The parameters a and b of the length-weight relationship of the form W=a L super(b) were computed for 46 species caught in a series of demersal trawl hauls over the period 1995-1997 in the Gulf of Salamanca, Colombia.
This Workshop, made possible by a grant from the Asian Development Bank (ADB) to the International Center for Living Aquatic Resources Management (ICLARM), brought together resource researchers and managers to examine the management of coastal fish stocks and existing resource databases in South and Southeast Asia. The results of the Workshop, documented in this volume, highlight the severe problems related to the management of coastal fish stocks throughout the region. All countries recognize that it is time to remedy these problems and that solutions require multiple action.
This article briefly describes the intensive multidisciplinary 3 year research project conducted by the University of the Philippines and ICLARM to document the conditions of the fisheries and fishing communities of San Miguel Bay (Philippines) so that these communities could be integrated into the development planning of the Bicol River Basin Development Project. The research project had three parts, biology, economics and sociology.
Economic analysis of the trawl fishery of Brunei Darussalam was conducted using cost and returns analysis and based on an economic survey of trawlers and B:RUN, a low-level geographic information system. Profitability indicators were generated for the trawl fleet under various economic and operational scenarios. The results show that financial profits are earned by trawlers which operate off Muara, particularly those with high vessel capacity, and that these profits could be further enhanced.
Fishing skill is perceived to play a crucial role in catching fish. The question arises for fishery managers as to whether or not there are observable and measurable attributes of the skipper or vessel that can be monitored and regulated to account for skipper skill and, hence, this source of fishing capacity. Equating technical efficiency with skipper skill, this paper evaluates technical efficiency and skipper skill in the Kedah, Malaysia, trawl fishery to address this issue.
This paper describes some of the analytical options for the application of ecological community analysis to fisherydevelopment. The method of community analysis are useful in determining the boundaries of assemblages of fish, which may be used as the basis for assigning particular parts of the fishery to specific groups of fishers, gear types and harvest pressures. They can also be useful in identifying the effects of environmental change on a fishery community.
The maximum sustainable yield of demersal fishery resources in the Gulf of Thailand to a depth of 50 m is estimated to be 750,000 tonnes. On this basis the Gulf has been overfished since 1973. There were over 4,000 trawlers registered in the Gulf in 1972; over 10,000 in 1982. The total catch of food fish has increased only slightly since 1963, most increases being of trash fish. However, the trash fish component includes increasing numbers of juvenile food fish. Trash fish are now mostly processed into fish meal.
This article describes the refined version of FiRST (version 2004) and provides examples on how the database (‘TrawlBase’) has been used to date for analyses aimed at establishing historic resource baselines and examining the status of coastal fishery resources. The results show a severe decline of resource biomass to an average of 22% of pre-exploitation levels, with cases as low <4%. These results clearly demonstrate the strong impact of fishing on coastal resource biomass and diversity.
Demersal trawl surveys have been used for assessments of fisheries potential and monitoring the status of fish stocks in many countries in South and Southeast Asia. This paper presents the development of a database system, the “Fisheries Resource Information System and Tools” (FiRST), from a regional collaborative effort between eight countries and the WorldFish Center. The effort has collated about 21 000 hauls/stations from research trawl surveys across the South and Southeast Asian region. FiRST (ver.
The species list is drawn from an analysis of catches taken by Sumalian and Russian trawlers in the Gulf of Aden and the Arabian Sea between 1985 and 1990. The southern coastline of the Republic of Yemen has been divided into 7 areas, including waters around Socotra Island. The average depth of each trawl was recorded in 50 m increments. Non-appearance of the species in the area does not mean that the species do not occur in that area or depth, merely that it was not recorded in any of the samples analyzed. Specimens that could not be identified to species level have been excluded.