About

Patrick C. Tobin is a professor at the School of Environmental and Forest Sciences at the University of Washington. His research focuses on the biology and ecology of biological invasions, the spatial and temporal dynamics of insect populations, and the role of climate change on insect population dynamics. His work includes studying historical insect outbreak dynamics in the Pacific coastal temperate rainforest and testing North American fir species for genetic tolerance and resistance to balsam woolly adelgid. Tobin's expertise encompasses invasive species ecology and management, landscape ecology, and statistics, spatial analysis, and modeling. He holds a B.S. in Environmental Health Sciences from the University of Georgia, an M.S. in Entomology from Pennsylvania State University, and a Ph.D. in Entomology with minors in Statistics and Operations Research from Pennsylvania State University.

Research topics

• Biology
• Ecology
• Geography
• Zoology
• Botany

Selected publications

• Data from: Spatial and temporal patterns of bark beetle and defoliator outbreaks, and their interactions, in the Pacific Northwest

  Borealis · 2026-04-22

  datasetOpen accessSenior author

  <b>Abstract</b><br/><p>The dynamics of many forest insects are changing in response to climate warming; however, patterns are not always consistent among or within taxa. Changes in outbreak dynamics for individual species have received much recent attention, but the potential for interactions among species has received less. We used historical aerial survey data (1960-2019) from conifer-dominated forests of Oregon, Washington, and British Columbia to quantify spatial dynamics of bark beetles, defoliators, and their interactions across local and regional scales, and to measure how these dynamics have changed through time. The historical aerial survey data are archived by the British Columbia Ministry of Forests & Canadian Forest Service, and the USDA Forest Service, as cited in the paper; these data contain a record of aerially detected forest biotic disturbance agents (e.g., insects and plant pathogens) that date to the 1940s. From this large dataset, we subset those biotic disturbance agents specific to our study region (Oregon and Washington, USA, and British Columbia, Canada), which are listed in Table 1 in Pane et al. 2026, between 1960 and 2019. The subset data used in our study is archived here. The subset dataset contains 2034477 rows and 7 columns. Each row lists (1) a unique number associated with each grid cell, (2 and 3) the geospatial locations, (4) the year the biotic disturbance agent was detected or (5) the one year lag in detection (specific to bark beetle damage), (6) the biotic disturbance agent detected, and (7) and the area of the aerially detected disturbance. More details are contained in the README file.</p>

  PublisherDOI

• Data from: Spatial and temporal patterns of bark beetle and defoliator outbreaks, and their interactions, in the Pacific Northwest

  DRYAD · 2026-04-03

  datasetOpen accessSenior author

  The dynamics of many forest insects are changing in response to climate warming; however, patterns are not always consistent among or within taxa. Changes in outbreak dynamics for individual species have received much recent attention, but the potential for interactions among species has received less. We used historical aerial survey data (1960-2019) from conifer-dominated forests of Oregon, Washington, and British Columbia to quantify spatial dynamics of bark beetles, defoliators, and their interactions across local and regional scales, and to measure how these dynamics have changed through time. The historical aerial survey data are archived by the British Columbia Ministry of Forests & Canadian Forest Service, and the USDA Forest Service, as cited in the paper; these data contain a record of aerially detected forest biotic disturbance agents (e.g., insects and plant pathogens) that date to the 1940s. From this large dataset, we subset those biotic disturbance agents specific to our study region (Oregon and Washington, USA, and British Columbia, Canada), which are listed in Table 1 in Pane et al. 2026, between 1960 and 2019. The subset data used in our study is archived here. The subset dataset contains 2034477 rows and 7 columns. Each row lists (1) a unique number associated with each grid cell, (2 and 3) the geospatial locations, (4) the year the biotic disturbance agent was detected or (5) the one year lag in detection (specific to bark beetle damage), (6) the biotic disturbance agent detected, and (7) and the area of the aerially detected disturbance. More details are contained in the README file.

