Indigenous Knowledge Systems Paired with Western Science Strengthen Ecosystem Approaches to the Management of Forage Fish

Ecosystem Approaches to Fisheries Management (EAFM) strive to manage stocks in ways that account for species interactions and changing environmental conditions. To date, management institutions have relied on Western science to support EAFM, dismissing the knowledges and practices of Indigenous Peoples who have long managed sustainable relationships between people and marine ecosystems. Indigenous Knowledge Systems (IKS) are ways of living in the world that intertwine governance, values, empirical observations, harvesting practices, and other elements that support the peoples who give rise to such knowledge. IKS and Western science overlap conceptually yet have complementary differences that, when paired together, can improve fisheries management. We developed a suite of semiquantitive indicators of the extent to which management advice documents (e.g., stock assessments and rebuilding plans) address key elements of EAFM and applied these indicators to a case study of 18 stocks of forage fish in Canada. Management advice matched the scale of demographic units for 44% of stocks; the remainder were managed as large units not defined by demographic criteria, potentially increasing the risk of local collapses. Temporal changes in size - and/or age-related traits were examined for 83% of stocks; however, objectives for rebuilding size and age structures, which affect per capita fecundity and transmission of learned behaviours, were specified only for Pacific herring in Haida Gwaii. Reference points that consider the ecosystem role of forage fish were applied to only three stocks (17%), of which only 2 had associated harvest control rules. Temporal variation in stock assessment parameters was accounted for in 61% of stocks and environmental variables were used to qualify management advice for half the stocks. Overall, indicator scores were highest for Pacific herring in Haida Gwaii, for which a rebuilding plan was co-produced by the Haida Nation and federal agencies. In this plan, Haida knowledge “contributed to the approach and analyses through understanding about spatial dynamics, informing historical baselines and reference points, documenting climate and predator changes, and knowledge about the effects of and interactions among fisheries.” Based on our results, we conclude with recommendations on how to strengthen EAFM advice that is inclusive of IKS.