Recent work on marine survival in Chinook and coho salmon and steelhead trout has shown a decline in marine survival in the Salish Sea that was not evident in other regions. For Chinook, the decline was not explained well by oceanographic patterns, and for coho, regional-scale patterns were suggested as important in understanding survival. Recent work on the development of indicators of Puget Sound steelhead survival has shown that predator abundance and patterns in hatchery releases, as well as oceanographic conditions are informative in predicting marine survival. While the three species of focus for the Salish Sea Marine Survival Project have different life-histories, and are therefore subjected to variable pressures at multiple scales, this current analysis aims to answer three questions: 1.) Are there similarities in survival trends among the three species? 2.) Do regional patterns in survival emerge when survival trends are evaluated concurrently across the three species? 3.) Does release strategy (yearling or subyearling) confer a survival advantage, and if so, is this consistent across all species? To evaluate survival time series, we used multivariate time series analysis with multiple groupings (species, spatial, and release strategy) to identify commonalities among species. Observed commonalities will aid in the development of indicators of marine survival for coho and Chinook by focusing efforts on appropriate spatial or temporal attributes. A hypothesis-driven approach similar to that employed for the development of indicators for steelhead survival will be used to relate coho and Chinook to environmental, biological, and anthropogenic factors influencing survival