  PublisherDOI

• Native bee richness increases with wildfire burn severity in ponderosa pine forests

  Forest Ecology and Management · 2026-01-31

  articleSenior author
  PublisherDOI

• Spatial distribution, sampling efficiency and Taylor's power law: 3. Density‐dependent efficiency in emerald ash borer sampling schemes

  Agricultural and Forest Entomology · 2025-02-28 · 1 citations

  articleOpen accessSenior author

  Abstract Data of emerald ash borer caught in six trapping systems at 16 site‐years were compared to assess their relative sampling efficiency. One sample scheme was chosen against which the other five were compared, and their relative efficiencies estimated. Recommendations for the use of the emerald ash borer samplers were made based on the relative efficiency analysis results. Two sampling schemes were found to have density‐dependent efficiency relative to the other four schemes and are most sensitive at low population densities, therefore, making them most useful for detection. Of the other four schemes, two are sufficiently more efficient to be recommended for monitoring established populations. The results of a global Taylor power law (TPL) analysis of the sample data suggest a loss of information of density‐dependent sampling efficiency by TPL when its parameter is b = 2. This limits the use of TPL to evaluate the sampling efficiency of insect samplers.

  PublisherOA PDFDOI

• Citizen science data reveals winter warming delays cherry bloom in the Pacific Northwest, USA

  Plants People Planet · 2025-06-16

  articleOpen accessSenior author

  Societal Impact Statement Climate change is altering ecological systems, including the phenology of flowering plants. Shifts in the bloom date of cherry trees are a global concern considering their cultural, agricultural, and horticultural importance. Ornamental cherry is a prominent component of the University of Washington campus (Seattle, USA), providing an opportunity to engage volunteers in citizen science that quantifies shifts in bloom in the Pacific Northwest. These phenological shifts affect horticultural systems, cherry festival planning, and synchrony with pollinators, with direct implications on local economies, tourism, and landscape resilience for future generations. Summary We monitored cherry bloom date on the University of Washington campus, Seattle, USA, in three flowering cherry species and cultivars to develop a predictive model for estimating bloom, and to quantify changes in bloom date in Somei‐yoshino cherry ( Prunus x yedoensis ) between 1966 and 2024. We worked with citizen scientists to record bloom date, and for Prunus x yedoensis , bloom phases, using ArcGIS Field Maps between 2012 and 2024. We also examined newspaper archives to reconstruct the observed bloom date for Prunus x yedoensis prior to 2012. We used a published modeling framework to develop species‐ and cultivar‐specific models to predict bloom. We observed different thresholds for chill and heat requirements across flowering cherry species and cultivars, and general congruence between observed and model‐predicted bloom dates for each. Using the longer time series in Prunus x yedoensis , we observed that warmer winters slowed the accumulation of required chill units, while warmer springs led to required heat units accruing more rapidly. The net effect of warming winters and springs resulted in a delay in the bloom date of Prunus x yedoensis by ~2 days per decade between 1966 and 2024. Shifts in the bloom date of flowering plants could result in phenological asynchrony with pollinators, with cascading effects across ecosystems. Further research is needed to understand the complex responses of flowering plants to shifting climatic conditions.

  PublisherOA PDFDOI

• What Is a Specialist? Quantifying Host Breadth Enables Impact Prediction for Invasive Herbivores

  Ecology Letters · 2025-02-01 · 3 citations

  letter

  Herbivores are commonly classified as host specialists or generalists for various purposes, yet the definitions of these terms, and their intermediates, are often imprecise and ambiguous. We quantified host breadth for 240 non-native, tree-feeding insects in North America using phylogenetic diversity. We demonstrated that a partitioning of host breadth: (1) causes 67% of non-native insects to shift from a generalist to specialist category, (2) displays a reduction in host breadth from the native to introduced range, (3) identifies an inflection point in a model predicting the likelihood of non-native insect ecological impact, with a corresponding change in behaviour associated with specialists versus generalists, and (4) enables three models for strong prediction of whether a non-native forest insect will cause high impacts. Together, these results highlight the primacy of how herbivore host recognition and plant defences mediate whether novel host interactions will result in high impact after invasion.

