Indian Tuna Resources: Distribution, Commercial Exploitation, Utilization and Trade

Tuna and tuna-like fishes are important both from global demand and economic view points. They include 40 species occurring in the Atlantic, Indo-Pacific Oceans and in the Mediterranean Sea. Archaeological evidence showed that, tunas being harvested by early Europeans in the area around Sweden, by Native Americans near British Columbia and by the peoples of the Joman culture near Japan. However, industrial fishing for tunas began in the 1950’s and global production has tended to increase continuously from 0.6 million tons in 1950 to over 6 million tons in 2008. Catch of principal market tuna species was estimated as four million tons in 2008, which represented about 67 per cent of the total catch of all tuna and tuna-like fishes. Most of these catches were taken from the Pacific Ocean (70.2 per cent), with the Indian Ocean contributing 20.4 per cent with an estimated catch of 870,000 tonnes and the rest by Atlantic Ocean and the Mediterranean Sea (9.5 per cent). Major contributors to the global tuna production are skipjack tuna (57.5 per cent), followed by yellowfin tuna (27.1 per cent), bigeye tuna (9.6 per cent), albacore tuna (4.7 per cent) and the rest (10.7 per cent) by other species. According to assessments carried out during 2010 by ICCAT, IOTC, IATTC and WCPFC the international organizations responsible for management of the tuna stocks of in the world Oceans, many tuna stocks are heavily exploited, some unsustainably, and the catches in many cases are declining

Age determination in fishes

Fisheries management relies on the proper understanding the fish population dynamic. It includes determining the biological parameters, including size at maturity, duration of spawning season, mortality estimates, age and growth. Accurate information on age of fish is an important pre-requisite for extracting precise information on growth, mortality, recruitment and other fundamental population parameters of fishes for stock assessment. The outcome of conventional age estimates using length frequency data depends upon the sample quality, selectivity of the fishing gear etc. The stock assessment results may therefore be affected and sometimes give results which is having no bearing on reality. The hard parts of the fishes also grow with the fish and the growth process may left some inscription on such parts and if that can be interpreted properly, will get precise idea on growth. These inscriptions may result from either changes in the environment which the fish inhabits, or food availability, or physiological states of the fish. However, free swimming fishes always lives in ideal conditions and do not leave any environment related markings in their skeletal structures. So interpretation of hard part inscriptions need utmost care

Common Pelagic Finfish Families and their Identification

Bony fishes are distinguished by the presence of bony endoskeleton. Their second noteworthy character is the presence of a swim bladder or lungs, which helps the fish to maintain its body density equivalent to that of its surrounding medium. The skin of bony fish is normally covered with overlapping scale, which are either cycloid or ctenoid. In some it become obsolete and in others it is modified by calcification to an ossified dermal covering in complete bony coating

Peningkatan Hasil Belajar dalam Pembelajaran Ilmu Pengetahuan Alam Menggunakan Media Realia Kelas IV

Improved Learning Outcomes , In Natural Sciences Learning Using realia Media Elementary School Fourth Grade 14 Bengkayang. This study aims to improve learning outcomes of students in the fourth grade Elementary School 14 Bengkayang using realiaMedia . The method used is descriptive method to form a Class Action researchs. research . Descriptive method is a method that seeks to describe, and interpret the object under study in accordance with the Thereal . While the form of action research as part of efforts to understand and solve problems scientifically , systematically and logically . From the initial test results obtained in Cycle I mean classes that only reaches 45.3 or just 33 % were completed and in Cycle II increased to 70.6 or 100 % were completed . This means that learning to use realia media can increase student learning outcomes Elementary School fourth grade 14 Bengkayan

Emigration dynamics of three species of penaeid prawn from backwaters and tidal ponds of Cochin, India

Emigration of three species of penaeid prawn from backwaters and tidal ponds were studied. Considerable diel, tidal, lunar and seasonal fluctuations were observed in emigration process, which was almost nocturnal. Rate of emigration and composition of emigrants varied with time of migration

Pelagic fin fishery resources of India

India is endowed with a long coastline of 8129 km. Being tropical country, the marine ecosystem bordering Indian sub-continent contain large number of species adapted to wide range of habitats, from mangrove swamps, estuaries, saline lagoons, sea grass meadows, sandy/ muddy/rocky coasts, coral reefs, oceanic islands to deep oceanic realms. Theses resources are supporting the marine fishery of the country. The water spread of continental shelf is 0.5 million sq. km and of EEZ is 2.02 million sq. km. The annual catchable marine fishery potential of the EEZ is 4.42 million tonnes. India is one of the leading nation of the world in marine fish production and export

Peningkatan Aktivitas Pembelajaran IPA dengan Menggunakan Metode Eksperimen di Mis

The problem in this study is science learning How to use experimental methods to increase the activity of students in class V Mis - Righteous Ketapang Ash ? " . means of collecting data and interviewing techniques initial observations of classroom action research . The method used is descriptive nature of the research is a collaboration by following the action research procedures , including planning , implementation , observation , and reflection . Research subject is a class V student Mis - Righteous Ash Ketapang District , amounting to 24 people in the second semester of the school year 2013/2014 and Mis Ash - Righteous teachers as teacher collaboration . This research was conducted by 2 cycles . The results obtained by the research that has been done on improving science learning activities using an experimental method in Class V student Mis - Righteous Ash as follows . With the use of experimental methods to increase the physical activity of the first cycle was 70 % and cycle 2 was 89 % . With the use of experimental methods to increase mental activity first cycle was 35 % and cycle 2 was 58 % with the use of experimental methods , can increase the emotional activity of the first cycle was 73 % and cycle 2 was 88