1. NATURES (Project 199105500) Natural Rearing Enhancement System Resource Enhancement and Utilization Technologies Division Northwest Fisheries Science Center National Marine Fisheries Service 2725 Montlake Boulevard E. Seattle, Washington

2. Goals Increase postrelease survival Minimize morphological and behavioral divergence from wild fish

3. Summary of Major Results Achieved Seminatural raceway habitat –Induced wild-like behavior and coloration –Increased instream survival Predator avoidance conditioning –Increased instream survival –Increased predator recognition Ecological interactions –Improved competitive ability –Reduced behavioral divergence Feeds –Improved foraging skills 12 published papers

4. Objectives 1. Evaluate the independent and interactive effect of NATURES seminatural raceway habitat variables on chinook salmon smolt-to- adult survival. 2. Evaluate the effect of NATURES predator avoidance conditioning on chinook salmon smolt-to-adult survival. 3. Quantify the effects of hatchery steelhead reared in NATURES and conventional environments on the growth, survival, condition, and emigration of naturally-reared steelhead and chinook salmon. 4. Determine the effects of NATURES rearing on the behavioral development of juvenile steelhead and the effects of competition with naturally-reared salmonids. Address RPA 170-173, and 184

5. Carson NFH Experiments (Obj. 1 & 2) Seminatural Raceway Habitat Predator Avoidance Conditioning

6. Experiment evaluating the independent and interactive effects of NATURES Seminatural Raceway Habitat StructureNo structure No substrate CoverNo cover No structure Cover Structure Substrate No coverCover Eight rearing treatments Substrate No structure No substrate Structure Substrate No cover No structure No substrate Cover Structure Substrate No coverCoverNo coverCover Full factorial experimental design T1T2T3T4T5T6T7T8

7. Seminatural Raceway Habitat Experiment Response variables Growth Health Cryptic coloration Brain development Predation bioassay Instream survival Smolt-to-adult survival

8. Predator Avoidance Conditioning Experiment Rearing treatments No antipredator conditioning Antipredator conditioning Response variables Instream survival Smolt-to-adult survival

9. The effects of NATURES rearing environments on ecological interactions between naturally and hatchery-reared steelhead (Obj. 3 & 4). Rationale: Ecological interactions between wild and hatchery-reared salmonids have been implicated in stock declines. NATURES rearing affects competitive ability and agonistic behavior (Berejikian et al. 2000, 2001).

10. Experimental Facilities Quasi-natural stream (40 x 6 m) Behavior observation flumes

11. How do hatchery rearing environment and stocking density affect interactions with naturally-reared steelhead parr? Stock conventional and NATURES steelhead parr at different densities with naturally-reared steelhead and chinook parr. Evaluate habitat use, agonistic behavior, feeding, growth, survival, and dispersal of naturally- reared steelhead parr.

12. Expected Results Determine the combination of seminatural raceway habitat components that maximize smolt-to-adult survival. Determine if predator avoidance conditioning increases smolt-to-adult survival. Quantify effects of NATURES-reared steelhead on the growth, survival, and dispersal of natural steelhead and chinook parr. Quantify effects of NATURES-reared steelhead on the habitat use, behavior, and feeding of natural steelhead and chinook parr.