The organization of behavioral activities in time is important
to a bird's survival and reproduction. To be successful, either
proximately or ultimately, a bird must apportion its behavior in time
so that it may obtain sufficient energy for maintenance activities and
for such activities as migration and reproduction. The organization...
This study investigated several physiological aspects of the
water economy of the Sage Sparrow, Amphispiza belli nevadensis,as
they relate to the ability of this species to inhabit xeric desert environments.
When maintained in captivity on a dry diet without
drinking water, Sage Sparrows gradually lost weight and died. During the...
The adaptiveness of polygyny in passerines poses a particularly
intriguing problem. The altricial young of this group require extended
parental care, but young of polygynous pairings generally lack the undivided
attention of the male which young of monogamous pairings receive.
Polygynous offspring may thus be undernourished and experience
The avifaunal composition of ten western Oregon forest stands located at the eastern base of the Coast Range was examined on a seasonal basis. The stands were dominated by Oregon white oak, Douglas fir or western hemlock, Avian populations were sampled monthly from January 1968 to January 1970, using permanent...
The pea crab Fabia subquadrata is frequently found as a symbiont
of mussels, living within the mantle cavity. This study examined
the nature of this symbiotic relationship by recording the pattern
of distribution of individuals in a mussel bed, testing responsiveness
to host secretions, and observing the feeding mechanics and...
The songs of the Bewick's Wren are discrete units of one to three
seconds duration with intersong intervals several times the length of
the song. Individual song repertoires at the William Finley National
Wildlife Refuge, Oregon, range from 13 to 20 song types, and a given
song type is repeated...
During 1969-1971 I studied patterns of resource allocation and
behavioral interaction among Brandt's Cormorants, Pelagic Cormorants,
Common Murres and Pigeon Guillemots in the area of a breeding
colony on Yaquina Head on the central Oregon coast. Extensive studies
of the breeding colony were combined with detailed observations of the
The heat exchange of individuals in a foraging mixed population
of Zonotrichia leucophrys and Zonotrichia atricapilla in western
Oregon is analyzed with respect to the direction of stance and
feeding location. Values for heat gain or loss in the field were
generated from a model that estimates the equivalent black-body...