Studies on the age and growth of Labeo calbasu (Hamilton) with an exploitation pattern from the Ganga River system, Uttar Pradesh (India)

Samples were collected to study the age and growth of Labeo calbasu (Hamilton) from the river Ghaghra (Guptarghat centre, Faizabad). The scales of L. calbasu have been used for age and growth studies in present paper. Study of the marginal rings on the scales of L. calbasu indicates their annual nature. The fish attained growth in 1st 18.7 cm, 2nd 27.8 cm, 3rd 35.7 cm, 4th 41.8 cm, 5th 46.9 cm, 6th 54.9 cm and 7th 57.4 cm years of the life. The growth rate was observed 18.7, 9.1, 7.9, 6.7, 5.1, 8.0 and 2.5 cm for 1st to 7th age classes respectively. The age groups 1+ to 4+ constituted 91.17% of the total exploited population and 8.83% of remaining age groups (5+ to 7+). The maximum exploited population was observed in 2+ age group with 33.68%. Overall exploitation pattern was systematic and a good indicator for heavy recruitment.

China, India, and the Environment

This work was supported by grants from the National Basic Research Program of China (973 Program, 2007CB411600), the National Natural Science Foundation of China (30621092, 30623007), and Bureau of Science and Technology of Yunnan Province.

Development of trawls for medium sized trawlers for Veraval, north-west coast of India

Comparative fishing experiments with 25 m bulged belly and 25 m six seam trawls were carried out to study the relative efficiency of the gear. Bulged belly trawl was found more efficient than the other at depths below 40 m. The tension and horizontal opening were more in bulged belly and six seam trawl respectively. Bulged belly caught more of prawns and lobsters but there was no significant difference in the catch of sciaenids, cephalopods and ribbon fishes in the two nets.

Prospect of fishery, utilisation and culture of crabs in India

Investigations on the fishery, utilization and development of the crabs in Indian waters have been reviewed. Various factors relating to the improvement of fishery, keeping quality of the crab meat and possibilities for an integrated farming of commercially important crabs are discussed.

Standing stock of three species of demersal fishes from southwest coast of India

Standing stock of three principal demersal fishes of the inshore waters off Mangalore was assessed. The assessment was based on fortnightly samplings conducted in an area extending over ca 850 km². The data gathered was computed employing Alverson's methods. The standing stock of Nemipterus japonicus, Saurida tumbil and Grammoplites scaber indicates that this area supports good quantities of these fishes and if properly exploited, will sustain a profitable demersal fishery.

Isolation of Salmonella larochelle for the first time in India

The isolation of a new serotype, S. larochelle (6, 7: eh:1, 2), is reported in this communication. This serotype has not so far been reported from any source in this country. The serotype was isolated on November 27th, 1979 at Bombay from a market sample of frozen frog legs intended for domestic consumption.

India's foreign exchange earners

India's export earnings from fishery products have touched an all-time record of Rs. 33.07 crores in 1969. The most important items which have contributed to this are processed prawn products, frozen lobster tails and frozen frog legs. Even though frogs are not of marine origin, they are processed and exported along with marine products so that for all practical purposes they are reckoned as seafood. Naturally, it is sure to be of absorbing interest to the processors and technological research workers as well as to the general public to know how many varieties/species of these occur in our country and also the localities where they are available. The following is an exhaustive list of the different species of prawns, lobsters and frogs that are found in our country, together with vernacular names wherever available, parts of India where they occur and the largest size (length) to which they grow. The figures in brackets on the left side show the progressive total. The different genera have been arranged in the order of their commercial importance and not according to any scientific principles.

Studies on the occurrence and growth rates of two intertidal fouling bryozoans in the Mattancherry channel of Cochin harbour, south-west coast of India

Occurrence and growth rates of two species of intertidal fouling bryozoans namely Electra bengalensis (Stoliczka) and Electra crustulanta (Pallas) are presented in this paper. The former was a typically marine form, settling on panels only during the high saline conditions of the pre-monsoon period and were absent during the low salinity conditions of the monsoon period, while the latter appeared to be a typical brackish water form settling on panels during the low saline conditions existing during the monsoon and post-monsoon periods and were totally absent during the pre-monsoon months. Regression co-efficient of the former was higher than that of the latter suggesting more pronounced growth in Electra bengalensis. Maximum growth for this species was noticed during March, April and May (pre-monsoon) while for the other species growth was more or less similar during monsoon and post-monsoon months (June-January) showing that the species was at home in oligohaline and mesohaline waters.

