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California Department of Fish and Wildlife's Trinity River Project conducted tagging and recapture operations from June 2015 through March 2016 to produce run-size, angler harvest, and spawner escapement estimates of spring- and fall-run Chinook salmon (Oncorhynchus tshawytscha)], coho salmon (O. kisutch), and fall steelhead (O. mykiss) in the Trinity River basin. Monitoring results informs the Trinity River Restoration Program’s (TRRP) adaptive management decision making process and helps evaluate progress toward achieving fundamental objectives outlined in the Integrated Assessment Plan (TRRP, 2009) Using a Petersen mark-recapture methodology, we estimated a run-size of 4,408 (95% CI 3,752 – 5,119) spring-run (spring) Chinook migrated into Trinity River basin upstream of Junction City weir (JCW). The run was comprised of an estimated 1,146 naturallyproduced adults and 177 naturally-produced jacks and 2,772 hatchery-produced adults and 313 hatchery-produced jacks. Using tags returned by anglers we estimate 190 spring Chinook were harvested, yielding an escapement of 4,218 fish. Escapement of 1,090 naturally-produced adult spring Chinook was 18.2% of the TRRP goal of 6,000 spring Chinook. An estimated run-size of 10,365 (95% CI 9,230 – 11,569) fall-run (fall) Chinook migrated past Willow Creek weir (WCW). The run was comprised of an estimated 3,609 naturallyproduced adults and 2,226 naturally-produced jack salmon and 4,006 hatcheryproduced adults and 524 hatchery-produced jacks. We estimate 56 fall Chinook were harvested by anglers, yielding a total escapement of 10,309 fish. Escapement of 3,592 naturally-produced adult fall Chinook was 5.8% of the 62,000 fish TRRP goal. Both coho run-size and escapement in the Trinity above Willow Creek were estimated at 4,619 (95% CI 4,169 – 5,094), because no coho were reported as harvested. Coho escapement was comprised of an estimated 748 naturally-produced adult and 65 naturally-produced jack coho and 2,936 hatchery-produced adult and 870 hatcheryproduced jacks. Escapement of 748 naturally-produced coho adults was 53.4% of the TRRP goal of 1,400 fish. An estimated run-size of 11,167 (95% CI 9,962 – 12,445) adult fall steelhead returned to the Trinity River basin upstream of WCW. Anglers harvested an estimated 436 adult fall steelhead above WCW, leaving 10,732 (2,454 naturally-produced and 8,278 hatchery-produced) fish as potential spawners. Escapement of 2,454 naturallyproduced adult steelhead was 6.1% of the 40,000 fish TRRP goal.