240 research outputs found
Artificial spawning by stripping in Dussumieria acuta, a marine pelagic fish and studies on its early development
Artificial spawning was successfully conducted in Dussumieria acuta Valenciennes (Family: Dussumieriidae), a marine pelagic fish, by stripping the fully ripe female and male. The experiment was conducted on board a privately owned shrimp trawler operated in the Palk Bay, by participating in one of its night fishing trips, on 2nd March, 1973. The stripped eggs and milt were mixed in
filtered sea water. Majority of the eggs were fertilized. Detailed microscopic studies were conducted the next day in the laboratory. The first larva hatched out 24 hours after fertilization. The larvae could be reared only upto 48 hours after hatching. The developmental stages of the embryo and the larva are described and discussed. It is suggested that the technique of artificial spawning by stripping and early ranching of the embryos into the sea, if arried out by the fishermen in a variety of commercially
important species which it is possible on board the fishing vessels on a large scale, can increse the natural production
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Carangid resources of India
A review of the research work carried out so far on various
aspects of the carangid resources has been made in this paper based
mainly on the published contributions of Central Marine Fisheries
research Institute. The fluctuations in the fishery since 1950 and
its present status, in the light of the improved tackling devices and
changed fishing patterns, have been analysed. A drastic increase
in the landings was noticed since 1985 which was mainly due to
the mechanization of the country crafts, the use of purse seine and
ringseine, intensification of trawling and the introduction of multiday
fishing. The studies on the food and feeding habits have revealed
that almost all species of carangids are pelagic carnivores, feeding
mainly on a variety of smaller crustaceans and fishes. The stock
assessment studies conducted on certain commercially important
species have shown that most of them are either optimally or
under-exploited and hence there is scope for increasing the production
without adverse effect on the sustainability of the stocks
On the occurrence of the soft-shelled turtle, Pelochelys bibroni (Owen) in marine environment
A soft-shelled turtle, Pelochelys bibroni (Owen), caught alive from Palk
Bay тАФ a new record from the sourther part of lndian peninsula тАФ proves beyond
doubt that the species can tolerate the marine environment, as against the belief
that it is purely a freshwater form. The behaviour of the animal was studied
keeping it under captivity for 14 days
Mixed farming or polyculture
In Kerala, nearly 75-80% of the population consume fish
and their annual per capita consumption rate is about 13 kg.
The rate of fish consumption is likely to go up due to increased
awareness about fish as a source of cheap and highly nutritious
but harmless food item. Hence there is every need to augment
fish production not only to meet our food requirements but also
to increase foreign exchange earnings. The current level of
fish production is inadequate to fulfil all these needs. An
analysis of the trend of fish production during the past few
years indicates that there may not be any significant
improvement in it in the coming years. In this context,
measures to increase fish production are to be thought of
Aquaculture is the only way to achieve this. In Kerala at
present aquaculture is restricted to backwaters and inland
waterbodies. In order to enhance fish production, farming of
fish and other species of aquatic organisms is to be extended
to inshore coastal waters for which suitable farming methods
are to be adopted
The resources of the Indian mackerel - characteristics, exploitation and future prospects
The Indian mackerel contributed to an annual average (1993-'99) catch of 2.17 lakh
tonnes (t). The west coast landed about 80% of its total catch and remaining by the
east coast. The resource is rich in upwelling areas of the west coast with a catch
contribution of 38.68% from Kerala followed by Kamataka and Maharashtra. The
fishery is characterized by annual fluctuations in the catch ranging from 0.14 lakh t
in 1968 to 2.9 lakh t in 1989. The annual fluctuations do not show any pattern;
whereas the decade! trends show a cyclic pattern of ups and downs. The fluctuations
are more pronounced along the upwelling areas of the west coast. In 1990s, there
was a quantum leap in the annual catch chiefly due to the introduction of large seine
nets and motorization of country crafts. The increase was maximum in Kerala,
moderate in Maharashtra and poor in Kamataka. Along the east coast also fishery
showed considerable improvement. Of late, the role of trawl net in the mackerel
fishery is gaining importance. The surface fishery using large seines along the upwelling
areas seems to depend very much on the intensity and duration of upwelling
which is perhaps causing the fluctuations in catch rather than the variations in the
abundance of the resource. The behaviour of the fish to ascend with upwelling and
spreading to deeper waters with sitiking of thermocline seem to control exploitation
and protect the resilience of the stocks. Perhaps the richness of the resource is much
stronger than hitherto believed. With proper management the production can reach
further heights
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The rate of fish consumption is likely to go up due to increased
awareness about fish as a source of cheap and highly nutritious
but harmless food item. Hence there is every need to augment
fish production not only to meet our food requirements but also
to increase foreign exchange earnings. The current level of
fish production is inadequate to fulfil all these needs. An
analysis of the trend of fish production during the past few
years indicates that there may not be any significant
improvement in it in the coming years. In this context,
measures to increase fish production are to be thought of
Aquaculture is the only way to achieve this. In Kerala at
present aquaculture is restricted to backwaters and inland
waterbodies. In order to enhance fish production, farming of
fish and other species of aquatic organisms is to be extended
to inshore coastal waters for which suitable farming methods
are to be adopted
Studies on lantern fish (Benthosema pterotum) 1. Biochemical and microbiological investigation
Lantern-fish, an under-utilised fish is present in abundance, all the year round in tropical and sub-tropical waters. Biochemical and microbiological studies carried out on lantern fish, caught from the Gulfs of Oman and Aden are reported in this paper
The status of carangid fishery at Vizhinjam, Trivandrum coast during 1979-'88
The status of carangid fishery at Vizhinjam during the decade 1979-'88 is evaluated. The details of fishing crafts and gears,catch composition, annual trends are given
On the systematics of rainbow sardines Dussumieria spp. (Family: Dussumieriidae, Pisces) from indian waters
The systematics of the rainbow sardines of the Genus Dussumieria Valenciennes has been studied in
detail. The existence of two species namely Dussumieria acuta Valenciennes and D. hasseltiiJlleeker in Indian
waters has been re-established as against the view of Whitehead (1963) who synonymised these two species
to one namely D. acuta Val. In this study specimens collected from east and west coasts of India were analysed
morphometrically and meristically and the characters compared statistically. Clear differences in many
of the characters, sufficient enough to substantiate the existence of two different species, were noticed. The
two species are redescribed and photographs presented in the text
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