Relative growth and survival of offspring from matings of hatchery and wild Deschutes River (Oregon) summer steelhead trout, Salmo gairdneri, were monitored to determine if hatchery fish differ genetically from wild fish in traits which can affect the stock-recruitment relationship of wild populations. Four natural streams and a hatchery pond...
The merits of fertilizing warmwater fish ponds with dry organic manure were studied from October, 1964 to November, 1965 using two experimental ponds in the Willamette Valley. One pond (pond II) was fertilized with urea and single superphosphate and the other (pond III) was fertilized with dried manure as well...
A study designed to evaluate the use of floating cages for rearing fingerling and subadult channel catfish (Ictalurus punctatus) and fingerling brown bullheads (I. nebulosus) on a commercial basis in Oregon's Willamette Valley was conducted at a pond seven miles north of Corvallis, Oregon, from May 23 to October 17,...
Juvenile coho salmon (Oncorhynchus kisutch (Walbaum)) and aquatic invertebrates were subjected to experimentally increased, but naturally fluctuating, temperatures in a model stream channel. Coho of the 1969, 1970, and 1971 year classes were reared in the heated model stream and in an unheated control stream, both located at the Oak...
Fishery researchers have attempted to preserve viable fish sperm for extended periods of time. Only limited success has been achieved with storage of spermatozoa from salmonids. The principal accomplishments of this investigation during the fiscal year 1966-1967 were the development of standard methods for the collection
and evaluation of fish...
The objectives of this study were to determine whether changes in
the selective pressures which occur in a hatchery could cause inherited
modifications in the behavior of steelhead trout (Salmo gairdneri) that
would affect their survival in the wild. Environmental effects on the
behavior of the offspring of hatchery and...
