Welcome to the Tobin
Disturbance Ecology

Patrick Tobin
People in the Lab


Jake Betzen
is investigating the extent and severity of a recently reported decline in bigleaf maple in the urban and suburban forests of Western Washington. Bigleaf maple is a prominent component of the urban and suburban landscape in Western Washington. In heavily populated areas of Western Washington, it also is one of the few tree species seemingly able to support the regionís iconic epiphytes, which contribute to a number of important and diverse ecosystem services. Jake earned his B.S. from Colorado State University.

Michael Bradshaw
studies the evolution of plant resistance to insect and pathogenic fungi in a variety of systems. The overarching goal of his research is to examine the relationship between host divergence and susceptibility. Michael has a keen interest in ornamental horticulture where non-native organisms have been found to cause substantial economic losses to the industry. Michael received a B.S. from the University of Delaware and a M.S. from the University of Washington studying powdery mildew.

Sean Callahan studies the effect of vehicular pollution on the regionís iconic epiphytes and the communities they support. Population growth in the region is a major issue, and the expanding transportation sector represents a significant source of pollution. Epiphytes and the communities they support contribute to a number of ecosystem services, including intercepting atmospheric pollution. Seanís research aims to document and quantify pollution impacts to the regionís epiphyte communities under projected changes in climate. Sean earned his B.S. from Cornell University.

Michael Freeman is working to quantify the factors that affect Douglas-fir mortality in the Cedar River municipal watershed. Mortality rates in conifer forests of the western United States are believed to be increasing, and Michael is working to identify the role that insects and pathogens are playing in causing higher than historically-expected rates of Douglas-fir mortality in the Cedar River municipal watershed, which supplies clean drinking water to over a million people in the greater Seattle area. Michael earned his B.S. from Eckerd College.

Ryan Garrison
is interested in the dynamics and management of the Azalea lace bug in Western Washington. This invasive species, which is native to Asia, was detected in the Pacific Northwest in 2008, and it is causing region-wide mortality to azaleas. At particular risk are those azaleas planted along Azalea Way, which was established in the 1930s, at the Washington Park Arboretum. Ryan earned his B.S. from Michigan State University.

Riley Metz is working to identify the forest conditions that are most conducive to the success of the gypsy moth. The gypsy moth is a notorious non-native species that has been recently detected in Western Washington, leading to several eradication programs around Washington in 2016. Riley is working to identify the key factors that affect gypsy moth establishment and population growth, which will help prioritize management decisions, optimize sampling protocols, and help keep the regionís forests free of this invasive species. Riley earned her B.S. from Albright College.

Alex Pane
is broadly interested in investigating the interaction of biotic and abiotic disturbance of Western Washington forests in light of the changing climate. The Douglas Fir-Western Hemlock forests of Western Washington are historically characterized by infrequent severe wildfires and relatively low numbers of insect outbreaks, but longer summers mixed with below average rainfall are creating stressful conditions that could increase the frequency of these disturbances. Alex's research looks to unravel these interacting processes to develop models that can more accurately predict these disturbances as the climate continues to change. Alex earned his B.S. from the University of Illinois.

Lila Westreich is interested in pollinator ecology, specifically the developmental effects of non-native plant pollen on native bee species of the Pacific Northwest. The introduction of non-native species can have a direct and cascading effect on the function and structure of native ecosystems. Insect pollinators search among angiosperms to find the most nutritionally sufficient food sources for their offspring, and the effect of pollen from non-native plant species on pollinator colony fitness is not well understood. Lila is working to identify the key factors affecting mason and leafcutter bees across Seattle, as well as native restored and non-native areas, including those affecting emergence. Bee pollinators, especially native species, are increasingly important as other pollinator species are shown to be in decline. Lila earned her B.S. from the University of Minnesota.

Kjaisa Gifford is a UW senior majoring in Environmental Science Resource Management. As part of her senior capstone project, Kjaisa is interested in the role that climate change could play in altering plant-insect interactions.

Postodoctoral Researchers
Dr. Angela Mech (2016-2017)
Primary project: Predicting the next high-impact insect invasion: Elucidating traits and factors determining the risk of introduced herbivorous insects on North American native plants

Graduate Students
Marisa Bass, Master of Forest Resources (2016)
Thesis title: Comprehensive five-year harvest and transportation plan for Hancock Forest Management's Tahoma Client

Undergraduate Students

Ceci Henderson,
Senior Thesis (2017)
Project title: The Grapes of Wrath: Invasion potential of Lobesia botrana (European grapevine moth) in Washington State vineyards under varying climate change scenarios
Grace Masaoka, Senior Capstone Project (2017)
Project title: Investigation of the western sword fern disappearance in Seward Park
Constance Lin, Senior Capstone Project (2016)
Project title: Microarthropod species richness and abundance in epiphytic communities along an urban to wildland gradient in Western Washington
Rachel DeCordoba, Senior Thesis (2016)
Project title: Spatial and climate analysis of bigleaf maple decline in Western Washington
Alex Blumenfeld, Senior Capstone Project (2016)
Project title: Modelling the drivers of invasion in North American non-native insects
Kaitlin Stair,
Senior Capstone Project (2015)
Project title: Consumptive and non-consumptive effects of a generalist predator on larval prey growth