Optimal management of conflicting species: Grey seal (Halichoerus grypus) and Atlantic salmon (Salmo salar) in the Baltic Sea

The objective of this thesis is to examine the economic effects in the conflict between grey seal population and the salmon fishery in the Baltic Sea. We will formulate a bioeconomic model which provides new insights on the optimal management of Atlantic salmon with respect to the effects brought about by the grey seal population. As the catch losses caused by seals have an effect on salmon fishery in Baltic, we will study how seal population affects the present value of the salmon fishery. The study considers the Finnish coastal trap net fishery. The bioeconomic model considers a scenario of sole salmon fishery and a scenario of salmon fishery affected by the grey seal population. On the basis of these scenarios, a seal compensation scheme is introduced. We can observe a significant economic seal-induced effect on the salmon fishery. The results suggest that the present seal compensation scheme emploid by the Finnish government is suboptimal. This thesis is part of the TARMO –project, in which the conflict between grey seal population and salmon fishery is studied using the methods of environmental economics.

Pulse vs. Optimal Stationary Fishing: The Northern Stock of Hake

Pulse fishing may be a global optimal strategy in multicohort fisheries. In this article we compare the pulse fishing solutions obtained by using global numerical methods with the analytical stationary optimal solution. This allows us to quantify the potential benefits associated with the use of periodic fishing in the Northern Stock of hake. Results show that: first, management plans based exclusively on traditional reference targets as Fmsy may drive fishery economic results far from the optimal; second, global optimal solutions would imply, in a cyclical manner, the closure of the fishery for some periods and third, second best stationary policies with stable employment only reduce optimal present value of discounted profit in a 2%.

Proposal for improving fishing opportunities off Pt. Loma by construction of an artificial reef

(Document pdf contains 42 pages)

Food habits of California Sea Lions (Zalophus californianus) and their impact on Salmonid Fisheries in Monterey Bay, California

In the ocean commercial troll and recreational salmon fishery in Monterey Bay California, California sea lions (Zalophus califomianus) will swim near or follow fishing boats and will depredate fish once hooked. The objectives of the study were to determine the percentage of salmon taken by pinnipeds in commercial and recreational fisheries, identify relative importance of prey items seasonally consumed by sea lions, and determine the proportion of salmonids in the sea lion diet on a seasonal basis. From April 1997 through September 1998, 1041 hours of onboard and dockside surveys of the commercial and recreational salmon fisheries were conducted at the three ports in Monterey Bay, California. Sea lions depreadated 7.9 % of the fish hooked in the commercial fishery in 1997 and 28.6 % in 1998,8.4 % (1997) and 18.3 % (1998) of the CPFV fishery, and 15.6 % (1997) and 17.5 % (1998) of the private skiff fishery. Increased depredation rates in both the commercial and recreational salmon fisheries in 1998 were most likely the result of the large EI Nino Southern Oscillation event that occurred in 1997-1998 during which a greater number of sea lions were present in central California. Prey hardparts identified in sea lion fecal samples collected in Monterey Bay indicated that schooling fishes were the predominant prey fish species, such as market squid (Loligo opalescens), Pacific sardine (Sardinops caeruleus), northern anchovy (Engraulis mordax), and rockfish (Sebastes sp.). Sea lions consumed similar prey species in the summer and fall 1997, winter 1997-98, and spring 1998 (PSI> 70.0) with market squid and northern anchovy being the dominant prey species. However, prey composition changed significantly during the summer 1998 and fall 1998 (PSI < 46.0) because of the increased importance of sardine and rockfish in the diet and the decreased importance of market squid. This report does not intend to imply that salmonids are not a prey species for pinnipeds in the Monterey Bay region, but highlights the difficulties encountered in establishing the role of salmonids in the pinniped diet when analyzing fecal samples. (PDF contains 38 pages).

ICSF guide book: understanding the Work in Fishing Convention, 2007

This guidebook attempts to provide a quick overview of the Work in Fishing Convention, 2007, which was adopted in Geneva, Switzerland, in June 2007 at the 96th International Labour Conference (ILC) of the International Labour Organization (ILO). It does not purport to provide interpretation of any provisions of the Convention and should not in any way be treated as a substitute for the actual provisions it contains. This guidebook is intended mainly to help those unfamiliar with the Convention and the working of the ILO and the ILC, gain some understanding of the relevant issues. In particular, it is hoped that the guidebook will aid fish workers and their organizations understand the possible benefits and implications of the Convention for artisanal and small-scale fisheries in developing countries.

