We investigated ontogenetic changes in body morphology of Weddell seals (Leptonychotes weddellii) using three three-dimensional (3D) photogrammetry, to estimate surface areas and body volumes for 42 Weddell seals. We sampled ten weaned pups, twelve juveniles (age one or two years), 11 non-breeding adult females, and 9 adult females who had...
Biodiesel is a renewable, non-toxic, and biodegradable diesel fuel made from agricultural feedstocks. With a vibrant agricultural industry, Oregon is positioned to play an important role in the future of this energy source. Limiting factors to widespread biodiesel production include low value of biodiesel feedstock crops, lack of infrastructure, lagging...
Accurate estimation of water stress in vineyards could prove vital for optimizing irrigation and grape quality in a changing climate. The ECOsystem Spaceborne Thermal Radiometer Experiment on the Space Station (ECOSTRESS) offers potential to remotely sense vineyard water stress but lacks validation against in-field measurements in vineyards. In this study,...
Bee populations are declining around the globe, while the need for their pollination services is increasing with growing food demands by an expanding population. There is a need for innovative practices to increase pollination in agricultural environments without harming wild bee populations. However, the use of artificial visual attractants has...
The Oregon chub (Oregonichthys crameri) is a small minnow (Family: Cyprinidae) endemic to Oregon’s Willamette Valley. In 1993, the Oregon chub was listed as endangered because of habitat loss and predation and competition by nonnative fishes. Conservation efforts by the Oregon Department of Fish and Wildlife (ODFW) and other agencies...
Investigating the insectivorous diet of the Trowbridge’s shrew (Sorex trowbridgii) across forest types can illustrate how forest management affects biotic communities. I used DNA metabarcoding methods with ANML primers to identify stomach and intestines contents from shrews caught in pitfall traps in the HJ Andrews Experimental Forest (HJA) and Willamette...
Millions of acres of rangeland in the western U.S. is shared habitat by elk (Cervus canadensis), mule deer (Odocoileus hemionus), and cattle (Bos taurus). Potential competition between these ungulates for the same forage species can be understood from their diet composition. I used DNA metabarcoding methods with trnL primers to...
Barley yellow dwarf virus (BYDV) is a globally distributed pathogen of grasses that is transmitted by aphids. Little research has been done examining the response of aphids to different host grasses in naturally mixed communities. We measured the short-term fecundity of the aphid Rhopalosiphum padi, a widely distributed vector of...
Coastal Douglas-fir (Pseudotsuga menziesii var. menziesii), a keystone species in the Pacific Northwest, relies on symbioses with microorganisms to obtain nutrients, potentially defend against pathogens, and perform a variety of other tasks. Two of the tree’s primary fungal symbionts are foliar epiphytes and endophytes, which reside on the exterior or...
The Oregon Water Atlas is an aggregation and visualization of Oregon’s water data. Multiple government agencies (state and federal) maintain geographic data related to Oregon’s water, and they exist almost exclusively in GIS (geographic information system) formats. Using GIS processing software in conjunction with web design, a wide array of...