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Steller Sea Lion Research Themes and Sub-themes

  1. Life History - Investigations of the life history of Steller sea lions, including all aspects of ontogeny (e.g., weaning process, molt, growth) and reproduction. Studies of behavior are included as a sub-theme since the age and sex of the studied individuals are central to their behavior.

  2. Foraging - Studies of the foraging ecology of Steller sea lion juveniles and adults. This includes all aspects of foraging, including what is eaten (food habits and diet), the costs incurred in locating and obtaining prey (bioenergetics), and differences in habitat use by juveniles and adults (habitat use).

  3. Vital Rates - All studies related to population assessment (both counting of animals and assessment of their condition), reproductive rates, and survival/mortality rates (e.g. branding studies). Modeling studies, such as the creation of a new life table, would also fall under this theme. Many of these studies supply baseline information necessary to address all of the hypotheses/questions.

  4. Fish Assessment and Fisheries - Prey or fish surveys, along with any studies of the impacts of fisheries on either large scales (ecosystem-wide) or small spatial/temporal scales.

  5. Ecosystems - Any study dealing with bottom-up processes in the ocean and how changes in them might affect the prey field for Steller sea lions. There are two sub-themes: large scale (ecosystem-wide) studies or those addressing ecosystem processes at small spatial/temporal scales.

  6. Other Anthropogenic Effects - Any studies of the effects or quantification of subsistence hunting, intentional shooting, incidental take, or the residual effect of harvests and bounties on the Steller sea lion population. This theme, along with the following three, directly corresponds with one of factors causing or contributing to the decline.

  7. Predation - Killer whale and shark predation are sub-themes under this general research theme. These would include all studies whose primary focus is addressing questions. 

  8. Disease - Studies of sea lion diseases (including parasites) are included in one of two sub-themes, which evaluate the impacts of disease on:  1) individual sea lion health, and 2) the population of sea lions as a whole (population-level assessment).

  9. Contaminants - Similar to sea lion disease studies, contaminant studies were also placed into one of two sub-themes depending on the scale at which contaminant effects were analyzed: 1) assessment of the effects of contaminants on the health of individuals (individual health assessment), and 2) assessment of the effects of contaminants on sea lion habitats (environmental-level effects), and how this could reduce sea lion survival or births.

  10. Management - Projects under this theme involve funding for meetings to implement regulations (e.g., NPFMC), for independent reviews of actions, and for analysis of economic impacts of actions. Reviews address the scientific and legal information available and required to answer some or all of the questions posed, while other projects inform decisions made by managers.

  11. Communications - Communication of ideas and information both among researchers (coordination) and between researchers and the interested public (outreach) are the principal goals of projects under this theme. Forms of communication considered include symposia, publishing of scientific literature, and web-based content.