Minthorn Springs Creek summer juvenile release and adult collection facility (Operation, maintenance and evaluation of the Bonifer and Minthorn Springs juvenile release and adult collection facilities). Annual report, 1990

摘要

The Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and Oregon Department of Fish and Wildlife (ODFW) are cooperating in a joint effort to increase steelhead and re-establish salmon runs in the Umatilla River Basin. As part of this program, Bonifer and Minthorn Acclimation Facilities are operated for holding and spawning adult steelhead and acclimation and release of juvenile salmon and steelhead. A total of 92 adult steelhead were collected for broodstock at Threemile Dam from November, 1989 through April, 1990 and held at Minthorn. Twenty-one pairs were spawned. An additional four pairs were spawned at Threemile Dam. A total of 146,740 eggs were taken and transferred to Irrigon Hatchery for incubation. An estimated 256 adult hatchery steelhead returned to the Umatilla River in 1989--90 and 104 were released upriver. In 1990, 2,190 spring chinook salmon returned to the Umatilla River (based on Threemile Dam trap counts; none were harvested below Threemile Dam) and 1,964 were released upriver. Acclimation of 114,345 spring chinook salmon and 59,747 steelhead was completed at Bonifer in the spring of 1990. At Minthorn 132,404 coho salmon were acclimated and released. Acclimation of 71,864 fall chinook salmon at Minthorn and 80,438 spring chinook salmon at Bonifer was successfully completed in the fall. The progress of outmigration for acclimated releases was monitored at the Westland Canal and Threemile Dam juvenile salmonid traps by CTUIR and ODFW personnel. Because the fish in each release were not uniquely identified, species, marks and lengths were used to discern general trends. The data suggests that salmonids released in the spring migrate downstream quite rapidly. Personnel from the ODFW Eastern Oregon Fish Pathology Laboratory in La Grande took samples of tissue and reproductive fluids from Umatilla River summer steelhead broodstock for monitoring purposes and to certify eggs as pathogen-free. 8 refs., 19 figs., 27 tabs.