Principal Investigator - Janneke Hille Ris Lambers
Janneke HilleRisLambers
I received my Ph.D. from Duke University in 2001 (working with James S. Clark). While at Duke, my field work took me to the Coweeta Hydrologic Laboratory in western North Carolina (an LTER site), where I studied differences among temperate tree species in seed dispersal, seed banking and density-dependent mortality, and how those differences contribute to diversity-maintenance.  I then worked with David Tilman at the Cedar Creek Ecosystem Science Reserve (another LTER site associated with University of Minnesota). There, I studied how declining diversity and species identity influences productivity and the impacts of global change on seed production. In a subsequent postdoc at University of California, Santa Barbara (working with Jonathan Levine), I focused on the factors that allowed Mediterranean annual grasses to dominate over the diverse California annual grasses and forbs as well as the contributions of niche and neutral processes to the coexistence of Serpentine annuals.  I arrived at University of Washington in 2006.

I am a plant community ecologist broadly interested in: 1) the maintenance of species diversity and 2) how global change (climate change, invasive species, nitrogen deposition, etc) alters the structure and function of plant communities.  I approach questions of interest with observational studies, manipulative experiments, and statistical modeling, and have worked in a variety of habitats (temperate forests, tall grass prairies, annual grasslands), although these days my field research primarily occurs in the temperate coniferous rainforests of Washington State. Check out the Research page on this website for more information on current projects, and the Publications page for information on current and past work.

Graduate Student - Leander D.L. Anderegg

Leander DL AndereggI am broadly interested in the ecological impacts of climate change, with a current focus on tree species range shifts. Given the rapidity of current and projected environmental changes, we have neither the time nor the resources to study every species that may require conservation action over the coming century. I seek to understand biogeographic patterns by understanding the nature of range constraints so that we can predict which tree species are likely to experience range shifts and where range shifts will occur, even in the absence of detailed demographic data. For example, where are tree ranges more likely to be biotically constrained vs. abiotically constrained? How do ecotypic variation and phenotypic plasticity influence range boundaries? How do range constraints scale from elevational ranges to latitudinal ranges? I address these questions by combining physiological, ecological, and biogeographic data.

As a native of Colorado, I grew up camping, hunting and fishing in the mountains of the Southwest where I witnessed first hand the ecological impacts of anthropogenic climate change. I began my research career as an undergraduate at Stanford University, studying the causes and consequences of recent drought-induced trembling aspen tree mortality in the Colorado Rockies. The results of this research (aspen forests are becoming increasingly physiologically vulnerable to drought and high temperatures, making future die-offs likely) launched me into a broader exploration of how climate change will affect the major forests of the western US. I joined the lab in 2012.


Graduate Student - Ian Breckheimer

Ian BreckheimerHow do gene flow and local adaptation interact to define niche boundaries and geographic ranges? Answering this question is critical if we want to successfully manage ecosystems under climate change.  The climate optima of many species are expected to shift north by 700km and up in elevation by 800m over the next century due to climate change, putting tremendous pressure on plants to adapt or migrate. Despite these challenges, some recent models predict that long-distance dispersal of pollen may allow some species to rapidly adapt in place to shifting climates.  These predictions depend strongly on assumptions about phenology, gene-flow and local adaptation that are poorly constrained by data.  I intend to use molecular tools, common-garden experiments, and experimental crosses to determine how gene flow and hybridization influences current and future distributions of Mimulus guttatus and Mimulus tilingii (monkey flower species with contrasting altitudinal distributions).  

Originally from North Carolina, I’m joining the lab in 2012 after completing a masters degree with the Landscape Ecology and Biogeography group at UNC Chapel Hill.


Graduate Student - Stuart Graham

Stuart GrahamIn response to climate warming, many species are expected to expand their ranges towards the poles or higher altitudes. Although such range shifts are widely documented, the range limits of some species have not changed. This interspecies variation arises because range limits are often constrained by factors other than environmental conditions, such as weak dispersal ability and/or interactions with others species. Species interactions are likely to be particularly important for the range shifts of plant species, the growth and survival of which are strongly influenced by both mutualistic fungi and soil-borne pathogens. Specifically, the absence of appropriate mycorrhizal fungi beyond range limits may prevent range shifts but the absence of soil-borne pathogens may enhance range shifts. To understand how plant ranges will shift in a changing climate, we need to investigate how these positive and negative effects of soil biota combine to influence plant growth and survival. I am looking forward to combining growth chamber experiments and manipulative field experiments to investigate how plant-soil feedbacks may influence tree range expansion to higher altitudes in the Cascade Range of Washington.

