SEFS Alumnus Aaron Johnston Awarded Mendenhall Fellowship

Aaron Johnston, who earned his Ph.D. from SEFS in spring 2013, was recently awarded a prestigious, two-year postdoctoral research position with the U.S Geological Survey’s Mendenhall Research Fellowship Program! Johnston studied competition between eastern and western gray squirrels in the Puget Sound lowlands for his dissertation (working with Professor Emeritus Steve West), and he will be moving to Bozeman, Mont., after the winter holidays to begin the fellowship.

Aaron Johnston

Aaron Johnston’s fellowship will include two field seasons, and he’ll be expected to produce several publications from the research.

Selected through a competitive proposal process, Mendenhall Fellows help USGS staff conduct concentrated research around a number of important areas. Johnston’s proposal, “Extinction dynamics and microrefugia of the American pika,” will pair him with Dr. Erik Beever in Bozeman to explore the effects of climate change on pikas in the Cascades and Northern Rockies, though he hasn’t finalized his study area yet. He’ll have a research budget and be able to bring on a couple assistants to help with the project.

American pikas (Ochotona princeps) are a smaller relative of rabbits and hares. They’re an herbivorous alpine species that spread south with the last ice age, and now they’re holding on in high-altitude mountain areas in western North America. Their dependence on colder temperatures and preferred habitat—talus fields and rock piles at or above the tree line—has generally restricted their range to “sky islands” at the tops of mountains, where movement from one region to another can’t happen quickly, if at all. As a result, a warming climate threatens to shrink or eliminate the habitable range of pikas in the coming decades, and some estimates already suggest that 40 percent of American pikas in the Great Basin have disappeared in the last century, with the remaining populations retreating to even higher elevations.

Aaron Johnston

With their habitat shrinking as the climate warms, American pikas are retreating to higher elevations on the “sky islands” of mountaintops.

Johnston says there are competing hypotheses about why this large-scale extinction is occurring. One widely supported theory revolves around the fact that pikas can’t survive prolonged exposure to high temperatures (more than a couple hours above 80 degrees, in fact, can kill them). Yet in a few regions, where temperatures far exceed that maximum—such as Craters of the Moon and Lava Beds national monuments—some pika populations have found a way to survive using microrefugia to escape the heat. Other hypotheses focus on phenology, and whether changing temperatures will reduce available vegetation for pikas, or if warmer winters will reduce available snowpack for insulation and expose pikas to extreme cold.

To address these questions and help design effective conservation strategies, Johnston’s project will involve modeling and mapping pika habitat topography using LiDAR. He’s been working in Professor Monika Moskal’s Remote Sensing and Geospatial Analysis Lab, and he sees powerful applications of LiDAR for wildlife management. “I think it’s a really exciting new technology that has enormous potential we’re just starting to realize,” says Johnston.

Project Summary
The objectives of this study are to:

1. Develop broad-scale maps of talus at high-resolution through fusion of LiDAR and multispectral imagery;
2. Develop predictor variables for untested hypotheses about substrate, snowpack and phenology;
3. Evaluate regional variation in extinction mechanisms by incorporating new data on extirpations outside of the Great Basin; and
4. Evaluate differences in habitat and connectivity maps created by models with and without microclimate and microhabitat variables.

This project will use limited field work to characterize substrate at selected sites for development of talus maps, and supplement existing data on pika persistence at historical sites of occurrence. Results of this study will increase understanding of pika responses to climate change, inform conservation strategies, and provide map products widely applicable to many research areas, including wildlife ecology, plant ecology, geomorphology, hazard assessment and hydrology.


Congratulations, Aaron, and good luck with this tremendous opportunity!

Photo of Johnston © Aaron Johnston; photo of pika © Justin Johnsen.

New Faculty Intro: David Butman

Professor David Butman, one of three new faculty members with the School of Environmental and Forest Sciences (SEFS), has been on campus a few weeks now, and he and his family are settling into their new city and neighborhood in Maple Leaf. Like Professor Patrick Tobin, who relocated from West Virginia, Professor Butman comes to us from across the country at Yale University, where he was working as a postdoctoral associate.

David Butman

Perhaps the easiest part about moving across the country to Seattle? Butman, who grew up in a fishing community, will still have tremendous access to water!

New England has been home to Butman for most of his life. He grew up in the historical fishing community of Gloucester, Mass., where most of his family still lives. (His first job out of undergrad, in fact, was working on a commercial fishing boat as an observer with the National Marine Fisheries Service to monitor bycatch for the Marine Mammal Protection Act.) He earned a bachelor’s in economics and environmental studies from Connecticut College, a master’s in environmental science from Yale, and then his Ph.D. in forestry and environmental studies from Yale in 2011.

Switching oceans and coasts, Butman joins us as part of a cluster hire in freshwater science, and he holds a joint professorship with Civil and Environmental Engineering (CEE) and SEFS—though his office is based in our school. The vision for the Freshwater Initiative involves interdisciplinary collaboration across a number of programs and units in the College of the Environment, including CEE and SEFS, as well as the School of Aquatic and Fishery Sciences and UW Tacoma. Among the initiative’s research themes are ecohydrology, watershed ecology and river restoration, fluvial geomorphology, urban water quality, aquatic biogeochemistry and continental hydrology.

David Butman

Butman already has a few projects in the works, including a collaboration with Professor Christian Torgersen out on the Olympic Peninsula.

As part of this broader freshwater research portfolio, Butman brings a strong background in aquatic biogeochemistry and remote sensing, including the application of new sensors to monitor the environment. He studies the influence of humans and climate on carbon cycling at the intersection of terrestrial and aquatic systems. Specifically, he measures the capacity of ecosystems to change as a result of anthropogenic carbon emissions; human landscape alteration, like logging or development; and the effects of climate change, in order to identify environmental stressors within watersheds and mitigate long-term resource degradation.

Butman already has a few projects ramping up, including one down on the Columbia River to measure carbon cycling around The Dalles Dam. He’s been working closely with the Army Corps of Engineers, and he’s looking to expand the project and do more field work over the next couple summers. Also, in collaboration with Professor Christian Torgersen, he’s secured funding for a student to do carbon sampling in the Sol Duc River out on the Olympic Peninsula.

As he gets his research and lab up and running, Butman will likely start teaching this winter or spring, including the possibility of a remote sensing survey course. We’re extremely excited to have him and his expertise as part of the SEFS community, and we hope you’ll introduce yourselves as soon as you can. You can reach Butman by email or stop by his office in BLD 264 (though we’re still working on his nameplate!).

Welcome, David!

Photos © David Butman.

David Butman