The prawns and shrimps of India belong to three major families, namely Pedaeidae, Palaemonidae and Sergestidae of the decapod groups. A few deep-water forms belonging to the family Pandalidae are also gaining commercial importance with the result of recent exploratory fishing activities. There has been much confusion in the usage of the terms prawns and shrimps. At the Prawn Symposium of the I.P.F.C held at Tokyo in 1995, it was decided that the term prawn should be applied in Penaeids, Pandalids and Palaemonids, while the use of the term shrimp should be restricted to the smaller forms of economic importance here are to be termed as prawns.
The prawn production in India form about 15% of the total world production of prawn and shrimps. If the substantial production from back waters, paddy fields lakes and estuaries etc. are taken into account, the percentage of Indian production to the would production of marine prawns will be about 20%.
The production of marine crustaceans in India with its composition forms three broad groups. The penaeid prawns form about 56% of the average annual crustacean production in India. The next group in importance is the non-penaeid prawns forming about 40% of the average annual production of crustacea. The balance of 4% consists of other crustaceans.
Crustaceans are landed in all the maritime States of India, but the amount of landings very from State to State. The landings of East Coast of India form only about 17% of the total crustacean landings, while the balance of about 83% is landed on the West Coast of India. Among the States, Maharashtra ranks first by contributing about 48% of the total crustacean landings in India followed by Kerala which contributes on an average 28% of the average annual production of crustaceans. In fact, the major crustacean fishery of India are today located in the two States, Maharashtra and Kerala.
Distribution of Penaeid prawns
The penaeid prawns include three genus Penaeus Metapenaeus and Parapenaeopsis.
The genus Penaeus has a worldwide distribution and the various species belonging to it are found both in tropical and temperate latitudes. Practically all of them are marine although some are know to spend a part of their life in the brackish water and even in freshwater. Of the 28 valid species of the genus, only 8 are represented in Indian waters: they being Penaeus japonicus, P. latisulcatus, P. canaliculature, P. monodon, P.semisulcatus, P. inducus, P. merguiensis and P. penicillatus.
Most of the species belonging to this genus grow to a large size and they support commercial fisheries in many productions of prawns and shrimps. All the eight species recorded from India are listed as prawns of economic value, although, some of them do not occur in commercial quantities in India.
Penaeus indicus in India supports commercial fisheries in both marine and estuarine environments on the east and west coasts.
In India P.semisulcatus is caught along with other prawns only occasionally. It is not known to contribute any significant proportion of the marine catch. However, the species is often well reported in the brackish water fishery of the west coast of India.
P. monodon, the largest of marine prawns is known as "Jumbo tiger prawn" in most of the countries of Indo-Pacific region. The species is widely distributed in east and west coast of India and Sri Lanka. The species apparently prefers warm water habitats. It is recorded from seas, rivers, estuaries, brackish waters and even from freshwaters.
Species belonging to the genus Metapenaeus are distributed throughout the Indo-Pacific regions. Of this genus, Metapenaeus, comprising of 24 species, only 10 species have been recorded to occur in Indian waters. They are M.dobsoni. M. monoceros, M.affinis, M. brevicornis, M. ensis, M. lysianassa, M. burdenroadi, M. stebbengi, M. kutchensis and M. alcocki.
Metapenaeus dobsoni is distributed from Indian waters through Malaysia and Indonesia to Philippine islands. It is found in brackish water as well as marine environments. In Indian waters the species is present in the juvenile stages in most of the estuaries and brackish waters along the coast line and the adults in inshore areas upto 20 fathoms depth along the south west coast of India, where it contribute to a major fishery.
Metapenaeus monoceros is distributed in South Africa, Mediterranean and Indian seas to Malaysia with the eastern limit a Malacca strait. Although it is a marine species, it is found in marine, brackishwater and freshwater environments.
In Indian waters, it occurs in the Juvenile stages in most of the estuaries and back waters with muddy bottom along the coast line and adults in the sea upto 50-60 meters depth both muddy as well as sand and silt bottom.
The general distribution of Metapenaeus affinis in Indian seas through Malaysia and part of Indonesia to Hong Kong and Japan in marine and brackish water.
In Indian waters, the juveniles of the species are found in very small numbers in the backwaters and estuaries and adults occur in the inshore waters to a depth of about 45 metres.