As a native of rural Northern England, I completed my undergraduate degree at the University of Bristol in the UK. I received master’s degrees from Uppsala University (Sweden) and University of Montpellier II (France) through my participation in the Erasmus Mundus Master Programme in Evolutionary Biology (MEME). After completing the final semester of my master’s program at Harvard University, I moved to the west coast where I worked as a research assistant at UC Santa Barbara. I joined the lab as a graduate student in 2017.

Graduate Student - Meera Sethi

Meera SethiIf no man is an island, neither is any plant, insect, bird, bacterium, or other form of life on earth. From birth to death, all organisms are caught up in a complex network of interactions—both positive and negative—with other living things. For some, these relationships are important enough to play a role in determining vital outcomes like survival, reproductive success, and distribution range limits. What will happen to individual species and to communities if a warming planet induces significant shifts in biotic interactions? I am coming to the Hille Ris Lambers lab with a broad interest in this question. I am particularly curious about the impacts of climate change on multitrophic interactions involving three (or more!) parties and spanning different abiotic niches, such as the aboveground-belowground relationships we see among plants, soil microbes, and insect herbivores/pollinators. In multitrophic interactions, indirect effects can occur where the effect of one species on another is mediated by a third. I am looking forward to working on designing ways of observing, quantifying, and experimentally manipulating such indirect effects. 

I was born and raised in Singapore, and made my way to Seattle by way of Boston, Chicago, and Berkeley. In that time I earned a B.A. in Comparative Literature and an M.A. in Children’s Literature and Teaching, and worked as a middle school humanities teacher and a textbook editor before finally giving in to my late-blooming love of science. Since 2007 I have been a freelance science writer and since 2011, a serial field technician on ecological research projects in Sweden, Alaska, and California. I am joining the lab in 2015 and am thrilled to be part of this smart, happy, productive group of researchers.

My blog is here.

Postgraduate Researcher - Alec Baird

Alec BairdI joined the lab in 2013 and assisted Dr. Steve Kroiss with his work on sapling growth rates across climatic gradients on Mt. Rainier. Currently, I am co-advised by Dr. Janneke Hille Ris Lambers and Dr. Liz Van Volkenburgh, and co-mentored by Leander Love-Anderegg (PhD Candidate) and Melissa Lacey (
PhD Candidate). I am broadly interested in modifications in plant form and function in response to key climatic as well as biotic constraints (such as competition).

My own project aims to identify variation in Populus tremuloides (trembling aspen) leaf morphology and physiology across the species' elevational range. More specifically I want to address how specific leaf morphology and physiology interact to mediate function, survival, and growth in P. tremuloides in the face of increasing drought. Further, how might adaptive traits and the variation in adaptive traits function in influencing current and future range distributions?

I graduated spring of 2016 and plan continue on to graduate school to pursue my Phd in plant biology, with central themes being tree ecophysiology and the ecological impacts of climate change.


Undergraduate Researcher - Myesa Legendre-Fixx
Alec BairdI am an oceanography major currently working towards declaring a degree in ecology, evolution and conservation biology. I am incredibly interested in both fields, particularly how oceanic systems and land-based communities are responding and will continue to respond to climate change. I am intrigued by the big picture of nature and how the components, both abiotic and biotic, exist as a tumultuous, violent, and beautiful system. The studies of oceanography and ecology are both ways of studying our world through a broad scope. Oceanographers take an interdisciplinary approach, investigating how abiotic factors such as currents and nutrients affect marine life and ocean processes. In the same way, ecologists are interested in how communities interact, function and change, rather than the mechanics of how an individual exists. Climate change is already affecting both marine and terrestrial ecosystems. It is important to learn what these changes will be in order to better take care of our resources and planet. 

