The Goose Lake Basin, situated on the border of Oregon and California, USA, faces significant challenges from drought, wildfire, and other environmental stressors. This region hosts numerous endemic fish species such as the Goose Lake redband trout (Oncorhynchus mykiss newberri), Goose Lake lamprey (Entosphenus sp.), Goose Lake tui chub (Siphateles...
Two ecologically important lamprey species found in the endorheic Goose Lake Basin face conservation threats; however, relatively little is known about their habitat needs or spatial distribution. Lamprey and their habitat are often found to be patchy; to evaluate these relationships for the lamprey in this basin, I utilized a...
The California Current Large Marine Ecosystem (CCLME), located on the eastern boundary of the North Pacific Ocean, is highly dynamic, with variable conditions driven by seasonal upwelling, regional oceanography, and broad scale climate patterns. In the last decade, the northeast Pacific Ocean has experienced several marine heatwaves (MHWs), prolonged periods...
Devaleraea mollis (Pacific Dulse) is becoming a popular food for human consumption. Previously, Pacific Dulse has been used as a nutrient source for cultured abalone species, with some historical food use by indigenous peoples, while the closely related Atlantic dulse (Palmaria palmata) has a long-documented history of use in cuisine...
It is well documented that microplastics and semi-synthetic particles (<5 mm) pervade the marine environment, with their ingestion by marine fauna eliciting global concern. While fishes exposed to microparticles in a laboratory setting have exhibited both sub-lethal and lethal effects, the diversity in material, morphology, and size of these contaminants...
Standard larval Pacific oyster (Crassostrea gigas) rearing systems can be described as either static or continuous flow. While rearing oyster larvae in static cultures can be a low-cost and simple method, static systems require significant husbandry effort, floorspace and can produce highly variable results due to environmental variance among cultures....
Streams across the western United States are impaired from human alterations that have reduced freshwater habitat by simplifying channel complexity and disconnecting floodplains (Knox et al., 2022; Waples et al., 2008; Wohl, 2014). Climate change is likely to continue exacerbating these risks by warming summer surface stream temperatures (Crozier et...
Our understanding of seasonally disconnected floodplains and how they function to support rearing salmonids in the Pacific Northwest is limited. Past studies have found that these dynamic habitats may provide high-risk, high-reward trade-offs for rearing fish. High prey densities and optimal temperatures allow for accelerated growth, but low water levels...
The freshwater copepod Salmincola californiensis is an ectoparasite of Pacific salmonids (Oncorhynchus spp.) Threatened and endangered salmonids that rear in the reservoirs have been reported to experience higher rates of infection by S. californiensis than would be experienced by their stream-reared counterparts. These high levels of infection can lead to...
Connectivity of fish populations is a crucial question for fisheries conservation and the development of spatial management plans. Both adult and larval movement define the extent and direction of ecological and evolutionary overlap between geographic regions and, therefore, how we define stocks for management purposes. Within that context, my work...
Juvenile Chinook Salmon (Oncorhynchus tshawytscha) leave the natal reach at different times and move downstream at different rates which can increase their productivity by allowing them to utilize habitats on different temporal scales and spreading risk of localized stochastic events. This life history diversity can also allow fish to adapt...
Annual rates of prespawn mortality (PSM) in adult Chinook salmon (Oncorhynchus tshawytscha) trapped and transported upstream of dams in the Willamette River basin are high (often >40%) and could limit the ability to restore natural populations of spring Chinook salmon if not reduced. Improvements at the U.S. Army Corps of...
Once abundant in their native range, Pacific salmon species (Oncorhynchus spp.) were widely distributed across the northern Pacific Rim from South Korea and Japan to the Sacramento River in California. Remaining populations are subject to population-level threats, including pathogens. The freshwater parasitic copepod Salmincola californiensis is associated with the reduced...
In recent years, there has been an increase in episodic coastal hypoxia along the mid to inner-shelf waters off the Oregon Coast. Wind-driven coastal upwelling events can exacerbate the magnitude of these hypoxic events, causing extremely hypoxic bottom water (<0.5ml l-1 dissolved oxygen) to move onshore towards the inner shelf....
Bioturbation caused by ghost shrimp, Neotrypaea californiensis, burrowing activity can negatively affect Pacific oyster, Crassostrea gigas, aquaculture through their burial and subsequent suffocation. The shellfish aquaculture industry used chemicals to control burrowing shrimp populations in Washington State estuaries for decades, but, due to public and governmental scrutiny, that practice has...
Food webs are fundamental in ecology, as they offer a way to better understand the interrelatedness, connectivity, and complexity within a given ecosystem. The use of network analysis to model food webs can provide insights about the importance of physical templates on the organization of biological systems in streams using...
Headwater streams in the Oregon Coastal Range are subject to drastic fluctuations in flow and temperature because of the changing seasonality of a Mediterranean climate. In response to these changes, stream fishes exhibit a variety of movement patterns. Coastal Cutthroat Trout (Oncorhynchus clarkii clarkii) have evolved an assortment of life...
Contemporary stream restoration efforts increasingly prioritize restoring natural stream processes to regain lost ecosystem functions. Stage 0 stream restoration resets disturbed, channelized streams to a theoretical pre-disturbance state (“stage zero”). It is assumed that this valley-scale restoration/disturbance will restore natural abiotic and biotic processes, leading to greater primary and secondary...
Fisheries managers often use models of population density to evaluate the status of stream-living fishes, but many of these models have low predictive performance for abundance and density. These models could incorporate several factors that can limit population density, particularly the effect of body size, envisioned by the theory of...
The introduction of non-native species can negatively impact native species through reduced genetic fitness resulting from hybridization. The lack of spatiotemporal data of hybrids occurrences makes assessing hybridization risk difficult. Here, I developed a spatially-explicit GIS Hybridization Risk Model (HRM) between native ESA-listed Bull Trout and introduced Brook Trout by...