The sinuous flight behavior of male Douglas-fir tussock
moths, Orgyia pseudotsugata, (McD.), is characterized by
positive anemotaxis and positive chemoklinotaxis and varies
depending on distance from the pheromone source, population
density, and time of day. Visual cues play a minor role
in close-range orientation to a pheromone source, but
males...
The seasonal development and habits of Labops hesperius Uhler
were studied in rangeland seeded to intermediate wheatgrass (Agropyron
intermediurn (Host) Beauv. ) in Baker County, Oregon, The
first nymphs appeared on March 22, and required about one week to
complete each of the five nymphal stadia. Most small nymphs stayed...
Reported are results of a study of otolith nuclei as a means to separate juvenile steelhead trout (Salmo gairdneri) from juvenile rainbow trout (S. gairdneri) which co-exist in the lower Deschutes River, Oregon. An intensive recreational fishery necessitated development of a technique for separation so that the impact
of the...
Fresh-water benthic river algae were collected from selected
sites in Willamette River tributaries; two sampling sites were in the
Yamhill River system and four sampling sites were in the Santiam
River system. Twelve samples were taken at each collection site in
the Yamhill River system at approximately monthly intervals from...
Biological attributes and alteration of the habitat of Labops
hesperius Uhler were investigated on rangeland seeded to crested
wheatgrass near Vale, Oregon, and on rangeland seeded to crested
and intermediate wheatgrass near Seneca, Oregon. Nymphs and
adults were present at Vale from late March until mid-June and at
Seneca from...
This study examined the foraminifera and the ecologic conditions
of the benthic environment of the Oregon shelf and the uppermost slope
(75-550 m depth) between 143°45' N and 144°40' N. Seasonal collections
monitored the near-bottom marine environment and the sedimentary
substrate at 16 stations. The foraminiferal benthic fauna was
examined...