9328 - Laserfiche WebLink

Home Browse Search

Oregon has recently taken a major (bold) fishery management step with the adoption of its natural production and wild fish management policy. Oregon's policy states that the maintenance of wild stocks is a biological necessity to insure the future abundance of both naturally and artificially produced runs (Anon. 1990a). Biologists believe that, despite past stocking practices, distinct stocks of wild indigenous fish are still viable. Their managers also state that prior to 1960, the majority of hatchery fish released did not live to reproduce. These failures primarily resulted from improper stocking practices, i.e., time and size at release, poor quality fish and/or stocking fish poorly adapted for the environment (Anon. 1982a). We reviewed 51 projects in Oregon; only 2 were considered supplementation, both were successful. steelhead Endemic runs of summer and winter races of steelhead occur in Oregon. Winter steelhead are primarily coastal, whereas the summer steelhead range encompasses coastal as well as interior streams. Release size for Oregon steelhead smolts is 5-6 fish/lb (60-90 g; 200-215 mm}. Oregon managers note that larger smolts produce greater adult returns. However, it was also noted that larger smolts stray at increased rates. Hatchery philosophy in Oregon over much time (1890-1960) centered around releases of unfed fry and pre-smolts. These hatchery fish were usually superimposed on healthy stocks of natural fish in good habitat with ineffective or counterproductive results (Smith 1.987). Smith (1987) also noted that outplanting unfed fry and short-fed pre-smolts probably presents the highest potential for interference with indigenous fish. Oregon biologists are currently experimenting with sterilization of summer steelhead in the Willamette Subbasin to prevent interaction of hatchery summer steelhead with wild winter steelhead juveniles. The hatchery summers provide a sport fishery while the wild winter run rebuilds.l Coho Coho salmon in Oregon occur primarily in coastal streams and in the Columbia River (lower river tributaries). Based on historical catch records, one can easily deduce that the Columbia River once produced at least as many coho as Oregon coastal streams. 1Ken Kenaston, Oregon Department of Fish and Wildlife, Corvallis, Oregon, pers. comm., April; 1990. 5