The majority of monitored fish stocks globally is fully or over exploited, that is, at or below their maximum sustainable yield stock levels. Despite this resource situation international trade in fish products have been increasing for a long time. An export tax on fish and fish products, as an alternative...
This paper studies the potential for cooperation in shared fisheries when the countries in the coalition act in a Stackelberg fashion with respect to the remaining singletons. An increase in the cooperation level is a social welfare improvement, leading to an increase in both the steady-state fish stock and total...
The Lofoten fishery exploits the spawning migration of the Northeast- Arctic cod and is one of the fisheries in the world with the longest history. Since 1860, data on participation and catches in the Lofoten fishery are available. For about a hundred years, labor productivity in this fishery, measured as...
About 25% of the world's fisheries are depleted such that their current biomass is lower than the level that would maximize the sustained yield (MSY). Using methods not previously applied in the fisheries conservation context, we show in four disparate fisheries (including the long-lived and slow-growing orange roughy) that the...
Age and size at maturity are key life-history traits in a fish stock. At the individual level age and size at maturity affect fecundity, growth and survival. At the population level these factors interact to affect age and size distribution, the population dynamics and the productivity of the stock. A...
According to conventional economic wisdom the economically more efficient technology will always outcompete the less efficient. This hypothesis has usually been taken to hold for the exploitation of common pool renewable natural resources such as fish stocks. This paper claims that, while this is not necessarily false, it may be...
Efficient management of small-scale fisheries resources demands adequate human and financial resources. This mainly relates to research and enforcement activities. Despite the resource constraint, the state has assumed the role of managing the fisheries resources. The emerging global trend, however, recommends cost recovery systems for sustainable fisheries management to achieve...
There is growing recognition worldwide that the impacts of fishing on non-targeted components of marine ecosystems should be included in the assessment of fisheries sustainability. This leads to the inclusion of new constraints in evaluations of the long-term bio-economic performance of fisheries. In this paper, we analyze the implications of...
A model for studying how destructive fishing practices may affect commercial fish stocks through their effect on habitat is presented. It may be used both for renewable habitat-types, like eelgrass (Zostra marina) or sponges, and also practically non-renewable habitats like corals. The model demonstrates the trade-offs between using destructive and...
In many situation, fishing activity adversely impacts the state of the marine ecosystem, impacts which feed back to affect fish stocks. Some ecosystems appear to have multiple equilibria and exhibit hysteresis, whereby they can become stuck in low productivity states. We show how adding ecosystem dynamics to a classic fisheries...