Breanna F Powers

Northern Arizona University | NAU · College of Engineering, Forestry, and Natural Sciences

To conserve biological diversity in a changing world, managers must understand which species are vulnerable to the effects of climate change and whether there is sufficient capacity for these species to adapt. This is especially applicable to birds, who may experience changes in phenology (e.g., the timing of migration and/or breeding) in response...

In migratory birds, among‐ and within‐species heterogeneity in response to climate change may be attributed to differences in migration distance and environmental cues that affect timing of arrival at breeding grounds. We used eBird observations and a within‐species comparative approach to examine whether migration distance (with latitude as a prox...

Sustaining ecosystem services (ES) is a key interest in the management of land use in multifunctional landscapes (i.e. ES that support ecosystem function and sustain human livelihoods). In making land management decisions, it is important to understand the relationships and spatial distributions of multiple ES, and the synergies and trade-offs betw...

Premise: Drought-induced tree mortality is an emergent threat to forests worldwide, particularly to large trees. Drought-manipulation experiments involving throughfall exclusion (TFE) tend to focus on large plots that can be expensive to establish and maintain and may be unsuitable for large trees or indigenous forests. We set out to establish a r...

Biodiversity assets often require conservation management, which, in turn, necessitates decisions about which ecosystem, community or species should be prioritised to receive resources. Population viability analysis (PVA) uses a suite of quantitative methods to estimate the likelihood of population decline and extinction for a given species, and ca...

Background/Question/Methods In the Willamette Valley, prairie-oak butterfly species are rapidly declining as a result of loss and degradation of prairie-oak ecosystems upon which these obligate species rely. Butterflies are important for ecosystem integrity because they provide services such as pollination, prey species, and decomposition. The ob...

Great Gray Owls (Strix nebulosa) in the Sierra Nevada Mountains feed primarily on rodents, especially voles and pocket gophers. Voles have been shown to be negatively affected by cattle grazing, but effects of grazing on gophers in the Sierra Nevada Mountains are unknown. We investigated the effects of grazing on pocket gophers (Thomomys monticola...

The aim of the study was to evaluate changes that occurred over time in the composition of the riparian community at the Lone Dome Recreational Area, below McPhee Dam on the Dolores River, Colorado. Cover data for 14 riparian species from a 540 m line-transect were sued to evaluate community composition over time. A Bray-Curtis ordination was used...