The general distribution of Metapenaeus brevicornis is Pakistan through Indian, Malayesians, Thailand and Indonesian waters to about East Borneo.
In the distribution of this species in Indian waters one difference noticed from other species like M. monoceros and M.affinis is that, it does not occur in the southern area, but contribute a good fishery in the northern region both on the west as well as east coasts. Well represented in estuaries and inshore waters especially in the east coast. In the Gulf of Kutch area the species is mostly distributed in areas with sandy bottom.
The genus Parapenaeopsis comprising of 16 species enjoys a wide distribution. Majority of the species are restricted to tropical and warm temperate shallow seas, but few of them are also recorded from brackish water regions. Most of the species are recorded from Indian region so far. They are Parapenaeopsis uncta, P. cornntra maxillipedo, P. nana, P. acclivirostris, P. sculptilis, P. hardwickii and P. stylifera. Among them, P. stylifera, P. sculptilis and P. hardwikii are commercially exploited in India.
Unlike are most abundant from Veraval to Trivandrum coast, but moderately available in the Sind Mekran and Kutch areas. In the southern most part of west coast and in east coast they are found in lesser numbers. It occurs all the year round in the west coast in India, but abounds the shallow inshore waters from January to June and deeper waters in September to October. Their occurrence in the marine regions and the relative abundance during warmer months seems to be due to their inability to tolerate lesser salinity.
Parapenaeopsis sculptilis is widely distributed tropical specials found from west and east coast of India to Hong Kong through Malayesian waters and Indonesia to tropical Australia and New Guinea.
In India, commercial exploitation of the species is done at Kutch, Bombay in west coast and Hoogly estuarine system in the east coast. It is also reported from the Godavari river system through out the year.
Parapenaeopsosis hardwickii ranks third among the commercially exploited species of the genus Parapenaeopsis in the Indian region. The general distribution of the species is from the coasts of India through Malayesia to southern China. Although, the species occur on both the coasts of India, it support a good fishery only in Bombay and in lesser magnitude in Andhra coast.
The species is subjected to commercial exploitation at different stages of life from both estuarine and marine environments. The brood prawns, which come into backwater in November December reaches a size of 110 mm. In September-October of the following year, when they move out into the sea. The entire backwater fishery, therefore, are constituted by 0 year class prawns. Three-year classes (0,1 & 2) of this species are represented in the trawl fishery.
In the backwater of Kerala, the species is fished almost through out the year. The marine fishery is largely seasonal. On the west coast, the season generally coincides with the monsoon period, June-September, but the fishing season of the species in December-February have been observed both in east and west coast of India.
The estuarine and backwater fishery for the juveniles of the species is carried out in very shallow waters not exceeding 10 metres in depth. But the commercial fishery for adults are generally carried out in coastal waters upto a depth of 50 metres along Indian coast.
The juveniles of the species have been observed to spend their life from late August to middle of October in areas of the sea, where Zostera marina are growing. After middle of October, the species seems to be fished only from the off shore areas, where the bottom is muddy. In the marine catches, the size composition varies from 150-180 mm., the largest recorded size being 222 mm.
The species also form a significant portion of prawn catches of Bheris of West Bengal, where they attain a length of 76-127 mm. at the end of the season.
Like P. indicus, this species is also subjected to commercial exploitation at different stages of life from both estuarine and marine environments. The entire backwater fishery constituted by 0 year class. The species occurring in the trawl catches from both the coasts of India come under late 0-year to early 1-year class.
Specimens over 300 mm. in total length are common in the trawer catches landed from relatively deeper waters of the west coast.
In Kerala backwater fishery, the species is caught through out the season in small numbers. In Bombay, they are found in commercial from August-October.
The contribution of the species in the overall prawn fishery of the country is roughly estimated as 0.9%.
The fishery in backwater environments is constituted by the 0 year and 1 year classes by marine fishery.
During the monsoon months, when the mud banks occur, in various places along the coast, shoals of these prawns approach the shore in these areas, so close as to make it possible for fishermen to use for catching them.
The population of the backwater and estuaries sizes ranging from 30-70 mm in the catches, the marine fishery size range from about 60-125 mm.
Juveniles are fished in backwaters, estuaries and paddy fields in shallow areas ranging from 1-15 meter depth. Young adults and adults are caught from sea in depths up to 25-30 metres.