Selectivity, pulse fishing and endogenous lifespan in Beverton-Holt models

Optimal management in a multi-cohort Beverton-Holt model with any number of age classes and imperfect selectivity is equivalent to finding the optimal fish lifespan by chosen fallow cycles. Optimal policy differs in two main ways from the optimal lifespan rule with perfect selectivity. First, weight gain is valued in terms of the whole population structure. Second, the cost of waiting is the interest rate adjusted for the increase in the pulse length. This point is especially relevant for assessing the role of selectivity. Imperfect selectivity reduces the optimal lifespan and the optimal pulse length. We illustrate our theoretical findings with a numerical example. Results obtained using global numerical methods select the optimal pulse length predicted by the optimal lifespan rule.

Fishing effort validation and substitution possibilities among components: the case study of the VIII division European anchovy fishery

Command and control regulation programs, particularly input constraints, typically fail to achieve stated objectives, because fishermen may substitute unregulated for regulated inputs. It is, thus, essential to have an understanding of the internal structure of production technology. A primal formulation is used to estimate a translog production function at the vessels level that includes fishing effort and fisherman’s skill. The flexibility of the selected functional permits the analysis of the substitution possibilities among inputs by estimating the elasticity of substitution with no prior constraints. Particular attention is paid to the empirical validation of fishing effort as an aggregate input, which implies either, the acceptation of the joint hypothesis that inputs making up effort are weakly separable from the inputs out of the subgroup or considering that effort is an intermediate input produced by a non-separable two stage technology. Cross sectional data from the Spanish purse seine fleet operating in the VIII Division European anchovy fishery provide evidence of limited input substitution possibilities among the inputs making up the empirically validated fishing effort translog micro-production function.

Forecasting Climate Impacts on Future Production of Commercially Exploited Fish and Shellfish

Foreword [pdf, < 0.1 MB] Acknowledgements PHASE 1 [pdf, 0.2 MB] Summary of the PICES/NPRB Workshop on Forecasting Climate Impacts on Future Production of Commercially Exploited Fish and Shellfish (July 19–20, 2007, Seattle, U.S.A.) Background Links to Other Programs Workshop Format Session I. Status of climate change scenarios in the PICES region Session II. What are the expected impacts of climate change on regional oceanography and what are some scenarios for these drivers for the next 10 years? Session III. Recruitment forecasting Session IV. What models are out there? How is climate linked to the model? Session V. Assumptions regarding future fishing scenarios and enhancement activities Session VI Where do we go from here? References Appendix 1.1 List of Participants PHASE 2 [pdf, 0.7 MB] Summary of the PICES/NPRB Workshop on Forecasting Climate Impacts on Future Production of Commercially Exploited Fish and Shellfish (October 30, 2007, Victoria, Canada) Background Workshop Agenda Forecast Feasibility Format of Information Modeling Approaches Coupled bio-physical models Stock assessment projection models Comparative approaches Similarities in Data Requests Opportunities for Coordination with Other PICES Groups and International Efforts BACKGROUND REPORTS PREPARED FOR THE PHASE 2 WORKSHOP Northern California Current (U.S.) groundfish production by Melissa Haltuch Changes in sablefish (Anoplopoma fimbria) recruitment in relation to oceanographic conditions by Michael J. Schirripa Northern California Current (British Columbia) Pacific cod (Gadus macrocephalus) production by Caihong Fu and Richard Beamish Northern California Current (British Columbia) sablefish (Anoplopoma fimbria) production by Richard Beamish Northern California Current (British Columbia) pink (Oncorhynchus gorbuscha) and chum (O. keta) salmon production by Richard Beamish Northern California Current (British Columbia) ocean shrimp (Pandalus jordani) production by Caihong Fu Alaska salmon production by Anne Hollowed U.S. walleye pollock (Theragra chalcogramma) production in the eastern Bering Sea and Gulf of Alaska by Kevin Bailey and Anne Hollowed U.S. groundfish production in the eastern Bering Sea by Tom Wilderbuer U.S. crab production in the eastern Bering Sea by Gordon H. Kruse Forecasting Japanese commercially exploited species by Shin-ichi Ito, Kazuaki Tadokoro and Yasuhiro Yamanka Russian fish production in the Japan/East Sea by Yury Zuenko, Vladimir Nuzhdin and Natalia Dolganova Chum salmon (Oncorhynchus keta) production in Korea by Sukyung Kang, Suam Kim and Hyunju Seo Jack mackerel (Trachurus japonicus) production in Korea by Jae Bong Lee and Chang-Ik Zhang Chub mackerel (Scomber japonicus) production in Korea by Jae Bong Lee, Sukyung Kang, Suam Kim, Chang-Ik Zhang and Jin Yeong Kim References Appendix 2.1 List of Participants PHASE 3 [pdf, < 0.1 MB] Summary of the PICES Workshop on Linking Global Climate Model Output to (a) Trends in Commercial Species Productivity and (b) Changes in Broader Biological Communities in the World’s Oceans (May 18, 2008, Gijón, Spain) Appendix 3.1 List of Participants Appendix 3.2 Workshop Agenda (Document contains 101 pages)

