Farm-raised shrimp: good aquacultural practices for product quality and safety

(PDF has 75 pages)

Seafood safety: economics of Hazard Analysis and Critical Control Point (HACCP) programmes

Seventy percent of the world's catch of fish and fishery products is consumed as food. Fish and shellfish products represent 15.6 percent of animal protein supply and 5.6 percent of total protein supply on a worldwide basis. Developing countries account for almost 50 percent of global fish exports. Seafood-borne disease or illness outbreaks affect consumers both physically and financially, and create regulatory problems for both importing and exporting countries. Seafood safety as a commodity cannot be purchased in the marketplace and government intervenes to regulate the safety and quality of seafood. Theoretical issues and data limitations create problems in estimating what consumers will pay for seafood safety and quality. The costs and benefits of seafood safety must be considered at all levels, including the fishers, fish farmers, input suppliers to fishing, processing and trade, seafood processors, seafood distributors, consumers and government. Hazard Analysis Critical Control Point (HACCP) programmes are being implemented on a worldwide basis for seafood. Studies have been completed to estimate the cost of HACCP in various shrimp, fish and shellfish plants in the United States, and are underway for some seafood plants in the United Kingdom, Canada and Africa. Major developments within the last two decades have created a set of complex trading situations for seafood. Current events indicate that seafood safety and quality can be used as non-tariff barriers to free trade. Research priorities necessary to estimate the economic value and impacts of achieving safer seafood are outlined at the consumer, seafood production and processing, trade and government levels. An extensive list of references on the economics of seafood safety and quality is presented. (PDF contains 56 pages; captured from html.)

Guidelines for reducing porpoise mortality in tuna purse seining

More than a decade has passed since the passage of the Marine Mammal Protection Act of 1972. During that time the U.S. tuna purse seine neet reduced its incidental porpoise mortality rate more than 10-fold. This was made possible through the development of gear and techniques aimed at reducing the frequency of many low probability events that contribute to the kill. Porpoise are killed by becoming entangled or entrapped in folds and canopies of the net and suffocating. The configuration of the net, both before and during the backdown release procedure, is a major determinant of the number of porpoise killed. Speedboats can be used to tow on the corkllne to prevent net collapse and also to adjust the net configuration to reduce net canopies prior to backdown. Deepening a net can reduce the probability of porpoise being killed by prebackdown net collapse. The effects of environmental conditions and mechanical failures on net configuration can result in high porpoise mortality unless mitigated by skilled vessel maneuvers or prevented by the timely use of speedboats to adjust the net. The backdown procedure is the only means to effectively release captured porpoise from a purse seine. It is also the time during the set when most of the mortality occurs. The use of small mesh safety panels and aprons in the backdown areas of nets reduces porpoise entanglement, and Increases the probability of an effective release. The tie-down points on the net for preparing the backdown channel must be properly located in order to optimize porpoise release. A formula uses the stretched depth of the net to calculate one of these points, making it a simple matter to locate the other. Understanding the dynamics of the backdown procedure permits a thorough troubleshooting of performance, thus preventing the repetition of poorly executed backdowns and thereby reducing mortality. Porpoise that cannot be released must be rescued by hand. A rescuer in a rigidly inflated raft can rescue porpoise effectively at any time during a net set. Hand rescue can make the difference between above average kill and zero kill sets. In all circumstances, the skill and motivation of the captain and his crew are the final determinants in the prevention of incidental porpoise mortality in tuna seining. (PDF file contains 22 pages.)

Comparative study on the catch efficiency and size selection of entangling nets in Lake Kainji, Nigeria

The relative catch performance and selectively of gillnets and trammel nets were investigated in 12 sampling stations in Lake Kainji, Nigeria. 3 types of nets with dimensions 50mx3m were constructed using 76mm and 178mm meshsizes for two gillnets, 76mm and 178mm meshsizes for the lint and ar mour nets of the trammelnets respectively. All the nets were randomly ganged together to form a fleet of nine nets each, and were set twice in each of the 12 stations which gave a total of 24 fishing operations. A total of 365 fish weighing 88.9kg and belonging to 16 different species were caught in all the nets. The trammelnet had the highest catch by number and weight constituting 60% and 69.22% of the total catch and weight respectively with a relative species Diversity Index of 0.82. This was followed by 76mm gillnet which constituted 38.63% by number, 28.09% by weight, 0.69 relative Species Diversity Index. The 178mm gillnet had the least catch of 1.37% and 2.9% by number and weight respectively with 0.25 relative Species Diversity Index. There was significant difference (P<0.05) in the number and weight of fish caught in the different nets. The minimum selection length for these species caught were the same for each net. The trammel net had a wider selection range that skewed to the right, a higher modal and median length indicating larger individual species being entangled in the net

Advantages of using crest nets to sample presettlement larvae of reef fishes in the Caribbean Sea