In marine inshore areas, the fishery is largely seasonal fron June to September. The off shore fishery extends from November to June. In brackish waters of Kerala, the fishery extends from middle of November to April.
Only 0 year class contributes to the backwater fishery of Cochin. In the trawl catches, 3-year classes have been recorded. The bigger year class enters the fishery in November-December and the smaller size appears later. It is noticed that in some years, the bigger classes fail to appear in the fishery.
The backwater fishery constitutes 56-90 mm. the inshore fishery constitutes of the species of 40-120 mm., mostly juveniles. The adults are caught in the trawl fishery the size range being 90-175 mm. The maximum size attained is 180mm. in the deeper waters (50-60 metres).
The species are abundant in backwaters from March-June and in November. The season in the trawl fishery is November-December. In Bombay waters, the fishery commences during the rainy season, July-August. In Chilka Lake it is abundant in November-June.
In the backwater fishery only 0year class (30-120 mm.) is represented. The inshore and off shore fishery is mostly represented by I and II year class (71-130 mm.) In the trawl fishery, the II year class generally enters the fishery in earlier half of the season and the I year in the later half (121-140mm.)
In the backwater fishery, the species is abundant from January-June. The peak season for the species in the trawl fishery is from December-February in Cochin, January-March in Bombay and January-August in Calicut. The inshore fishery of the Kerala coast intensifies after the formation of mud banks (annual) on which the prawn concentrates.
In Hooghly estuary I and II year groups of the species form the fishery. 0 and III year groups also contribute to the fishery. In the Hooghly estuary, the catches ranged in size between 15 and 115 mm. the inshore fishery for the species range from 40-110 mm. in length. They occur in shallow waters ranging 4-7 meters depth.
The species is found through out the year, the peak season is form January-March in Bombay coast, July-February in Gulf Kutch area. In Hoogly estuaries it is fished through out the year with bulk landings in November-February.
In the inshore waters, the species is abundant upto 22 metres especially from the depth ranges of 12-20 meters. The population is composed of 0,1 and II year classes, having a size range from 10-145mm.
At Veraval, the species support a good fishery during October-December period. In Bombay coast they are caught through out the year. At Karwar, the species ranked second in the prawn catches landed by the trawlers. The peak season is from January-April in Mangalore, December-February at Cannarore and February-may in Malabar coast.
Although the species occurs all the year round in the west coast of India, it abounds the inshore waters from November-December to May-June and offshore waters in September-October.
Smaller individuals belonging to 0-1 year class contribute to the fishery of less saline areas and the larger sizes (I & II years class) support the inshore fishery.
In the Gulf of Kutch area, the species contribute about 19% of the total prawn catch during September-January period. In Bombay coast, the species occur throughout the year, but available in commercial quantities from October-may with peaks in December-February. In the Hoogly estuary, the species is dominant in sinter and monsoon months. The species is mainly confined to the fringes of the coast out to the four-fathom contour. But it may be found as deep as 7 fathoms. In India the inshore fishing seasons extend from October to May and the river systems during monsoon.
The species forms about 0.6% of the annual prawn landings of India. In Bombay coast, the species form 3.7% of the total prawn catch, and the fishery starts in November and continues upto may, the peak season being November and January. The size ranges between 55-65 mm. in case of males and 80-100 mm. in case of females.
In the backwaters the prawn is caught in large quantities in stake nets, cast nets, drag nets, dip nets and small scoop nets. In inshore marine fishery the principal types of gear employed in the capture of prawns are boat seines and shore seines; from the deeper regions prawns are caught in trawls which prawn is caught in Hoogly estuaries. Besides small drag nets, dip nets, barrier nets, behundijal are also used for capture of prawn. Along Bombay coasts, dol net are the main gear for catching prawn. In Chilka Lake traps are extensively used for catching prawns.
Small dug outs canoes (4-6 meters long) are the principal craft in use in the backwaters. Larger dug out (6-10 meters). Canoes and catamarans are used in inshore fishery in the West Coast of India. On the East Coast plank built canoes and catamarans are in use. The shrimp trawls are operated from 7-11 metres pablo type wooden boats powered with 10-30 H.P diesel engines. A few large boats are also operating shrimp trawls.
With the increasing potentialities of export of prawns to the world market, a major portion of the prawn production of our country is being processed, mainly for freezing and the frozen products sent to U.S.A. and Japan. Only tiny prawns, which do not find export market, are consumed internally.