Terms of Reference

Evaluation and update of biologically-based targets for enhanced contributions to Chinook populations

Regional Peer Review Process – Pacific Region

August 31 – September 1, 2017
Nanaimo, British Columbia

Chairperson: Lesley MacDougall

Context

DFO’s Salmonid Enhancement Program (SEP) has guidelines for hatchery program management that  have been in place for many years in the Pacific Region, and have been used as part of an integrated enhancement planning process to address multiple biological and socioeconomic objectives.  Whereas over-arching SEP objectives are commonly framed in broad socioeconomic terms; management of risk to natural populations requires a detailed assessment of the nature, degree and duration of enhancement on a species, population and site-specific basis.

Key advancements have been made since the implementation of the existing enhancement guidelines, including the development  of Canada’s Policy for Conservation of Wild Pacific Salmon (the Wild Salmon Policy or WSP), the development of SEP’s Biological Risk Management Framework (SEP RMF), and collection of new scientific information on the level and nature of direct gene flow and genetic interactions (i.e. based on competition for resources or altered harvest regimes) between hatchery and wild fish. Additionally, the US hatchery reform process (HSRG) highlighted the distinction between ‘integrated’ and ‘segregated’ hatchery programs and the need to develop benchmarks consistent with the specific biological objectives set for hatchery programs.  The HSRG process also led to the development of the Proportion Natural Influence (PNI) metric as an indicator of the genetic influence of enhancement on a natural population. Chinook Salmon enhancement guideline updates that can be applied at the population level are required to ensure that: (a) guidelines can be developed to manage risk to fitness of natural populations resulting from the genetic influences of co-existing hatchery-origin salmon, (b) hatchery Chinook Salmon programs are planned and managed in a manner to better acknowledge and quantify biological risk while achieving the socio-economic benefits of enhanced fish, and (c) the biological risks of hatchery enhancement can be more transparently evaluated against the intended socioeconomic benefits.

DFO’s Salmonid Enhancement Program requested DFO Science provide advice on genetically based targets for enhanced contributions to Chinook Salmon populations. This advice will reflect new Canadian policy, new genetic information, assessment tools, and measurement metrics for the genetic effects of hatchery rearing and enhancement on wild fish. The advice will be used to support management of the genetic risks associated with the current types of enhancement programs in the context of Canadian policy, fisheries, and hatchery management, as well as provide a framework to better quantify the potential genetic risks of enhancement to wild populations and allow for explicit decision making regarding trade-offs between risk and socioeconomic benefit.

Objectives

The following working paper will be reviewed and provide the basis for discussion and advice on the specific objectives outlined below. 

Withler, R., Bradford, M., Willis D., and Holt, C. 2017. Genetically Based Targets for Enhanced Contributions to Canadian Pacific Chinook Salmon Populations. CSAP Working Paper 2013SEP02.

1. Review the current scientific understanding of observed and potential genetic risks to wild populations associated with hatchery propagation.
2. Describe categories of biological status for enhanced Chinook Salmon populations measured in terms of proportion of wild fish as defined in the Canadian WSP. Describe how to assess hatchery influence on Chinook Salmon populations, using the Proportion Natural Influence (PNI) metric, including its rationale and its applicability to the Canadian context.
3. Provide advice on quantitative benchmarks for the PNI and/or other appropriate metrics for the biological categories of status, and management measures to achieve those benchmarks.
4. Summarize the information and analyses needed to implement the PNI-based genetic risk management guidelines.
5. Summarize advice and guidance for development of new enhancement guidelines.

Expected Publications

• Proceedings
• Science Advisory Report
• Research Document

Expected Participation

• Fisheries and Oceans Canada (DFO) (Science, Fisheries Management, and Salmonid Enhancement Program)