Stock structure, uncertainty, and holistic management of Pacific herring fisheries in the Strait of Georgia

Harvest control rules applied to aggregates of individual stocks or life history types can have pronounced small scale effects. Pacific Herring are currently managed as discrete stocks (5 major, 2 minor), and historical analyses of mark-recapture tagging data are consistent with this approach. Spati...

Full description

Bibliographic Details
Main Authors: Cleary, Jaclyn, Benson, Ashleen, Taylor, Nathan, Cox, Sean P
Format: Text
Language:English
Published: Western CEDAR 2017
Subjects:
Online Access:https://cedar.wwu.edu/ssec/2016ssec/species_food_webs/94
Description
Summary:Harvest control rules applied to aggregates of individual stocks or life history types can have pronounced small scale effects. Pacific Herring are currently managed as discrete stocks (5 major, 2 minor), and historical analyses of mark-recapture tagging data are consistent with this approach. Spatial distribution within discrete stocks may be both ecologically significant and important for local fishing opportunities. Neither the large inter-area nor the small intra-area scale spatial dynamics are explicitly considered in assessment and management processes. For example, within the Strait of Georgia, there has been a northward movement of spawning aggregations and an absence of spawning herring in previously occupied southern locations. Changes in herring spawning distribution have also been observed in the adjoining Puget Sound and elsewhere in British Columbia (BC). The reasons for such shifts are uncertain at this time. While the ecological processes driving herring spatial dynamics are uncertain, the cultural significance of herring is well documented. Given their importance for coastal First Nations (FN) communities, changes in spatial distribution that result in an absence of herring spawn in the waters neighboring FN communities limits access to food, social, and ceremonial harvest and cultural connection with this resource. In this talk, we will present our on-going research that evaluates: i) the management implications of spatial structure within, and connectivity among complex herring sub-populations or “stocklets”, and (ii) the potential influence of straying between major/ minor stock areas over time on our perception of herring stock status at both large and small scales.