Fisheries Society of the British Isles
International Symposium Exeter 23-27 July 2007

Symposium Outline

Non-native fishes: integrated biology of establishment success and dispersal

Translocations and introductions of fish species into areas outside their native range have a long history, with deliberate introductions for sport and food production intensifying during the last 100 to 150 years. The impacts of non-native fish introductions range from negligible to devastating, with the extinction of native species such as cichlids in Lake Victoria following the introduction of Nile perch. Only a small proportion of introduced species succeed in establishing a self-sustaining population, and consequently the probability of establishment is one of the central themes addressed in risk assessments of non-native species. Establishment in a novel environment is influenced by many interacting processes, including tolerance of environmental conditions (e.g. temperature, oxygen, salinity), human alteration of the environment, and species-specific adaptability (behavioural, physiological, reproductive, dietary, growth). Acclimatisation processes may be rapid or gradual, and establishment may be permanent or temporary, depending upon the genetic make-up of the founding populations - influenced by the frequency and size of introductions, and possibly facilitated by the presence of other non-native organisms, including parasites and pathogens, as well as by changes in environmental conditions (e.g. climate change, river regulation). Once established, the rates and routes for subsequent dispersal of introduced species are of particular interest for limiting or mitigating impacts. Knowledge of a species' dispersal patterns in its native range is not necessarily relevant to its introduced range. Therefore, research has been needed on the physiological and behavioural processes associated with dispersal in novel environments, especially integrated field (e.g. tracking) and laboratory studies of physiological tolerances and behaviour.

The Symposium will focus on the factors involved in the establishment success of non-native species and their subsequent dispersal, with emphasis on research that addresses these interactions through integrated studies of the development, life-history tactics, genetics, behaviour, biochemistry, ecological interactions and parasitology of non-native marine and freshwater fishes in novel environments.

In association with:   Environment Agency The Marine Biological Association CEFAS