The Burning Question What information do we have available to use to set an escapement goal for steelhead if current models give results that are constrained by the fishery previously imposed on the stock?
Steelhead Parr per metre in Treatment and Control Habitats Greatest effect came from combined treatment of structures and nutrient enrichment. It is essentially additive.
Effect of nutrient addition on Keogh steelhead smolt ages
KEOGH RIVER Approximately 259,000 sq m surface area Loaded with equivalent of 64,260 kg carcasses, in addition to 50,000 pinks every other year Approx biomass loading of 0.63 kg/ sq m Soos Cr, a Green R. trib, has 249,000 sq m (96% of Keogh) Skagit R has 21,129,900 sq m (81.6 times larger than Keogh)
SOOS CREEK I Small stream, tributary to Green River with a hatchery and rack near mouth For 1981-2002, Chinook and coho passed upstream have averaged 0.14 kg per square metre; maximum in 2000 of 0.63
SKAGIT RIVER Surface area of streams accessible to coho is 81.6 times as large as Keogh River. If Keogh averages 50,000 pink, a simple expansion gives 4,080,000 pinks for the Skagit Current goal for Skagit pink is 330,000
UPSHOT Nutrients, as delivered by spawning salmon, are critical Quality habitat, including appropriate flows, access to stream reaches, habitat complexity, are equally critical
STEELHEAD ESCAPEMENT GOAL Harvest rate on wild stock no more than 10% in total. Coho escapement target of at least 0.15 kg per square metre Pink escapement goal of at least 0.63 kg per square metre Chum escapement goal of 0.5 kg/square metre Fall Chinook escapement goal of 0.63 kg per square metre to match pinks Spring Chinook goal of 0.15 kg per square metre to match coho
SOOS CREEK ESCAPMENT GOAL For Chinook (7.97 kg) and chum (4 kg), target only the mainstem of Big Soos Cr, 104,479 square metres For coho (2.27 kg) use entire basin, 249,057 square metres Chinook=8,250 Chum=16,450 Coho=16,450