Dwelling on the bottom of large rivers to high alpine streams, freshwater sculpins (genus Cottus) occur in high densities across the Pacific Northwest, with 21 currently recognized species found in the Pacific Northwest. Sculpin fill many ecological roles, with some species serving as important prey sources, and others competing with...
Accumulating human impacts on freshwater ecosystems have created a biodiversity crisis for freshwater fishes while conservation efficacy remains hampered by the Linnaean shortfall, the ignorance of many species that have yet to be discovered and described. The past discovery of most freshwater fish species was simply a matter of collecting...
Social behavior leading to the production of common goods is prone to exploitation. One such behavior in Pseudomonas aeruginosa is quorum sensing (QS), by which the bacteria produce signals to regulate extracellular common goods. Exploitation comes in the form of cheaters which have a mutation in the central quorum sensing...
Black vine weevil (BVW), Otiorhynchus sulcatus Fabricius, is a serious pest in cranberry, Vaccinium macrocarpon. Larvae feeding below the soil surface cause damage to the roots and underground stems. Knowledge is sparse in regard to the damage potential of BVW in Pacific Northwest cranberry beds. Control with insecticides is limited...
The consequences of species introductions into non-native habitats are a major cause of concern in the U.S. An introduced species may alter native habitats, cause economic damage, compete with natives for resources or prey on them. Of particular interest are the effects of predation by introduced fishes on native amphibians....
Cancer is one of the leading causes of death in the U.S., and new approaches to control cancer are constantly sought. This dissertation is comprised of two parts: (i) improving the uptake and retention of gadolinium in tumors for potential gadoliniumneutron capture therapy (Gd-NCT) and (ii) integration of gemcitabine or...
This study was undertaken to determine if strontium chloride could be used to create a trans-generational otolith mark in steelhead (Oncorhynchus mykiss). I completed two strontium injection trials and a survey of juvenile steelhead from various steelhead hatcheries. The two trials measured Sr:Ca ratios in otoliths in response to injections...
Mark-recapture methods were used to examine watershed-scale survival rates of coastal cutthroat trout (Oncorhynchus clarkii clarkii) from two headwater stream networks located in the foothills of the Cascade Mountain Range, Oregon. Differences in survival were explored among spatial (stream segment, stream network [main stem or tributaries], and watershed) and temporal...
Wildfire is a largely terrestrial perturbation broadly recognized as an agent of disturbance and ecological change in forested biomes. Effects of post-fire conditions on biotic components of aquatic systems have been less well-documented, although hypothetically, the two are strongly connected. In fact, the influence of wildfire may be most profound...
Giant otters (Pteronura brasiliensis) and humans in the Lower Yasuní Basin (Ecuador) have similar food and space requirements: they consume comparable arrays of fish species, and they use similar aquatic and terrestrial habitats. Resource partitioning could facilitate coexistence by allowing each species exclusive access to some resources.
My research examines...