch of the Thane crrek due to heavy industrial and domestic waste disposal although there is fairly good mangrove vegetation along its west bank. In case of Ulhas river estuary the sand dredging, occurring on its southern bank has forced the bottom dwellers like mud skippers, prawns & crabs to shift towards northern bank in zone II & III. A fairly good variety of fishery at the mouth of Thane creek and Ulhas river estuary indicated that timely implementation of mitigation measures may revive the fishery of the two ecosystems.