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1. Fisheries CompetitionCommercial fisheries potentially cause or contribute to nutritional stress in the western stock of Steller sea lions by reducing either the abundance of prey at scales relevant to foraging sea lions or by disturbing prey patches so as to reduce their availability. In turn, nutritional stress is manifested in the population as increased mortality or lowered reproductive output. 2. Environmental ChangeEnvironmental conditions in areas inhabited by Steller sea lions may have changed since the 1970s in ways that reduced the availability of prey for Steller sea lions and precipitated nutritional stress. The changes may have either reduced the abundance of important prey items or altered their distributions. 3. PredationPredation of Steller sea lions by killer whales and sharks has increased as a function of a) their 4. Anthropogenic EffectsOne or more sources of anthropogenic activity, including incidental mortality (e.g. entanglement), direct mortality (e.g. shooting), commercial harvesting, subsistence harvesting, and harassment have contributed to the decline in the Steller sea lion population. Such effects would include both those over the past decades since the decline began and those which may be ongoing. 5. DiseaseThe Steller sea lion population is being reduced by diseases which may result in mortality or 6. ContaminantsContaminants from either local or distant sources have had detrimental physical impacts on Steller sea lions leading to increased mortality or reduced reproductive output. 7. SynergiesSeveral of the research projects, particularly those that have a modeling component, specifically address how fisheries and environmental effects could combine in an unpredictable manner to reduce prey availability, abundance or quality to sea lions. All possible combinations of effects were addressed in a single question 
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