Published: 19/9/2014 | 2450 views
This is the proceedings of the an international symposium organised for stakeholders involved in the JICA-assisted projects in Cambodia, Lao PDR, Myanmar, Benin and Madagascar. The main objective of this symposium was to provide a venue for information sharing on extension of small-scale aquaculture, specifically targeted to those individuals and relevant organizations involved in various aquaculture development projects. The symposium also assessed the effectiveness of "farmer-to-farmer" extension approaches in the implementation of relevant aquaculture development projects in the region.
Published: 18/5/2007 | 3913 views
This paper provides guidelines for fish stock assessment and fishery management using the software tools and other outputs developed by the UK Department for International Development?s Fisheries Management Science Programme (FMSP) in the years 1992 to 2004. Part 1 describes some key elements of the precautionary approach to fisheries management. A stock assessment process is also outlined that can provide the information needed for such precautionary management. The management process summarized in Chapter 2 is based on recent FAO guidance, including the Code of Conduct for Responsible Fisheries. It emphasizes the need for setting goals and operational objectives; for defining these explicitly as reference points for a range of fishery indicators; for adopting decision control rules that include precautionary thresholds allowing for uncertainties and risk tolerances, and that drive fishery management using a set of measures that are pre-agreed with stakeholders. Chapter 2 also stresses the need to integrate use rights and co-management arrangements into the management framework, where appropriate, as key elements for success.
Chapter 3 presents the process of stock assessment, underlining the need for quantitative assessment of uncertainties and risks and the provision of advice based on the various goals of the fishery and considering both short- and long-term impacts of management strategies. Methods are given to estimate the current status of the fishery either as the stock size, the fishing mortality rate or other ecological or goal-based indicators. Methods are also described for estimating maximum sustainable yield (MSY) and other yield-based reference points, as well as some aimed at protecting the spawning capacity of the stock and avoiding recruitment overfishing. For sustainable exploitation, it is recommended that yield-based reference points are used as targets while spawning capacity reference points are used as limits and given the higher precedence. Precautionary thresholds should be set to prevent the limits being exceeded.
Chapter 4 provides information on the FMSP stock assessment tools and guidelines, including four FMSP software packages ? LFDA, CEDA, Yield and ParFish ? by which intermediate parameters, indicators and reference points may be estimated. The inputs and outputs and the relative advantages and potential uses of the tools are described. The four chapters in Part 2 further describe these four software tools, providing guidelines on their use and the fitting of models. Full technical details and tutorials are available in the software help files provided on the accompanying CD-ROM.
Part 3 then summarizes the guidelines produced by a number of other FMSP projects relating to stock assessment and management approaches that were introduced in Chapter 4. Chapter 10 uses simulation models to compare the performance of length based and age-based approaches for two tropical fish species. The analysis demonstrates the benefits of using age based approaches where possible, but it is noted that results may differ for other species and their particular life history strategies. Chapter 11 develops simple relationships for the estimation of potential yield and maximum sustainable fishing mortality based on the Beverton and Holt ?life-history invariants?. These relationships allow sustainable yields and fishing capacity to be estimated from sparse data, which may either be already available, or can be relatively easily obtained. Chapter 12 derives guidelines for the management of multispecies demersal bank and deep reef slope fisheries exploited principally with hooks and lines. Chapter 13 presents a Bayesian stock assessment applied to the Namibian orange roughy fishery. This case study illustrates the benefits and some of the difficulties found in applying the Bayesian approach and draws out some lessons learnt. Chapter 14 describes a number of empirical modelling approaches that can be used to support fisheries management, ranging in complexity from simple methods that only require historical catches through to complex multivariate models based on General Linear Modelling and Bayesian network approaches. These approaches may suit data poor circumstances, or when among fishery comparisons are possible, for example under adaptive approaches to (co-) management.
Throughout the framework, the use of adaptive learning and feedback approaches are promoted within the general principle of precaution. Complementary use of these approaches should enable uncertainties to be reduced and long-term benefits to be maximized with reduced risks to the resource base.
Hoggarth, D.D.; Abeyasekera, S.; Arthur, R.I.; Beddington, J.R.; Burn, R.W.; Halls, A.S.; Kirkwood, G.P.; McAllister, M.; Medley, P.; Mees, C.C.; Parkes, G.B.; Pilling, G.M.; Wakeford, R.C.; Welcomme, R.L. Stock assessment for fishery management ? A framework guide to the stock assessment tools of the Fisheries Management Science Programme (FMSP). FAO Fisheries Technical Paper. No. 487. Rome, FAO. 2006. 261p. Includes a CD-ROM.
Published: 31/5/2005 | 2905 views
The Trans-Himalayan region encompasses a number of countries situated in the midland and highland areas of the Himalayas, Karakoram, and in a broad sense also in Hindu Kush and Pamir. The mountains are characterized by a very low level of human development, with full exploitation or overexploitation of the natural resources. Fisheries play an important role in providing food and income to the mountain people. The Symposium on Cold Water Fishes of the Trans-Himalayan Region, held 10-13 July 2001 in Kathmandu, Nepal, was attended by 70 participants from 10 countries. In 32 presentations it reviewed information, experiences, ideas and findings related to fish and fisheries in the region, paying special attention to fish species distribution, fishing intensity, socio-economic conditions and livelihoods of fisher communities, as well as to the impact of environment degradation, conservation measures and aquaculture technologies for indigenous and exotic cold water fish. The Symposium highlighted the role that fisheries play in providing food and income to people within the Trans-Himalayas and Karakoram. Recognizing the need to increase the role of aquatic resources in poverty alleviation, the Symposium urged national governments to give greater attention to fisheries development in mountain areas. The Symposium put forward a number of priority issues, including collaborative action on a regional scale, which would probably be the most cost-effective way to address these common problems and to share experiences. The recommendations are expected to be addressed in follow-up activities under a Trans-Himalayan regional programme.