Age and growth of three species of seerfishes Scomberomorus commerson, S. guttatus and S. lineolatus

Length-frequency an:(lysis indicates that the king seer (Scomberomorus cotnmerson) attains a size of 402 mim, 726 mm, 995 mm and 1186 mm total length at 1, 2, 3, and 4 years of age, respectively, the streaked seer (S. Uneolatus) reaches a size of 350 mm, 713 mm, 835 mm and 965 mm total length et 1, 2, 3 and 4 years, respectively, and the spotted seer (S. guttatus a size of 369 mm, 532 mm: and 640 mm at 1, 2, and 3 years, respectively. Back-calculated lengths of fish at the time of ring formation on otoliths figree closely with the results of lengthfrequency analysis. The maximum lengths of king seer, streaked seer and spotted seer met with in the catches are 1936 mm (33 kg), 980' mm (4.6 kg) and 705 mm (2.1 kg), respectively. The theoretical maximum lengths (Lac) computed by Bagenal or Rafail method for the von Bertsfeaffy growth equation are found to be 2081 mm (46.7 kg) for the king seer, 1683 mm (15.7 kg) for the male streaked seer, 1447 ram (24.3 kg) for the female streaked seer and 1278 mm (9.6 kg) for the spotted seer. All the three species develop two rings a year in their otoliths at a regular interval of six months. For all the three species, the exponent in the length-weight relationship is found to be close to 3

Deepsea fishing in Indian waters

The development of Indian marine fIsheries since the early 60s from a traditional, subsistence oriented one into an industrial fisheries was quite substantial. This change got accelerated mainly in the mechanised era of the marine fishery sector. Although with the declaration of the EEZ, an area of 2 million sq. km. came into existence in 1977, there has never been a commercial deepsea fishing worth mentioning. However deepwater trawling conducted by two Mexican trawlers (24 m OAL) imported from the USA in 1972 has paved the way for a humble beginning in the deepsea fishing operations. Gradually by 1982-83 about 11 0 chartered and joint venture deepsea fishing vessels began fishing operations and almost without exception, they exploited mostly the inshore grounds upto 50 m and rarely upto 100 m. But once the depth limitations beyond the 80 m depth line for offshore fIshing operations was enforced in 1983, almost all these chartered vessels left the country

Coastal biodiversity - Conservation and sustainable management

A management regime based on social acceptance, with the power of moral persuasion from within the group of participants, is the only way to manage widely dispersed resources which are sliared by a multitude of small scale fishermen and various other users

The seerfish resources

The seerfishcs are inshore pelagic fishes, distributed mainly in areas within 60 m depth contour. The mean annual seerfish catch of 17,852 t for 1964-81 was accounted for almost equally by the east coast (49.66%) and the west coast (50.34%). While the bulk of the east coast catch came from Tamilnadu (47.91%) tod Andhra Pradesh (40.34%), the States of Kerala (35.48%), Maharashtra (23.44%) and Gujarat (23.14%) contributed the bulk to the west coast. The progressively increasing trend from 1964 to 1981 owes to the increasing number of mechanised gilhietters operating for the larger catch including the seerfishes. (23.44%) and Gujarat (23.14%) contributed the bulk to the west coast. The progressively increasing trend from 1964 to 1981 owes to the increasing number of mechanised gilhietters operating for the larger catch including the seerfishes

Stock assessment implications and management options for the small pelagics in the APFIC region

Problems in stock assessment and management of the exploited fish stocks, especially the pelagic fish stocks, are reviewed. The theoretical and practical constraints in the application of the assessment techniques and production modelling with reference to the small pelalgics are indicated. Appropriate approaches to pelflgic fish stock assessment and management are outlined

Breeding, age and growth of the freshwater shark Wallago attu (Bloch and Schneider) from the Dhir Beel of the Brahmaputra Basin, Assam, India

The Dhir Beel, one of the major live beels of the Brahmaputra Basin, Assam, has an area of 689 ha and situated in Dhubri district of Assam. The dominance of freshwater shark, Wallago attu (8.10%) in the beel is a striking feature. Restricted breeding of W. attu once a year from June to September was observed. The mean observed length was 37.5, 65.0, 84.5 and 99.0 cm in the 6th, 12th, 18th and 24th months of age respectively. The length growth coefficient (K), the asymptotic length (L infinity ), and the arbitrary origin of the growth curve (t omicron ), for W. attu were estimated to be 0.054484 per month, 136.16 cm and 0.0355 month respectively. The calculated life span (T infinity ) of the fish is 123.86 months (about 10 years). The weight growth parameters were estimated where the monthly growth coefficient (K), the asymptotic weight (W infinity) and the arbitrary origin of the growth curve (t omicron) were found to be 0.0743 per month, 7636.92 gram and 0.431908 month respectively. The length-weight relationship follows the cube law

Regional cooperation for managing marine fish stocks in the APFIC region

For effective management of straddling fish stocks, regional cooperation of the participating countries is required. Formation of regional fisheries forums and intergovernmental consultative machinery's is very vital. The functions of the existing regional bodies and the factors which should form the basis for effective management of fish stocks are discussed

Assessment of the Stock of Threadfin Bream (Nemipterus japonicus) in the Northwest Continental Shelf of India

The maximum sustainable yields of N. japonicus and all-demersal fish from the northwest continental shelf are estimated to be 136,975 tons and 1,056246 tons respectively. The standing stock of N. japonicus in the Kamataka shelf is 38,621 tons. which is about 27.7% of the standing stock of all demersal species