Analysing the Potential for Genetic Change in Pike Populations Exploited by Recreational Fisheries

Goal To analyze the possibility for recreational fishing to induce genetic changes in exploited fish populations, and thereby to increase awareness of such potential among stakeholders and stimulate increased research effort and long-term monitoring of fish populations exploited by angling fisheries. As a result of selective (i.e. non-random) mortality, exploitation of wild living resources can directly or indirectly act as an (often overlooked) evolutionary force (Stokes et al. Fishing-induced selection has been identified as having the potential to alter the genetic architecture of fish populations, leading to changes in stock properties such as long-term yield and demographic traits such as size and age at maturation or growth rate Although much of the available evidence of a potential evolutionary effect is still inconclusive, it seems necessary to include its implications in sustainable fisheries management strategies (Law 2000; Heino & Godø 2002). This, inter alia, results from the precautionary approach to fisheries management and the internationally binding Convention on Biodiversity that demand that fishing effects should be reversible, and not irreversibly alter biodiversity of evolving natural resources, neither at the level of species nor communities. Until now, empirical and theoretical research on potential adaptive change induced by fishing has mostly focused on commercial exploitation in the marine environment or in Godø 2002 and references therein). In industrialized countries of the temperate regions, recreational fisheries (angling) systems constitute important socio-ecological systems that involve millions of people exploiting thousands of different freshwater fish stocks (Arlinghaus et al. 2002). As a result, substantial social and economic benefits are generated (Arlinghaus 2004a, 2004b). But the ecological and evolutionary impacts of angling fisheries are less well understood. Furthermore, the systems' behavior and management has not been studied thoroughly, and most research on recreational fisheries appears parochial, with a strong national orientation and relatively small frames of reference in terms of theory, concepts, models, and empirical bases (Aas 2002). As ecological processes and anthropogenic impacts of fisheries can only be understood at a more regional or local level, recreational fisheries systems provide an alternative to analyze fishing-induced genetic changes and natural resource-people interactions. As such, the development of predictable models in recreational fisheries 3 would increase our understanding of the interplay between social and ecological systems and expand the awareness of potential fishing-induced genetic change to the angling environment, particularly in freshwater ecosystems. Some features of angling practices such as the release of caught fish are unique in …