The Prawn fishery of the South Kanara coast with emphasis on the unusual catches of Metapenaeus dobsoni by purse seines and trawls during the first half of September, 1983

The commencement of the 1983-'84 fishing season witnessed bumper catches of prawns (Metapenaeus dobsoni), particularly in purse seines, breaking all previous records. The unprecedented catch of prawns in purse seines might possibly be due to the fact that the resource of M.dobsoni was found to be very close to the shore. Moreover, the behavioural pattern of females to come off the bottom for spawning and remain in the column waters for considerable amount of time as they were fully exhausted. The huge size of the purse seine nets helped to encircle large areas and fish the 'accumulated stock' resulted out of the closed season (June-August) due to monsoon might have helped the mechanised fishery, particularly purse seiners, to exploit them heavily. Although there has been wide fluctuations in the catch of M. dobsoni in September, during various seasons, the present studies indicated that the intensive fishing during September may not lead to any conservatory problems. These prawns have already reached their maximum size (prawns larger than the presently reported ones have not been recorded any time in the fishery) and hence in the fag end of their life

Squilla (Mantis shrimp) fishery of Karnataka state

The stomatopod squilla, locally known as 'pucha' or 'puchi' (Malayalam: Che///), are marine crustaceans, caught In varying quantities exclusively by shrimp trawlers operating up to 50 m depth all along the east and west coasts of India. Owing to the presence of large number of spines on the body and the low flesh content, it is not being eaten at present in our country. However, it is in considerable demand since it is a good raw material for converting into fishmeal, poultry feed and manure

Marine crab fisheries of Karnataka State- a retrospect

Marine crabs form 0.47 % of the marine fish production and 2.1 % of the trawl landings in Karnataka State. The annual average crab production of the State during 1983-1993 was to the tune of 1179 tonnes which forms about 5.1 % of the annual average marine crab production of our country for the same period

Food and feeding of Portunus (Portunus) sanguinolentus (Herbst) and Portunus (Portunus) pelagicus (Linnaeus) (Brachyura: Portunidae) along Karnataka coast

The diet of Portunus (Portunus) sanguinolentus and P.(P.) pelagicus Jmlin1y consisted of crustacean Fishes, molluscs, large quantity of unidentified matter and debris. Quantitative analysis of the gut contents revealed that crustaceans contributed to 47.1% and 42.6 %, fish remains 29.0 % and 20.4 %. molluscs 5.7% and 20.0 % detritus 4.9 % and 4.7 % respectively of the gut content by volume in both species respectively. The study indicated that these crabs are primarily predators of sessile and slow moving benthic macro invertebrates

Length-weight relationship in two marine portunid crabs, Portunus (Portunus) sanguinolentus (Herbst) and Portunus (Portunus) pelagicus (Linnaeus) from the Karnataka coast

Portunus (Portunus) sanguinolentus and P.(P.) Pelagicus support fishery of considerable value all along the Indian coast and together contribute up to 96 % of the crab landings. In the context of increased importance of crab resources and interest eltinced in culture, there is an urgent need to study tlie biology and related aspects

Spawning biology of two marine portunid crabs, Portunus (Portunus) sanguinolentus (Herbst) and Portunus (Portunus) pelagicus (Linnaeus) from the Karnataka Coast

Weekly samples of P (P) sallguilloienllls and P (P) pelagicus caught by di !ferent type of gears were taken from Mangalore, Malpe and Karwar - three important fish landing centres in Kamataka during 1992-94 and analysed for carapace width, weight, sex and maturity conditions. For describing the gross maturity stages of ovary, the following stages were recognised. I) immature virgins, 2) immature resting 3) early maturing, 4) late maturing, 5) mature and 6) spent

Potential new resources of penaeid prawns of the Mangalore coast

Penaeid prawns belonging to the genera Parapenaeopsis, Penaeus and Metapenaeus of the family Penaeidae exploited by mechanised trawlers support a fishery of considerable magnitude along the Mangalore coast. Among the penaeid prawns exploited Metapenaeus dobsoni, M. Monoceros, M. qffinis, Parapenaeopsis stylifera, Penaeus indicus and P. monodon are important and contribute upto 90-99 % of the prawn catch along this coas

Study on the fishery and biology of the mantis shrimp Oratosquilla nepa (latreille) of south kanara coast during 1979-83

The catches of Oratosquilla nepa along the South Kanara coast were maximum during 1981-82, amounting to 2543.3 t at a catch rate of 16.5 kg|h at Mangalore and to 1868.8 t at 16.7 kg|h at Malpe. The catch was high during January- April. A mean growth of 7-8 mm|month was indicated. The species appear to grow to it length of about 108 mm by the end of first year and to live for 15-16 months. In the development of the ovary, five maturity stages, ie., immature, early maturing, late maturing, mature and spent|spent-recovering, have been recognised. The size at maturity at 50% level is estimated at 95 mm. The spawning season is found to be extending from December to October with peaks during March-June and September-October. Females generally outnumbered males. Chi-square test showed significant variation from 1:1 ratio in the distribution of sexes. The fecundity is estimated at 6,78,200 in a female measuring 108 mm body length. The growth parameters, 1 a, and c.k were estimated at 143 mm and 0.2877 respectively. The mean.monthly Z values were 0.9767 for males and 0.923d for females