Fishing gear in freshwater reservoirs of India

Consequent on the great emphasis given to irrigation, power generation and flood control, several river valley reservoirs have been formed. The fact that these reservoirs support a fairly rich fishery potential needs no special mention. The total reservoir water area in the country is 6.4 lakh h.a. (16 lakh acres) and the yield is 5 to 8 kgm/h. a. in certain reservoirs, rising up to 40 kgm/h.a. in some of the highly productive ones.

Development of trawling in India

Of the three main methods of capturing fish, namely luring, attacking and snaring, the last mentioned has hitherto proved to be relatively more effective and apparently yielded better returns. Trawling falls under this method. The trawl is an economic gear, in terms of investment and yield, even in spite of the fact that the total trawl catches come only second to that of the seines. Commercial trawling in Indian seas is of recent origin and seems to have been initially introduced for the purpose of ground resources survey.

Cathodic protection of the hulls of fishing trawlers in India

Nearly 10,000 mechanised fishing trawlers mostly built of wood and about 100 trawlers built of steel besides a few fiberglass reinforced plastic and a couple of ferro-cement boats constitute the modern fishing fleet of India at present. Metallic corrosion in sea water is a very well-known phenomenon in all ships and various other marine structures; the exact financial loss and the material breakdowns have never been fully realized among the trawler owners in India. The Central Institute of Fisheries Technology at Cochin has been studying these problems for some years and has been able to assess the significance of underwater corrosion particularly of the hull below water line in the trawlers and suitable remedial measures have been suggested in this paper.

Biology of fouling in Neendakara port, a tropical estuary in the south west coast of India

Species composition and some aspects of the biology of the fouling community in Neendakara port (southwest coast of India) has been examined for a period of one year. Fouling organisms were collected with a system of glass panels exposed for varying durations and during different months in the port. One species of sponge, nine species of coelenterates, thirteen species of polyzoans, four species of mud-tube dwelling polychaetes, four species of serpulids, one species each of mud-tube forming amphipod and tanaid, two species of oysters, six species of mussels and not less than eight species of tunicates were the macro fouler which settled over the panels. Monthly and seasonal settlement of the different species has been recorded. Fouling has been a continuous process occurring throughout the year in Neendakara port with slightly fluctuating biomass and considerably varying species composition. Alternate species dominance of marine and brackish water forms has been an important feature of fouling in the area. Number of species of the sedentary fouling animals represented on test panels has been high during the highly saline pre-monsoon period and low during the monsoon period.

Survey on the idle capacity of fish processing (freezing) plants in India - 1. West Coast

The extent of idle capacity in fish processing (freezing) plants estimated by stratified random sampling is reported. The estimates for 1978 and 1979 for the processing plants on the west coast of India were 76.9 % and 73.2 % respectively at the rate of 250 working days per annum and two shifts per day. The percentage error of estimates worked out to 6.04 for 1978 and 6.98 for 1979. Substantial under utilization of processing plants noticed in all the states accounts mainly to the non-availability of raw material (prawn), high cost of production and shortage of power.

Survey on the idle capacity of fish processing (freezing) plants in India - 2. East coast

The extent of idle capacity in the fish processing (freezing) plants in the east coast of India estimated by stratified random sampling and the factors responsible for the same are reported. The estimates of idle capacity of fish processing plants in the east coast for the years 1978 and 1979 were respectively 75.9% and 72.5% on the basis of 250 working days per annum and double shift per day. The percentage errors of estimates worked out to 6.9 for 1978 and 4.7 for 1979. The corresponding figures were worked out on the basis of 200 working days also. Substantial under-utilisation of plants in all the maritime states in the east coast accounted mainly to non-availability of raw material, high cost of production, shortage of power, scarcity of ice and potable water during peak season and frequent labour troubles.