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PADDY-CUM-FISH CULTURE [Vol. XXIII, Part IV,
23 September 1951. The paddy seedlings were 24 in. high and 6 in. apart at
the time of fish release. Daily record of water temperature in the paddy field
was kept. The water temperature ranged from 23.3ºC to 24.4ºC.
The experiment lasted 66 days. At the conclusion of the experiment on 28-11-
1951, 127 fish were collected. They measured on an average 5.24 in. and weighed
28.3 gm. each. Due to inaccessibility, it was not possible to take monthly record-
ings of length and weight of the fish.
The water in the plot was fertile and teeming with fish food; this no doubt
was due to preliminary manuring of the paddy field. Consequently the fish recorded
a good rate of growth showing an increase in length of 3.29 in. and a gain in weight
of 27.23 gm. The rate of growth for the same species in this experiment in 66 days
as compared to the gain in length of 1.37 in. and a gain in weight of 8.98 gm. in
122 days in Experiment No. I is noteworthy. Manuring of the paddy plots prior
to fish release is very beneficial for fish growth. The total production of fish per
acre in this experiment as computed was 114.2 lb.
At the Visweswaraya Canal Farm, experiment of paddy yield in the fish culture
lot was 147 seers while in the control lot, it was 130 seers which showed an increase
of 13 per cent in paddy yield.
Out of 1,100 fish introduced, there was a survival of only 11.5 per cent. The
fingerlings had grown to such a size that they were able to jump out of the paddy-
cum-fish culture lot into the adjoining fields during night time. Predation due
to the presence of crabs and water snakes was also observed.*
SUMMARY
1. Culture of Ophicephalus striatus in paddy field requires better facilities like
raising the height of the bund and use of manure in preparing the paddy plots.
2. It is possible to produce 100 lb. of fish in an acre of paddy field and at the
same time increase the yield of paddy by 7 per cent to 13 per cent.
3. The paddy fields could be used as nurseries in the culture of murrels.
ACKNOWLEDGMENT
The experiments were started at the instance of Sir Datar Singh, Additional
Secretary, Ministry of Food and Agriculture, Government of India, during his visit
to Hessaraghatta grass farm.
*The relatively poor results obtained in these experiments can be ascribed to the
defective selection of fish for culture. The murrel is a carnivorous fish and often shows
cannabilistic tendencies, if live food is not available in its environment. The paddy field, in
which they were cultured, at least in the first experiment was, of the desmid-type. It is likely
that faunal elements, which from the food of murrel, were not available in adequate quantities
in the area and the stronger specimens may have devoured the weaker ones. Further, being
an airbreathing fish, the murrel can travel over long distances on wet land and it is not quite
suited for culture in paddy fields having low embankments. The high rate of escapement seems
to have been the main reason for low production. Instead of the murrel, if any of the carps
had been employed for the experiments, a much better yield could have been obtained.
A production of 150-300 lb., estimated by me in 1949, is under natural conditions and not
under intensive fish culture. The value of the above experiments chiefly lies in the fact that
when fish are cultured in paddy fields, there is an appreciable increase in the yield of the
paddy. (Dr S. L. Hora)