During my time here at the University of Washington, I’ve done a variety of research and internships in completely different environments. I’ve worked in a biological oceanography lab, on the research vessel R/V Thompson on the open ocean, at NOAA interviewing experienced Bering Sea crab fishermen, and on Mt. Rainier doing ecology fieldwork for the Hille Ris Lambers lab, as well as working in the lab during the school year (see CV for more detail). Currently, I’m investigating if the climate variables that control the growth of high-elevation tree species are different in different climate regimes (i.e. on different sides of Mt. Rainier). To do this, I have been learning how to plot data in R and I will apply cross-dating techniques to a number of tree cores.

After completing a bachelor’s degree in both oceanography and ecology, I aim to attain a Ph. D.  in either one of those fields. My ideal job would involve working in a team of interdisciplinary scientists, striving to anticipate an ecosystem’s responses to global change and working to restore habitat already damaged by anthropogenic changes.  I would like to be a scientist behind restoration efforts, devising plans on how to repair at risk or damaged areas in order to preserve natural resources, ecosystem services, diversity and beauty for posterity. In addition to scientific work, I will teach others how organisms, processes, and climate are deeply interconnected and hope to convince community members of the paramount importance of gaining a better understanding of our planetary systems---so that we can make better predictions, and therefore better maintain our planet.

My CV is here.

Undergraduate Researcher - Tristan O'Mara

Tristan O'MaraAfter volunteering as a field assistant in the summer, I joined the lab in the fall of 2015 as a research assistant. I am currently a senior double majoring in Biology and Environmental Science and Resource Management. There are many areas of science that grab my attention, but my current focus is on alpine ecology and remote sensing.

Throughout my time at the University of Washington, I have involved myself in a variety of different types of ecological research. My research while studying in the Peruvian Amazon focused on riparian successional plant densities in relation to light availability in varying habitats. Currently, I am involved in a research project tracking the mortality of Sword Ferns in Seward Park, Seattle WA. Over the past year, I have been monitoring a die off of sword ferns that has been spreading throughout this park. In a month, I will depart for Thailand and Indonesia for a few weeks to study and research marine ecosystems and coral reef biodiversity. My independent project with the lab looks to quantify how tree line has changed over the past century on Mount Rainier using repeat oblique and aerial photography. For this project, I have been using GIS and QGIS to implement polygons into the historical and repeat photographs. This project is important because it will help show the extent to which tree line is encroaching in the subalpine meadows from a spatial perspective.

In addition to ecology, environmental education and outreach is something I’m highly interested in. In my previous positions with the Seattle Aquarium and Outdoor Nation, I learned I enjoy teaching and advocating for the outdoors. My time studying abroad in Peru also helped fuel my passion for environmental outreach. I returned to Peru this past summer as a Teaching Assistant to help share my knowledge and teach various research techniques. These experiences helped change my perspective and lifestyle to live as sustainable and waste free as possible.

After I graduate, I plan to continue to further my research experience, learning more about climate modeling, and the newest remote sensing applications. Sooner rather than later, I hope to pursue a Masters or PhD in some combination of Ecology, Remote Sensing Science, and Education.

Undergraduate Researcher - Elise Pletcher
Elise PletcherI first became interested in ecological research as a volunteer for the Earth Watch Institute in Ecuador, and have since been fascinated with interaction between plants and their environment, including influences by climate, deforestation, and habitat destruction. As a student for the SIT institute study abroad program, I studied the state of secondary forest succession along an international park boundary in Panamanian cloud forest.

In 2015 I joined the lab assisting in data processing and analyzing seed production data across six focal conifer species – specifically Dr. Hille Ris Lambers and I looked at patterns of masting (years of large seed production followed by years of extremely low seed production). Understanding the mechanisms behind mast seeding is important, as masting can control tree population demography and influences ecosystem dynamics. This pattern is both evolutionarily favorable and influenced by climatic factors (rainfall, growing season temp.). I am interested in determining how recent years of unusually high growing season temperatures will affect the masting pattern we see, and what implications climate change has on this process.

After I complete my B.S. in biology in the spring I aim to continue doing ecological research, and prepare for graduate school. Ultimately, I look forward to a career in mitigating and better understanding the impacts of climate change.

