Casey L Brown

• PhD Biology
• Researcher at State of Oregon

In the western United States, ecosystems are being reshaped from both bottom-up and top-down processes. Widespread carnivore recolonizations after 20 th century extirpations have returned top-down pressures to ecosystems, and climate change is reshaping bottom-up forces through shifts in the timing and length of growing seasons, resulting in reduce...

Recovered and recovering carnivore populations in Europe and North America can pose risks to some human livelihoods like livestock ranching. These risks can motivate wildlife managers to lethally remove carnivores—decisions that are often controversial and poorly understood. We used a 13-year dataset on gray wolves (Canis lupus) in the northwestern...

Drones, or unoccupied aircraft systems (UAS), can transform the way scientific information on wildlife populations is collected. UAS surveys produce accurate estimates of ground-nesting seabirds and a variety of waterbirds, but few studies have examined the trade-offs of this methodology for counting cliff-nesting seabirds. In this study, we examin...

Consistent with a warming climate, the timing of key phenological phases (i.e., phenophases) for many plant species is shifting, but the direction and extent of these shifts remain unclear. For large herbivores such as ungulates, altered plant phenology can have important nutritional and demographic consequences. We used two multi-year datasets col...

Consistent with a warming climate, the timing of key phenological phases (i.e. phenophases) for many plant species is shifting, but the direction and extent of these shifts remain unclear. For large herbivores such as ungulates, altered plant phenology can have important nutritional and demographic consequences. We used two multi-year datasets coll...

Prey respond to predation risk with a range of behavioral tactics that can vary based on space use and hunting mode of the predator. Unlike other predators, human hunters are often more spatially and temporally restricted, which creates a period of short-duration, high-intensity predation risk for prey. Consequently , identifying the roles differen...

Changing biophysical conditions due to amplified climate change in northern latitudes has significant implications for species' habitat and populations and can dramatically alter interactions between harvesters and local resources. Tribal, regional, and state governments, federal agencies, and other local planning entities have begun documenting ob...

Characterizing the habitat associated with predation events can inform on predator-prey dynamics. Despite being evaluated extensively in terrestrial systems, quantifying and characterizing the role predation plays in upper trophic marine ecosystems is challenging due to the cryptic nature of pelagic predators and the difficulty of observing predato...

Mule deer (Odocoileus hemionus ) are widely hunted throughout western North America and are experiencing population declines across much of their range. Consequently, understanding the direct and indirect effects of hunting is important for management of mule deer populations. Managers can influence deer mortality rates through changes in hunting s...

Understanding linkages between behaviors and mortality risk is critical for managing populations. Juveniles constitute a particularly vulnerable life stage, with growing evidence that within stages, individual strategies may be associated with greater predation risk and mortality. These forms of predator-prey dynamics are rarely explored in marine...

The life-and-death stakes of predator-prey encounters justify the high price of many anti-predator behaviors. In adopting these behaviors, prey incur substantial non-consumptive costs that can have population-level consequences. Because prey knowledge of risk is imperfect, individuals may even adopt these costly behaviors in the absence of a real t...

Background Recent advances in satellite tagging technologies for marine animals have provided opportunities to investigate the spatial ecology of pelagic species including at-sea behavior and predator–prey interactions. Implantable Life History Transmitters (LHX tags) provide postmortem data on location and causes of mortalities from tagged individ...

Many rural communities are increasingly relying on off‐road motorized vehicles to access wildlife for both subsistence harvest and recreational hunting. Understanding the effects of trail and road networks on wildlife behavior is crucial to effective management for subsistence opportunities in communities that depend on accessible populations as an...

Background A utilization distribution quantifies the temporal and spatial probability of space use for individuals or populations. These patterns in movement arise from individuals’ internal state and from their response to the external environment, and thus can provide insights for assessing factors associated with the management of threatened pop...

The functional response is the relationship between food intake rates and prey density, and is shaped by factors including handling time, predator speed, habitat or prey movement. For many predator—prey systems, the density-dependent functional response is represented by a type II or type III functional response. Determination of the relationship t...

Fire severity is an important control over regeneration of deciduous species and can influence the overall quality of habitat for herbivores, such as moose (Alces alces (Linnaeus, 1758)), but the relationships between availability and duration of biomass production and moose habitat use are largely unknown. We evaluate the relative influence of a r...

Unmanned aircraft systems (UAS) - also called unmanned aerial vehicles (UAVs) or drones - are an emerging tool that may provide a safer, more cost-effective, and quieter alternative to traditional research methods. We review examples where UAS have been used to document wildlife abundance, behavior, and habitat, and illustrate the strengths and wea...

Central America is home to some of the world’s most diverse landscapes including at least 20 life zones, 22 ecoregions, and five major tropical forest types (Holdridge et al. 1971). As a constricted, natural corridor between North and South America, Central America hosts a variety of mammalian species from both continents, and is also home to sever...

We investigated wildfire-related effects on a slow ecological variable, i.e., forage production, and fast social-ecological variables, i.e., seasonal harvest rates, hunter access, and forage offtake, in a moose–hunter system in interior Alaska. In a 1994 burn, average forage production increased slightly (5%) between 2007 and 2013; however, the pro...

Noise emanating from human activity has become a common addition to natural soundscapes and has the potential to harm wildlife and erode human enjoyment of nature. In particular, motor vehicles traveling along roads and trails produce high levels of both chronic and intermittent noise, eliciting varied responses from a wide range of animal species....

The effect of anthropogenic noise on terrestrial wildlife is a relatively new area of study with broad ranging management implications. Noise has been identified as a disturbance that has the potential to induce behavioral responses in animals similar to those associated with predation risk. This study investigated potential impacts of a variety of...

Anthropogenic noise is a burgeoning issue for national parks. Acoustical monitoring has revealed chronic noise exposure even in remote wilderness sites. Increased noise levels significantly reduce the distance and area over which acoustic signals can be sensed by an animal receiver. A broad range of research findings indicates the potential severit...