  PublisherDOI

• Patterns and drivers of biotic disturbance hotspots in western United States coniferous forests

  Ecography · 2025-07-03

  articleOpen access

  Globally, forest disturbances caused by herbivorous insects and plant pathogens (i.e. biotic disturbances) have increased since the 1990s, a trend linked in part to climate warming. With increases in biotic disturbance activity, an emerging ecological phenomenon has been documented: biotic disturbance ‘hotspots', or areas where two or more biotic disturbance agents co‐occur in space and time. Biotic disturbance hotspots may have important implications for forest resilience, particularly if they erode mechanisms of post‐disturbance forest recovery. The factors leading to hotspot occurrence, however, remain poorly understood. We characterized the patterns and drivers of biotic disturbance hotspots occurring from 2000 to 2020 across three broad forested regions in the western United States (US; the Southern Rockies, Middle Rockies, and Cascades). Using Bayesian spatio‐temporal models, we evaluated whether hotspots can be predicted from predisposing factors expected to increase forest susceptibility to biotic disturbance (i.e. forest composition, topography, and average climate), as well as inciting factors known to trigger individual bark beetle and pathogen outbreaks (i.e. annual weather). Biotic disturbance hotspots exhibited distinct spatio‐temporal patterns and trends within each region. Forest structure and composition were the strongest and most consistent drivers of hotspots. Other factors varied in their importance by region, reflecting regional differences in biophysical context. Relative to the predictor variables included in our models, estimated spatio‐temporal random effects were more closely correlated with model predictions, suggesting that dynamic factors such as outbreak spread strongly shape patterns of biotic disturbance hotspots. Our results illustrate the widespread nature of biotic disturbance hotspots across western US coniferous forests and demonstrate the importance of forest structure and regional outbreak dynamics in anticipating hotspots at regional scales. These findings provide a deeper understanding of interacting forest disturbances and have important implications for the resilience of forests during a period marked by continued increases in disturbance activity.

  PublisherOA PDFDOI

• Author response for "Patterns and drivers of biotic disturbance hotspots in western United States coniferous forests"

  2025-05-12

  peer-review
  PublisherDOI

• First records of eight native bee species (Hymenoptera, Anthophila) in Washington, USA

  Check List · 2025-04-01 · 1 citations

  articleOpen accessSenior author

  Pollinators are an essential component of ecosystem function, and declining bee populations are a global conservation concern. Despite this importance, there is a lack of understanding regarding the distribution of native bee species across western North American landscapes. This study documents new records of Melissodes nigracauda LaBerge, Dufourea dilatipes Bohart, Atoposmia abjecta abjecta Cresson, Coelioxys funerarius Smith, Dianthidium cressonii Dalla Torre, Dianthidium singulare Cresson, Osmia cyaneonitens Cockerell, and Stelis heronae Sheffield. These eight new records supplement the ~565 bee species previously documented in Washington state.

  PublisherOA PDFDOI

• Author response for "What Is a Specialist? Quantifying Host Breadth Enables Impact Prediction for Invasive Herbivores"

  2024-11-09

  peer-review
  PublisherDOI

Recent grants

• Collaborative research: A landscape resistance mapping approach to understanding species invasion patterns

  NSF · $180k · 2016–2020

Frequent coauthors

• Andrew M. Liebhold

  Czech University of Life Sciences Prague

  42 shared

• Kenneth F. Raffa

  University of Wisconsin–Madison

  19 shared

• Laura Blackburn

  Northern Research Station

  15 shared

• Michael C. Saunders

  Pennsylvania State University

  15 shared

• Donna S. Leonard

  US Forest Service

  13 shared

• Peter B. Reich

  University of Minnesota

  13 shared

• Barbara Bentz

  Rocky Mountain Research (United States)

  12 shared

• Daniel A. Herms

  Vall d'Hebron Hospital Universitari

  12 shared

Education

• PhD, Entomology

  Pennsylvania State University

  2002

• MS, Entomology

  Pennsylvania State University

  1997

• BS

  University of Georgia

  1991