Past tracking studies of marine animals have primarily targeted adults, biasing our understanding of at-sea habitat use toward older life stages. Anthropogenic threats persist throughout the at-sea ranges of all life stages and it is therefore of interest to population ecologists and managers alike to understand spatiotemporal distributions and possible...
Native upland prairies, which once dominated the landscape of the Willamette Valley, are considered among the rarest of Oregon's ecosystems. Even though only remnants remain today, they harbor many rare and endangered species such as the Fender's blue butterfly and its host plant, Kincaid’s lupine. Invasion of remnant prairies by...
I conducted 14-22 waterbird and raptor censuses each year from 1992-1995 during late April or early May through October. I observed 44 waterbird and 13 raptor species, including hatch year individuals of seven waterbird species. The records for each census are given.
Active habitat management plays a key role in the preservation of native ecosystems and rare species, especially in the Willamette Valley of Oregon, where natural succession to woodlands threatens the few wetland prairies remaining after 150 years of agriculture and urbanization. Sidalcea nelsoniana, listed as threatened under the federal Endangered...
Wetland prairies of the Willamette Valley, considered among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native species. Because of its historical importance, fire is a top choice of managers for preventing the encroachment of woody species. However, the effects of prescribed burning on present...
Avian movement behavior provides insight on patterns of regional and local fidelity, habitat and resource requirements, the scale at which individuals perceive the landscape, and the relative influence of the spatial array of resources. Shorebirds (suborder: Charadrii) are a diverse and mobile group of wetland associated species. Large numbers of...
Understanding how wetland birds use habitat is pivotal to developing successful and
beneficial conservation strategies. Although it has been an ardent topic in forest
research for some time, how species interact with the spatial patterning of habitat
across a landscape (i.e., landscape structure) has been more or less neglected in...
Adult dusky Canada geese (Branta canadensis
occidentalis Baird) were banded with plastic neck bands and
observed on the winter range during 1985-92. Annual
survival rates of adult geese estimated from observation
data ranged from 76% to 85%. A model of Canada goose
population dynamics was developed to illustrate
relationships between...