Undergraduate Researcher - Teodora Rautu
Teodora Rautu

I’m an environmental science and resource management major with a minor in quantitative science. My interest in ecology began with my appreciation of the rich Pacific Northwest forests that I was lucky enough to grow up around. As I got the chance to travel to starkly different environments, such as the Grand Canyon and Costa Rica, I became more aware of the vast range of habitats and curious of the intricate interactions that occur in each differing system. My fascination of these intricacies grew as I participated in various restoration projects that made me realize just how important it is to preserve this complexity. Because rapid global warming is becoming a bigger threat to biodiversity, I am very interested in how climate change will affect the dynamics of ecosystems and impact the success of species’ populations.

Currently, I am studying the population dynamics of the mountain monkeyflower Mimulus tilingii. Specifically, I am looking at how the environment, gene flow, local adaptation, and their combined effects influence this plant’s response to increasing temperature. By building population models in R, I’m seeing which factors contribute the most to population growth and determine species’ survival. Why population limits fluctuate will then help us understand how species might alter interactions within its ecosystem and get a better indication of what to expect in the future. In addition, studying population dynamics can tell us which management decisions are best to ensure species’ survival.

In the future, I plan on continuing climate change related research to learn more about the ecological dynamics of species’ interactions. Human induced global warming unfortunately threatens a lot of the biological world, and I want to contribute to conservation efforts by conducting research that will make better informed decisions regarding management practices.

Research Assistants
  Jessie Hild (undergraduate research assistant 2016-present)
  Kyra Kaiser
(undergraduate research assistant 2016-present)
  Aden Kinne (undergraduate research assistant 2016-present)
  Cole Lysgaard (undergraduate research assistant 2016-present)


Cynthia Chang (postdoc: 2012-2014). While in the HilleRisLambers lab, Cynthia applied trait-based and phylogenetic based approaches to a plant community assembly data set from Mt. St. Helens. Cynthia is currently an assistant professor at University of Washington, the Bothell campus (Bothell, WA).

Ailene Ettinger (grad: 2007-2013). While in the HilleRisLambers lab, Ailene studied the relative importance of climatic constraints and competitive interactions for the performance of six conifer trees at their altitudinal range limits within Mt. Rainier National Park, using dendroecological techniques and a manipulative transplant experiment to answer her questions. Ailene is currently an NSF Math-Bio Fellow at Tufts University University (Medford, MA). 

Elli Theobald (grad: 2010-2016). Elli focused on the relative importance of plant-pollinator interactions for range limits and the role of climate in driving wildlflower phenology while in the lab. Additionally, Elli spent time thinking about how to best teach climate change impacts to undergraduates, and was instrumental in helping establish MeadoWatch, our lab citizen science program. Elli is currently a postdoctoral research fellow working with BERG (the Biology Education Research Group) in the Biology Department at University of Washington.

Kevin Ford (grad: 2008-2014). While in the HilleRisLambers lab, Kevin worked on a number of projects, including the relevant scale of microclimate variability for subalpine vegetation distributions; the relationship between tree growth across range limits, and the relative importance of climate and edaphic conditions for range expansions of treeline and subalpine plants. Kevin is currently a post doctoral research associate at the US Forest Service Pacific Northwest Research Station (Olympia, WA).

Melanie Harsch
(postdoc: 2012-2015). While in the HilleRisLambers lab, Melanie worked on range shifts of western plant species, using large databases. Melanie is currently a data analyst for NOAA.

Steve Kroiss (postdoc: 2012-2015). While in the HilleRisLambers lab, Steve worked on recruitment limitation of conifers as well as creating IPM models for Pacific silver fir. Steve is currently a data analyst for Intellectual Ventures.

Haldre Rogers (grad: 2006-2011). Haldre Rogers was co-located in the Tewksbury and HilleRisLambers labs while at the University of Washington. Haldre studied the impacts of complete bird loss on Guam on the dispersal of tree seeds (with the majority of species in Guams forests dispersed by birds) and the insect herbivory of tree seedlings (potentially controlled by bird predation). Haldre continues to work in this amazing system (see her project website), and is currently an assistant professor at Iowa State University.
Susan Waters (grad: 2007-2013). While in the HilleRisLambers lab, Susan studied the role of indirect, pollinator-mediated interactions between native and exotic plants in a rare and heavily invaded habitat - south Puget Sound Prairies. Susan is also the co-founder of the awesome Urban Pollination Project (a citizen science project documenting urban pollination services in Seattle). Susan is currently a rare species ecologist working with the Center of Land Management (CNLM) in Olympia, Washington.

