Terms of Reference

Maritimes Region River Herring Framework and Case Study Application to the Tusket River Fishery

Regional Peer Review – Maritimes Region

February 9-11, 2016
Dartmouth, NS

Chairperson: Mark Showell

Context

Alewife (Alosa psuedoharengus) and blueback herring (Alosa aestevalis) are collectively known as river herring. These diadromous species return to the majority of river systems in Nova Scotia and Southwest New Brunswick and are fished together. The fishery is geographically widespread, with fishing practices and gear types that differ among rivers, and is managed through effort controls. The last river herring assessment in the Fisheries and Oceans Canada (DFO) Maritimes Region was for alewife in the Gaspereau River in 2007 (DFO 2007). There has not been a region-wide assessment since 2001 (DFO 2001). Towards the goal of developing an ongoing river herring assessment program in the region, science advice is being sought with respect to: 1) how best to monitor abundance of river herring stocks; 2) how best to evaluate the effects of their fisheries; and 3) how best to determine reference points that can be used to evaluate the status of the populations and their fisheries. The advice should take into consideration the highly variable characteristics of the watersheds, their fisheries and the potential for data collection. The river herring fishery in the Tusket River and estuary was selected as a case study to be assessed using the proposed framework based on input from DFO Resource Management and DFO Fishery Protection Program requirements. It is expected that this framework will identify data deficiencies, monitoring and research requirements, and will identify uncertainties in providing robust advice on regional river herring assessments.

Objectives

• Characterize the appropriate spatial scales for assessment and advice that takes into consideration population differentiation, variability among the various fisheries, as well as other factors that may affect abundance. Evaluate the potential to develop Index Rivers for regional assessment and advice.
• Evaluate the options for data collection and the associated assessment methods that are possible in different regions or rivers; specifically, as related to fishery-independent abundance metrics (total abundance estimates and/or relative indices, characterization of the fishery, and the development of reference points).
• Consider the effect of other human activities on rivers (e.g., dams) and how these would impact the above.
• Provide advice on how each run should be sampled in order to estimate abundance, quantify the commercial landings, and determine species composition, age and size distributions and other characteristics of the run
• Focus on sampling design within a year (i.e. sampling constant numbers (daily, weekly) vs. sampling proportional to abundance).
• Focus on sampling frequency among years (e.g. every year, every other year and so on) required in order to detect trends in these characteristics or to appropriately evaluate status
• Evaluate the data collection and assessment methods as applied to the alewife and blueback herring populations in the Tusket River and the resulting determination of their status.
• Provide research recommendations to address uncertainties and gaps in the assessment framework.

 Expected Publications

• Proceedings
• Research Document(s)

Participation

• DFO Science
• DFO Fisheries & Aquaculture Management
• DFO Fisheries Protection Program
• Aboriginal communities/organizations
• Provincial (NS, NB) governments
• Fishing Industry
• Academics
• Environmental Non-Government Organizations

References

DFO. 2001. Gaspereau Maritime Provinces Overview. DFO Science Stock Status Report D3-17 (2001).

DFO. 2007. Assessment of Gaspereau River Alewife. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2007/030.