Biodynex : biology, dynamics, exploitation of the small pelagic fishes in the Java Sea

In order to obtain the catch frequency lenght of the species caught by the purse seiners fleet a sampling scheme was set at two main landing places. The present article covers the data collected from December 1991 to December 1993.In the Java Sea, there is a spatial stratification of the fish population, the juveniles staying more inshore than the adults, while the evolution of the average length of the fish caught by the seiners increases from West to East, following a West-East axis. Due to different fishing tactics, the large seiners tend to catch bigger sized-fish than the medium one do. (Résumé d'auteur

Collected reprints on the pelfish communications given to the fourth asian fisheries forum, 16-20 october 1995, Beijing

Since long time ago, the small pelagics are exploited along the north coast of Java Island by two fisheries, one which exploit coastal species, and the other one which exploit mainly the scads (#Decapterus spp.$). Until the seventies, these fish were caught with Danish seines ("Payang") carried by large canoes ("Mayang"). Due to the vessels and the fishing gear used, the fishing season was short and the fishing grounds were located not far from the shore. In 1970's, the introduction of a new net and new type of vessel allowed the extension of the fishing season and of the fishing grounds. The landings show a high seasonality related to the monsoon, phenomenon which seems common to many pelagic fisheries in the Asian region. (Résumé d'auteur

Biodynex : biology, dynamics, exploitation of the small pelagic fishes in the Java Sea

This study is based on the catch and effort data, collected from different sources between 1976 and 1986. The composite model of Caddy and Garcia (1982), one of the models derived from the Schaefer and Fox model, was used to estimate the MSY (Maximum Sustainable Yield) and the optimum effort of the small pelagic resoures in the Java Sea. It seems that the current status of exploitation is near its maximal level. The fisheries exploit a lot of species with various ecological behaviors. Some, such as the coastal specie, are fully and heavily exploited while others, such as the coastal species, are fully and heavily exploited while others, such as the oceanic ones, are partially exploited. Thus it is difficult to give an accurate assessment. Other approaches (analytical models) would allow more precise results. This is why the statistical data collection as well as the biological and behavior study must be continued. Since 1976 the catch of small pelagic increases continuously, in 1985 it reaches 150 000 tons. During this period the CPUE fluctuates a lot. (Résumé d'auteur

Collected reprints on the pelfish communications given to the fourth asian fisheries forum, 16-20 october 1995, Beijing

The small pelagic fisheries in the Java Sea play an important role in fishery development in Indonesia. It is one of the answers to the protein need for the Java numerous population. It represents also a major source of employment and revenue in the coastal communities along the North coast of Java. Through three main flottillas, seining is the main fishing method used and the development of fishing tactics and strategy is still in progress. Consequently the fishing grounds extended to new areas and the landing increased. This paper will describe the evolution of the main parameters of exploitation such as number and power of boats, spatial distribution of effort, total and specific catches as well as the problems of exploitation level and fish quality. (Résumé d'auteur

Sosekima : proceedings of socio-economics, innovation and management of the Java sea pelagic fisheries

The small pelagic fisheries in the Java Sea play an important role in fishery development in Indonesia. It is one of the answers to the protein need for the Java numerous population. It represents also a major source of employment and revenue in the coastal communities along the North coast of Java. Through three main flotillas, seining is the main fishing method used and the development of fishing tactics and strategy is still in progress. Consequently the fishing grounds extended to new areas and the landing increased. This paper will describe the evolution of the main parameters of exploitation such as number and power of boats, spatial distribution of effort, total and specific catches as well as the problems of exploitation level and fish quality. (Résumé d'auteur

Mitochondrial genomic divergence in coelacanths (Latimeria) : slow rate of evolution or recent speciation ?

Dating the divergence between the two known living species of coelacanths has remained a difficult issue because of the very ancient origin of this lineage of fish, which is more closely related to tetrapods than to other fishes. We sequenced the complete mitochondrial genome of a recently captured individual of the Indonesian coelacanth in order to solve this issue. Using an approach based on loglinear models, we studied the molecular divergence between the two species of coelacanths and three other pairs of species, one that has diverged recently (Pan) and two that have diverged more distantly in the past. The loglinear models showed that the divergence between the two species of coelacanths is not significantly different from the two species of Pan. A detailed gene by gene analysis of the patterns of nucleotide and amino acid substitutions between these two pairs of species further supports the similarity of these divergences. On the other hand, a molecular dating analysis suggested a much older origin of the two coelacanth species (between 20 and 30 million years ago). We discuss the potential reasons for this discrepancy. The analysis of new individuals of the Indonesian coelacanth will certainly help to solve this issue