cifri annual report 2007- 2008 - Central Institute of Brackishwater ...

Reservoir Fisheries
The improvement ofreservoir fish production isan
important thrust area ofthe Institute. In this direction
casestudiesindifferent statesare being worked out for
developing site specific protocols. Accordingly,
Suvarnavathy reservoir in Karnataka was investigated
in which the total catch was 39.5 t and Indian major
carps contributed a high of 95% to the total catches
followed by tilapia. The mean CPUE was 12.3 kg
registering per unit fish yield of 80.6 kgiha. Interim
recommendations for enhancing productivity of
Suvarnavathy reservoir have been formulated for
implementation by the StateFisheriesDepanment.
Another issue of concern for reservoirs is
developing a model for appropriate management. In
this direction secondary data on reservoirs (which
include mo~hometric details, fish catch statistics,
yield potential, primary production, etc.) collected
from different states (viz. Karnataka, Rajasthan.
Maharashtra, Tamil Nadu. Uttar Pradesh. Haryana,
Kerala. Himachal Pradesh, Andhra Pradesh. Orissa,
Madhya Pradesh and Punjab) were conlpiled and
analysed for development of sofiuare models.
Preliminary analysis of data carried our to assess any
relation of fish yield with area, mean depth and
primary production and other critical parameters.The
relationships worked out indicated a high coefficient
of determination (R') forthe relationships Mew Deplh
vs ~eld(R'=0.889)andAreuvsCalcl(R*=O.715).
Estuarine Fisheries
The country has significant resource of estuarine
ecosystems. In this context, a backwater lake was reassessed
for its ecological status and fishery.
Accordingly. physico-chemical profile, soil quality
and texture, primary production and biotic production
were extensively studied in Pulicat lake. The fisher~es
of Pulicat largely depend on the catch of P indirus.
mullets (M cephalus > M lade > M canneolus > .U.
macrolepis > Lira puruiu) and Cliaitm chairos The
dominant fishery of 1970s and 1980s. the Chonos
chanos has, however, become almost rare. Similar has
been the abundance of P ,nonodon, the tiger prawn
which was predominant during 1970s & 1980s The
average catch per fisher per day has been estimated to
bepoorat300gtoS00g1day,mainiy of P inri'icu.\
While working in the Godabari estuarine s)stenl a
total of 68 species of fishes, beloii~iiig to 37 fnm~lirs
and I2 Ordcrsl~ave been recorded.
Tliecontribution ofuetlandr to open water inland
production itsignificant and the lnst~tutr is inviil\ed
in improving their fish yield. In this context. uutiund
programme is executcd in differe~lt h1nd9 nl'
ecosystems. Accordir~ply, during this period fish catell
and yield as well as environmental parAmeters ii-urn
seven wetlands, situated at 24 Parganas Nonli dislricr.
Nadia distria and at Hooghly district of West Bengai
were studied. The yield of natural fish stocks tioni
thcsc wetlands varied from 139 to 609kg:ha. The catch
composition showed that Punrrur spp. as a group
forms a major contributor to the total catch nf these
wetiands (6-20%). followed by Cilanrro spp. (7-18%)
and prawns(5-12%).
A total of 76 species among 55 genera and 30
fanlilies uere recorded from beeO of West Bengal.
Exotic fish species vrz. Barbon,vrnus pa~lio~rorui
(Punliur po~~ioiiohrs) Pongasianodon Ii,vpophrhobnur
(Pangasius sulchi). Clarras gariepinnur.