Identifying the spatial and temporal patterns of larval fish supply and settlement is a key step in understanding the connectivity of meta-populations (Sale et al., 2005). Because of the potentially dispersive nature of the pelagic larval phase of most reef fishes, tracking cohorts from hatching to settlement is extremely difficult (but see Jones et al., 1999). However, for many studies it is sufficient to sample larvae immediately before settlement. Many coral reef fish species use mangrove and seagrass beds as nursery habitats (Nagelkerken et al., 2001; Mumby et al., 2004) and larvae of these species must pass over the reef crest in order to arrive at their preferred settlement habitats. The ability to sample this new cohort of larval fishes provides opportunities for researchers to explore the intricacies of the transition from larva to juvenile (Searcy and Sponaugle, 2001). Quantifying the potential settlers also provides valuable information about the spatial and temporal supply of presettlement larvae (Victor, 1986). Therefore a number of larval sampling methods were developed, one of which is the use of crest nets (Dufour and Galzin, 1993).

Effect of towing speed on retention of zooplankton in bongo nets

Long-term time series of zooplankton data provide invaluable information about the fluctuations of species abundance and the stability of marine community structure. These data have demonstrated that environmental variability have a profound effect on zooplankton communities across the Atlantic basin (Beaugrand et al., 2002; Frank et al., 2005; Pershing et al., 2005). The value of these time series increases as they lengthen, but so does the likelihood of changes in sampling or processing methods. Sam-pling zooplankton with nylon nets is highly selective and biased because of mesh selectivity, net avoidance, and damage to fragile organisms. One sampling parameter that must be standardized and closely monitored is the speed of the net through the water column. Tow speed should be as fast as possible to minimize net avoid-ance by the organisms, but not so fast as to damage soft bodied zooplankters or extrude them through the mesh (Tranter et al., 1968; Anderson and Warren, 1991).

Safety net or debt net?: ties between marketing and credit in coastal Bangladesh

Three fishing communities in coastal Bangladesh namely: 1) Hindu community near Chittagong; 2) Muslim community in Rehania; and 3) Bhuddist community of Rakhaipara were studied, and each shared the same credit marketing system.

Safety Training and Oceanic Fishing

This paper reports on the cultural adaptation of Atlantic commercial fishermen to the danger of their occupation and efforts to ameliorate that danger through safety training programs. The research is directed towards measuring fishermen's patterns of subjective perceived danger and assessing the impact of safety training on these patterns of thinking. Safety training for commercial fishermen has unique problems owing to a culture that relies heavily on the trivialization or denial of the dangers associated with the work (Binkley, 1995; Poggie et al., 1995, 1996; Pollnac et al., 1995). Hence, understanding the efficacy of various approaches to safety training is important in promoting greater safety at sea, for this understanding will help create the most effective programs.

Trawling Operations and South African (Cape) Fur Seals, Arctocephalus pusillus pusillus

South African (Cape) fur seals, Arctocephalus pusillus pusillus, interact with the South African trawl fisheries-offshore demersal, inshore demersal, and midwater fisheries. These interactions take thef ollowing forms: Seals take or damage netted fish, on particular vessels they become caught in the propeller, seals drown in the nets, live seals come aboard and may be killed. Except in specific cases of seals damaging particular trawler propellers, interactions result in little cost to the offshore and midwater trawl fisheries. For the inshore fishery, seals damage fish in the net at an estimated cost in excess of R69, 728 (US$18,827) per year, but this is negligible (0.3%) in terms ofthe value of the fishery. Seal mortality is mainly caused by drowning in trawl nets and ranges from 2,524 to 3,636 seals of both sexes per year. Between 312 and 567 seals are deliberately killed annually, but this most likely takes place only when caught and they enter the area below deck, where they are difficult to remove, and pose a potential threat to crew safety. Overall, seal mortality during trawling operations is negligible (0.4-0.6%) in terms of the feeding population of seals in South Africa.

International legal instruments relevant to fisheries and fishing communities : a handbook. Theme V. Fishing vessels and safety at sea

This handbook provides detailed information for a wide range of legal instruments relevant to fisheries and fishworkers. It covers 114 legal instruments, categorized into the following seven themes: Theme I. Human Rights, Food Security, Women and Development. Theme II. Environment and Sustainable Development. Theme III. Oceans and Fisheries Management. Theme IV. Environmental Pollution Theme V. Fishing Vessels and Safety at Sea Theme VI. Labour Theme VII. Trade The handbook also includes the working of the instruments (decision-making bodies, monitoring and implementation agencies, periodicity of meetings, rules for participation in meetings of the decision-making bodies and implementation agencies for States and non-governmental organizations), regional instrument and agencies. Apart from being a ready reckoner to the instruments, it highlights the important sections of relevance to fisheries or small-scale fisheries and fishworkers. The companion CD-ROM provides the full texts of the instruments in a searchable database. The handbook will be useful for fishworker and non-governmental organizations, and also for researchers and others interested in fisheries issues.