Report of the Working Group on the Application of Genetics in Fisheries and Mariculture (WGAGFM) [24-27 March 2006 Newport, Ireland]

Contributors: Torild Johansen, Halvor Knutsen

The Working Group on the Application of Genetics in Fisheries and Mariculture (WGAGFM) met at the Marine Institute, Newport Ireland April 24–27, 2006. The meeting was well attended; with in total 18 representatives present from 10 countries (nine national delegates and nine experts appointed by the Chair). Five terms of reference were on the agenda for 2006. The first issue addressed was that of genetically based domestication in fish and shellfish by unintentional (natural) selection in the hatchery environment. To a large extent these genetic changes are related to the relaxation of selection pressures on traits important in the wild (e.g. reproduction, migration, predator avoidance). There is ample evidence for domestication in fish, with carp and salmon as the most prominent case studies. For shellfish evidence of domestication is also apparent, in particular in relation to selection of brood-stock. The group recommends recognising both intentional and unintentional domestication in aquaculture as powerful evolutionary forces to improve production in aquaculture, but also makes a cautionary note in association with release or escape of domesticated hatchery fish and their potential impact on wild populations. GSI (Genetic Stock Identification) now allows determination of the structuring of fish stocks into breeding populations and the estimation of proportions of contributing populations in mixed aggregations with high precision. To further exploit the immense potential of GSI in fisheries management it is necessary to improve the integration, accessibility and management of existing and future genetic information. Also, it is of paramount importance to preserve and catalogue irreplaceable archival biological material (e.g. historical scales and otoliths), which can be used “to go back in time” and serve as reference or baseline material to reveal genetic changes in populations. The group recommends the establishment of genetic “meta-databases” managed by organisations such as ICES responsible for coordinating and improving the biological data platform on which management of fisheries is based. The group discussed the subject of local adaptation in marine fish populations. Failing to recognize locally adapted populations in fisheries management and conservation biology will result in erroneous estimation of short term demographic processes as well as long term population dynamics and response to harvesting and global change. The group produced a very thorough review aimed at the non-specialist explaining what local adaptation is, how to detect local adaptation and in addition provided a number of case studies. The group recommends that current knowledge of genetic basis of adaptive heterogeneity should be incorporated into fisheries management and more research should be diverted towards demonstrating local adaptation in the wild, identifying the environmental drivers responsible for local adaptation and in turn elucidating the genetic basis of important adaptive traits. The TOR proposed in 2005 “Assess, through a case study of anadromous salmonids, the potential of genetic and spatial data analysis methods for resolving spatial boundaries of finfish and shellfish populations..” was postponed to 2007 since Professor Tom Cross who was to lead for this TOR was unable to attend the meeting. Finally, the WG assessed the genetic effects of the introgression of farmed Atlantic salmon on wild salmon populations, following a request from NASCO (North Atlantic Salmon Conservation Organisation). Recently there have been a number of important new studies, which have been adding information to our general good understanding of the effects of the interactions between farmed and wild salmon. Accordingly, the group summarized and discussed this new information, particularly its potential to improve management of wild fisheries. A number of the group members were involved in a very recent review of the impact of farm escapes (Ferguson et al., 2006) consequently (with the kind permission of the authors) some of this text was used to provide a part of the advice here.