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Climate-driven changes in ocean temperatures, currents, or plankton dynamics may disrupt pelagic forage fish recruitment. Being responsive to such impacts enables fisheries management to ensure continued sustainable harvest of forage species. We conducted a management strategy evaluation to assess the robustness of current and alternative Pacific sardine harvest control rules under a variety of recruitment scenarios representing potential projections of future climate conditions in the California Current. The current environmentally informed control rule modifies the harvest rate for the northern sardine subpopulation based on average sea surface temperatures measured during California Cooperative Oceanic Fisheries Investigations field cruises. This rule prioritizes catch at intermediate biomass levels but may increase variability in catch and closure frequency compared to alternative control rules, especially if recruitment is unrelated to ocean temperatures. Fishing at maximum sustainable yield and using dynamically estimated reference points reduced the frequency of biomass falling below 150 000 mt by up to 17%, while using survey index-based biomass estimates resulted in a 14% higher risk of delayed fishery closure during stock declines than when using assessment-based estimates. [ABSTRACT FROM AUTHOR]

Quantitative models for marine ecosystem-based management are often constrained by availability of observations. Uncertainty about the underlying system structure can affect model estimates and conclusions about the consequences of management actions. Qualitative models can augment model development for decision-making and may provide an alternative to quantitative assessments. We apply qualitative loop analysis to assess the sensitivity of management outcomes to structural uncertainty within the Georges Bank social-ecological system. Loop analysis uses defined positive or negative relationships between system components to provide inference about cascading effects of pressures on components of management interest. We compare the sensitivity of outcomes from two management strategies in four model structures of the Georges Bank system that investigate trophic and socioeconomic model uncertainty. We summarize system responses to perturbation and compare these responses with a set of management objectives. Models with complex socioeconomic structure estimated positive outcomes more often but with less reliability than simpler models. Our analyses demonstrated trade-offs among habitat objectives for two management strategies, as well as uncertainty about the reliability of outcomes, contingent on model structure. Les modeles quantitatifs pour la gestion ecosystemique en milieu marin sont souvent limites par les observations disponibles. L'incertitude concernant la structure sous-jacente au systeme peut avoir une incidence sur les estimations des modeles et les conclusions concernant les consequences de mesures de gestion donnees. Des modeles qualitatifs peuvent etre utiles au developpement de modeles pour la prise de decisions et peuvent constituer une solution de rechange aux evaluations quantitatives. Nous utilisons l'analyse en boucle qualitative pour evaluer la sensibilite des resultats de gestion a l'incertitude structurelle au sein du systeme socioecologique du banc de Georges. L'analyse en boucle fait appel a des relations positives ou negatives definies entre differents elements du systeme pour produire des inferences sur les effets en cascade de pressions sur des elements d'interet pour la gestion. Nous avons compare la sensibilite des resultats pour deux strategies de gestion dans quatre structures de modele du systeme du banc de Georges qui examinent l'incertitude de modeles trophiques et socioeconomiques. Nous resumons les reactions du systeme a la perturbation et comparons ces reactions a un ensemble d'objectifs de gestion. Les estimations de modeles caracterises par une structure socioeconomique complexe produisent des resultats positifs plus souvent mais de maniere moins fiable que les modeles plus simples. Nos analyses font ressortir des compromis entre differents objectifs lies aux habitats pour deux strategies de gestion, ainsi que l'incertitude associee a la fiabilite des resultats, selon la structure du modele. [Traduit par la Redaction], Introduction Marine ecosystem-based management requires a broad perspective to make informed decisions related to multiple social, economic, and environmental objectives (Mangel et al. 1996; Endter-Wada et al. 1998; Leslie and [...]

Despite years of effort from behavioral ecologists, animal behavior has not been fully integrated into the field of conservation biology. We propose a novel framework to join these fields through the use of demographic models. We present three strategies for incorporating behavior in demographic models, outline the costs of each strategy through decision analysis, and build on previous work in behavioral ecology and demography. We then provide practical recommendations for applying this framework to management programs. First, relevant behavioral mechanisms should be included in demographic models used for conservation decision making. Second, rapid behavioral assessment is a useful tool to approximate demographic parameters through regression of demographic phenomena on observations of related behaviors. Behaviorally estimated parameters may be included in population viability analysis for use in management. Finally, behavioral indices can be used as indicators of population trends. Rapid behavioral assessment holds promise as a cost-effective tool, but also represents a cost to model accuracy. We provide a framework for implementing rapid behavioral assessment through case studies of reproductive, foraging, and antipredator behaviors. We use a decision-theoretic approach to provide quantitative rules for identifying when metrics of animal behavior may be more meaningful than traditional population assessment. [ABSTRACT FROM AUTHOR]