Attending to spatial social–ecological sensitivities to improve trade‐off analysis in natural resource management

Abstract

Balancing trade‐offs amongst social–ecological objectives is a central aim of natural resource management. However, objectives and resources often have spatial dimensions, which are usually ignored in trade‐off analyses. We examine how simultaneously integrating social–ecological benefits and their spatial complexities can improve trade‐off analysis. We use Pacific herring (Clupea pallasii, Clupeidae)—an ecologically important forage fish with social, cultural and economic value to communities and commercial fisheries—as a case study. By combining spatial management strategy evaluation with social benefits analysis, we illustrate when policies aimed at aggregate stocks versus spatially segregated substocks of fish fail to balance trade‐offs amongst social–ecological objectives. Spatial measures (e.g. area‐based closures) may achieve some objectives but produce alternative trade‐offs that are sensitive to assumptions about fish population dynamics and social complexities. Our analyses identify policies that are inefficient (e.g. yielding economic costs without producing social or ecological gains), highlight management strategies that generate trade‐offs and indicate when costs are distributed unequally for different user groups. We also point to strategies with outcomes that are robust to spatial uncertainties and reveal research priorities by identifying which performance metrics exhibit sensitivity to spatial ecological assumptions. Collectively, our analyses demonstrate how incorporating social objectives and spatial dynamics into management strategy evaluation can reveal trade‐offs and the implications of management decisions.

Spatial variation in exploited metapopulations obscures risk of collapse

“…These outcomes highlight that ignoring space can exclude critical social, ecological, and economic responses central to the triple bottom line of natural resource management (Elkington , Okamoto et al. ).…”

“…), opportunities to integrate knowledge and objectives into management strategies (and their evaluation) at smaller spatial scales are well placed in managing these fisheries and may be critical to their perpetuity (Okamoto et al. , Salomon et al. ).…”

“…Mobile commercial fishing fleets harvest adult herring, largely for their roe, in the days prior to spawning. In contrast, Indigenous fishers are constrained to a local area and largely harvest eggs after spawning events (though some adults as well) as an important food, trade, and cultural resource (Lepofsky and Caldwell 2013, McKechnie et al 2014, Department of Fisheries and Oceans 2015, von der Porten et al 2016, Okamoto et al 2020. These activities create trade-offs among commercial roe fisheries that remove spawning adults, which truncates adult age structure and reduces abundance, vs. those that remove only eggs from shorelines (Shelton et al 2014).…”

“…These spatial scale dependencies affect which fishing communities or species bear the brunt of management risks and who reaps the benefits from the portfolio payoff of regional metapopulation stability. These outcomes highlight that ignoring space can exclude critical social, ecological, and economic responses central to the triple bottom line of natural resource management (Elkington 1994, Okamoto et al 2020. Pacific herring fisheries on Canada's west coast provide an empirical case where the scale of regional stock assessments masked episodic local overexploitation and subpopulation collapses.…”

“…, Okamoto et al. ). These activities create trade‐offs among commercial roe fisheries that remove spawning adults, which truncates adult age structure and reduces abundance, vs. those that remove only eggs from shorelines (Shelton et al.…”