The fishes of Upper Klamath Lake appeared to distribute
themselves in three general groups during the summers of 1964
and 1965: (1) the chubs--unrestricted as to distribution with slight
seasonal variations; (2) rainbow trout and yellow perch -- restricted
to certain water conditions that exist only along the northern marsh...
A study of the population ecology of Columbia River fall chinook
salmon, Oncorhynchus tshawytscha (Walbaum), was made in an attempt
to determine the cause of a serious decline in this run which occurred
in the early 1950's. Fluctuations in abundance of major salmon runs
the North Pacific were examined to...
The effects of sublethal concentrations of kraft mill effluents
(KME) on the growth, food consumption, and swimming ability of
juvenile chinook salmon, Oncorhynchus tschawytscha (Walbaum),
were studied from February 1966 to May, 1967.
The KME used in these studies was obtained from two pulp and
paper mills producing paper from...
Six hundred and forty nutrias, Myocastor coypus (Molina), were collected near Corvallis, Oregon, and examined to determine criteria of their growth and reproduction. Two hundred and eighty-nine
were tagged, measured, and released to determine growth under natural conditions. Nutria weights were calculated to the nearest 0.1 pound by weighing the...
Selection of colored nest boxes by wood ducks (Aix sponsa)
was evaluated during the breeding seasons of 1967-68 in Benton
County, Oregon. No color or site factor influence was observed
in 1967 when nest boxes were erected in sets of eight boxes
served in 1967 when nest boxes were erected...
The abundance and distribution of the Pacific harbor seal
(Phoca vitulina richardi) and the northern or Stellar sea lion (Eumetopias
jubata) in Oregon are described, The number of seals and sea
lions presented for bounty in Oregon since 1925 is presented.
Based on periodic surveys conducted between December, 1967
and...