Spawning fall Chinook and coho salmon were counted. Statistics give historic counts. Less area was surveyed in 1975, and methods of data analysis were re-evaluated.
The fall chinook index of abundance was 128% of the long-term average, and presumably would have been even higher had survey conditions in the central and north coast not been so difficult.
The surveys of spawning fish in coastal rivers in 1971 indicate that stocks of chum salmon remain at a low, although apparently stabilized level. Fluctuations are probably the result of year-class survival and age at maturity, rather than continued decline of the species.
The fall chinook index of abundance was...
Spawning coho, chinook, and chum salmon are annually surveyed in coastal streams by Department of Fish and Wildlife personnel. Annual peak counts of spawning salmon provide data for computing an index of coastal escapement which is plotted each year to chart spawning salmon trends over a period of years. This...
Artificial propagation has been a prominent part of the management of salmonids in Oregon since the late 1800s, and will continue to have an important role to play in the recovery of wild stocks of anadromous salmonids in Oregon. Hatcheries and reviews of hatchery programs have been controversial and are...
Gives standard spawning data for salmon in Oregon and adds information "to document straying of private hatchery coho salmon from Oregon Aqua-Foods'(OAF) facility at Yaquina Bay. . . The program was conducted in response to concerns by fisheries managers and the public on the possible long-term effects of interbreeding wild...
"Kokanee were originally stocked in Detroit Reservoir in 11959. This species was introduced in hopes that it would utilize pelagic zoo plankton and provide a more varied sport fishery. The trout fishery in the reservoir depends primarily on heavy plants of legal-sized rainbow trout, supplemented by stocking fingerling rainbow. As...
The typical coho salmon life history has been characterized by juvenile fish that spend their entire first year in freshwater habitats before migrating into estuaries as smolts. However, reports of early migrating coho fry (age 0), including migration downstream to estuarine habitats, date back to the 1960s. Until a few...
This report on departmental activities describes "physical stream and lake surveys, spawning fish surveys and individual investigations of particular human activities which might affect the well being of the salmon resource. The advent of federal cooperation has allowed an expansion of activities to include intensive collection of data on streams...
The fitness of female Pacific salmon (Oncorhynchus spp.) with respect to breeding behavior can be partitioned into at least four components: survival to reproduction, competition for breeding sites, success of egg incubation, and suitability of the local environment near breeding sites for early rearing of juveniles. Accordingly, breeding sites should...
Oregon's only remaining non-reservoir population of adfluvial bull trout (Salvelinus confluentus) is found in Odell Lake, in the headwaters of the Deschutes River. The population size is unknown, but appears to be quite small. Limited spawning and rearing habitats, combined with the effects of introduced species and other anthropogenic changes...
Spring chinook salmon, Oncorhynchus tshawytscha, in the Snake River Basin are listed as endangered under the Endangered Species Act. The typical life history of spring chinook salmon is semelparous. An experiment was performed to see if mature male spring chinook salmon parr could be reconditioned after hand-spawning and spawned in...
Chum salmon from different stocks were bred together in two experiments. Three stocks contributed gametes to one experiment, two stocks to another. Sibling groups of eggs, alevins, and fry were maintained in a common environment. Variability of development rates, rearing performance, susceptibility to disease, and behavioral traits was partitioned into...
This study was designed to provide life history information about juvenile fall Chinook salmon, Oncorhynchus tshawytscha
(Walbaum), in a small coastal river by 1) documenting the length of residence of the juveniles throughout the river, 2) exploring several factors possibly influencing their length of residence, and 3) assessing the relative...
Studies were conducted during late winter and spring of 1970 to
establish the extent of spawning of Pacific herring (Clupea harengus
pallasi Valenciennes) in the Yaquina estuary, and to define the degree
of egg mortality on certain substrates. Routine surveillance of the
north shore of the estuary provided information on...