Hybridization of farmed escaped and wild Atlantic salmon: so what? An empirical and model based exploration of the consequences for wild populations throughout the North Atlantic

PARR-2016-NL-11

Description

The farming of Atlantic salmon now exceeds 2 million tonnes worldwide, exceeding the natural production of wild populations. Interbreeding between wild and escaped farmed salmon has been reported both in Europe and North America and can alter wild population characteristics, eroding local adaptation and causing wild population declines. However, the extent and magnitude of these genetic impacts are difficult to predict. The resiliency of wild populations, the recovery time following hybridization, and the efficacy of possible mitigation strategies remain unclear.

The overall goal of this international collaborative research project is to provide the basis for robust scientific advice regarding the genetic impacts of escaped farmed Atlantic salmon on wild populations both locally (i.e., Newfoundland) and across the North Atlantic. As well, potential successes of various mitigation strategies will be explored by using data collected in parallel research projects from across the North Atlantic. This work will directly complement existing studies and will

1. quantify the magnitude of hybridization among wild and escaped farmed salmon and explore growth, survival and biological differences among wild and hybrid individuals, and
2. develop an international collaborative project, under the Canada/US/EU Galway Declaration, focused on evaluating different models used throughout the North Atlantic.

Identifying risks and potential mitigation strategies associated with Atlantic salmon aquaculture escapees is necessary for the successful conservation of wild salmon populations, the stability of recreational and Aboriginal fisheries, and continued growth of a sustainable aquaculture industry. Through an examination of the presence of interbreeding and introgression, this work will help identify strategies for maintaining the rapid growth of the aquaculture industry without altering population structure or local adaptation of wild salmon populations. By doing so, this work will directly assist DFO in meeting Canada's commitment to sustainable development in aquaculture.

Findings

N/A

Publications

N/A

Program Name

Program for Aquaculture Regulatory Research (PARR)

Year(s)

2016 to 2019

Ecoregion(s)

Atlantic: Newfoundland, Labrador Shelves

Principal Investigator

Ian Bradbury
Research Scientist, Northwest Atlantic Fisheries Centre
Email: Ian.Bradbury@dfo-mpo.gc.ca