Through key regional collaborations with the Pacific States Marine Fisheries Commission, Oregon Department of Fish and Wildlife, Alaska Fisheries Science Center, and the fishing industry, the Marine Habitat Ecology Team at the NWFSC has been able to pursue a wide-ranging array of conservation engineering projects relevant to reducing bycatch in the west coast groundfish and ocean shrimp trawl fisheries. Examples of types of research projects pursued during any given year include: 1) Reducing Chinook salmon, eulachon, rockfish, and Pacific halibut bycatch in midwater and bottom trawl fisheries using Bycatch Reduction Devices (BRDs), 2) Examining selectivity characteristics of codends that differ in mesh size and configuration in bottom trawl fisheries, and 3) Testing other novel bycatch engineering modifications to mobile and fixed gears. Much of our current work has been in response to the fishing industries concerns over catches of overfished and rebuilding rockfishes and Pacific halibut allocated in the Pacific coast Groundfish Trawl Rationalization Catch Share Program. The trawl rationalization program, starting in January 2011, established formal Annual Catch Limits (ACLs) and individual catch share quotas. In addition to ACLs, fishing opportunities may also be limited by hard caps or IBQs for non-groundfish species (e.g., Chinook salmon, and Pacific halibut). Bycatch of overfished and prohibited species in the west coast groundfish trawl fishery has the potential to constrain the fishery such that a substantial portion of available harvest may be left in the ocean. Temperature and light radiance.