Balanced harvesting, where species or individuals are exploited in accordance with their productivity, has been proposed as a way to minimize the effects of fishing on marine fish communities and ecosystems. This calls for a thorough examination of the consequences balanced harvesting has on fish community structure and yield. We use a size- and trait-based model that resolves individual intera...

Harvesting strategies in a fish stock dominated by low-frequency variability: The Norwegian spring-spawning herring (Clupea harengus). Marine Resource Economics 18: 263–274. Enberg, K. 2005. Benefits of threshold strategies coupled with age-selective harvesting in a highly variable fish stock: Norwegian spring-spawning herring (Clupea harengus) as an example. Marine Ecology Progress Series, in ...

Human harvesting of fish results in far greater mortality than natural causes, with enormous potential to affect the phenotypic traits of fish populations, even after exploitation stops. Central to understanding these effects is the untangling of the genetic versus environmental components of phenotypic response. Evolutionary consequences of harvesting must be incorporated into conservation and...

With increasing fishing pressures having brought several stocks to the brink of collapse, there is a need for developing efficient harvesting methods that account for factors beyond merely yield or profit. We consider the dynamics and management of a stage-structured fish stock. Our work is based on a consumer-resource model which De Roos et al. (in Theor. Popul. Biol. 73, 47-62, 2008) have der...

Today, fishing is the major source of mortality in many harvested fish stocks. The new high fishing mortality regime may induce evolutionary change in the harvested population, because the currently observed life-history patterns in fish stocks presumably reflect adaptation to past mortality regimes. Changes in these life-history patterns are likely to have an influence on, for example, the sus...

The paper is concerned with the optimal harvesting of a marine resource, described by an elliptic equation with Neumann boundary conditions and a nonlinear source term. Since the cost function has linear growth, an optimal solution is found within the class of measure-valued control strategies. The paper also provides results on the existence and uniqueness of strictly positive solutions to the...

We propose a dynamic model for studying the time evolution of fish stocks in an environment divided into two adjacent zones with different fishing policies. We analyze two particular harvesting methods: constant fishing effort and profit maximization. In this case, some agents engage in competition based on maximization of individual profit whereas others cooperate. The asymptotic behavior of t...

The objective of this study was to describe the different surgical approaches involved in harvesting and heterotopic autotransplantation of intact ovaries with microvascular anastomosis. Twenty-one synchronized Merino sheep underwent harvesting of their intact ovaries with vascular pedicles. Autotransplantation was performed with fresh (n = 6) and cryopreserved-thawed (C-T; n = 15) ovaries. The...

The efficacy of crude pineapple juice obtained from Ananus comosus in digesting fish for the harvesting of trematode metacercariae was investigated. No significant difference was found between the total number of metacercariae detected from fish (Cirrhina jullieni) digested by acid pepsin and those digested by freshly prepared pineapple juice that was kept for 15 days at a temperature of either...