Fishing capacity management

Excess fishing capacity has been identified as one of the most pernicious problems affecting long-term sustainability and biodiversity of fishery resources and economic viability of fishing operations. Significant economic gains could be achieved by eliminating excess capacity, in addition to attaining objectives of resource sustainability. In this paper, approaches to fishing capacity management are reviewed in the context of Indian fisheries. A rights based regulated access system under a co-management regime based on a strong inclusive cooperative movement of stakeholders with built-in transferable quota system and buy-back or rotational right of entry schemes seems to hold potential for capacity management in the shelf fisheries of Indian states, which need to be implemented in collaboration with the Union Government and the neighboring states with confluent ecosystems and shared fishing grounds. A key advantage of the use of rights based approaches for managing fishing capacity is that they provide a mechanism through which stakeholders can more easily and actively participate in the management process.

The India MPA Workshop Proceedings. Social Dimensions of Marine Protected Areas Implementation in India: do Fishing Communities Benefit? 21-22 January 2009, IMAGE Auditorium, Chennai, India

In the current context of natural resource management, marine protected areas (MPAs) are being widely propagated as an important tool for the conservation of marine and fisheries resources. The International Collective in Support of Fishworkers (ICSF) recently undertook a series of studies on MPAs in India to highlight the various legal, institutional, policy and livelihoods issues that confront fishing and coastal communities. In order to discuss the findings of these case studies and to suggest proposals for livelihood-sensitive conservation and management of coastal and fisheries resources through participatory processes, ICSF organized a two-day workshop on ‘Social Dimensions of Marine Protected Area Implementation in India: Do Fishing Communities Benefit?’ at Chennai on 21-22 January 2009. This publication—the India MPA Workshop Proceedings—contains the prospectus of the workshop, a report of the proceedings and the consensus statement that was reached by organizations and individuals who particapated in the workshop. This publication will be useful for fishworkers, non-governmental organizations, policymakers, trade unions, researchers and others interested in natural resource management and coastal and fishing communities.

Fishing community issues in the Sundarban Tiger Reserve: a case study

The study focuses on fishing community issues in the Sundarban Tiger Reserve (STR). It provides an overview of the legal framework, and design and implementation of fishing regulations, and documents and analyzes the experiences of local fishing communities. It explores ways in which livelihood concerns can be appropriately balanced with conservation. The report builds upon a study titled ‘Traditional Fishers in the Sundarban Tiger Reserve’ (DISHA 2008) and draws upon secondary review of literature and field visits conducted in September 2008. The report is structured in six parts. The first part provides the legal background and the second sketches the status of fisheries and fishing communities. The third part focuses on livelihood issues within the STR, and community concerns regarding implementation of tiger protection measures. Part four explores the initiatives undertaken in the domain of alternative livelihoods. Part five offers a conclusion. The final sixth part, recognizing the initiatives that have been taken to address alternative livelihood options, lists the study's recommendations. (PDF contains 32 pages)