Anna Wilson (lab manager, MeadoWatch Volunteer coordinator: 2012-2015). While in the lab, Anna coordinated our MeadoWatch program, kept the lab running, and participated in many aspects of research (including a study on frost tolerance of conifer seedlings). Anna is currently a lab technician at Cornell University.

Sylvia Yang (grad: 2006-2011). Sylvia was co-located in the Ruesink and HilleRisLambers labs while at the University of Washington. Sylvia worked on the ecosystem engineering abilities of eelgrass (Zostera marina), using observations, experimental manipulations, and modeling. Sylvia is currently a Marine Scientist at the Shannon Point Marine Center (Anacortes, WA), which is affiliated with Western Washington University (Bellingham, WA).

Undergraduate and Postgrad Alumni
  Leila Ayad (Doris Duke Conservation Scholar Intern 2016)
  Aden Kinne (Field Ecology Intern 2016)
  James Martin (Doris Duke Conservation Scholar Intern 2016)
  Soline Martine-Blangy (Visiting Student 2016)
  Tatsu Ota
(Field Ecology Intern 2016)
  Alex Wall (Field Ecology Intern 2016)
  Rachel Brunner (2015 Cascade Legacy Field Crew Leader)
  Kaitlyn Engel
(Mt. Rainier Research Intern 2015)
  Colin Fagan (Mt. Rainier Research Intern 2015)
  David Grow (Mt. Rainier Research Intern 2015)
  Adrienne Hampton (Mt. Rainier Research Intern 2015)
  Emmi Lia (2016 Field Crew Leader, Mt. Rainier Research Intern 2015)
  Laurel Sebastian (REU 2015)
  Hannah Besso (Mt. Rainier Research Intern 2014)
  Emily Chan (Mt. Rainier Research Intern 2014)
  Drew Lyons (Mt. Rainier Research Intern 2014)
  Lane Felker (Mt. Rainier Research Intern 2013, undergraduate researcher 2013-2014)
  James Lucas (2014 Mt. Rainier REU)
  Gregor Siegmund
(2014 Field Crew Leader, Mt. Rainier Research Intern 2013)
  Hannah Wiesner (2015 Field Crew Leader, Mt. Rainier Research Intern 2014)
  Cherry Chen (Mt. Rainier Research Intern 2013, undergraduate researcher 2011-2013)
  June Landenburger (Mt. Rainier Research Intern, undergraduate researcher 2013-2014)
  Jacqui Levy (Mt. Rainier Research Intern 2013)
  Katy Olsen (
Mt. Rainier Research Intern 2013)
  Sam Reed (Mt. Rainier Research Intern 2013, postgrad researcher 2013-2014)
  Caitlin Budd (
Mt. Rainier Research Intern 2012)
  Kathleen Burns (summer REU: 2012)
  Liam Fitzgerald (
Mt. Rainier Research Intern 2012)
  Natasha Lozanoff (Mt. Rainier Research Intern 2012)
  Anna O'Brien (undergraduate researcher, lab manager: 2007-2011): currently a graduate student at UC Davis
  Sara Eshe (undergraduate researcher: 2010-2011)
  Melissa Winstanley (undergraduate researcher: 2009 - 2010)

  Irene Weber (undergraduate researcher: 2009 - 2010): currently a graduate student at Southern Illinois University
  Courtenay Ray (Mt. Rainier Research Intern 2011): currently a graduate student at UC Santa Cruz
  Jennifer Rickwalt (
Mt. Rainier Research Intern 2011)
  Mitch Piper (
Mt. Rainier Research Intern 2010, Crew Leader 2011-2012)
  Courtney Wenneborg (
Mt. Rainier Research Intern 2010)
 Jonathan Deschamps (undergraduate researcher, Mt. Rainier Research Intern 2007 - 2009)
  Gerald Lisi (
Mt. Rainier Research Intern 2008, 2009)
Alan Wright (Mt. Rainier Research Intern 2009)
  Rachel Konrady (
Mt. Rainier Research Intern 2009)
  Tony Krueger (
Mt. Rainier Research Intern 2009)
  Amado Fuentes (
Mt. Rainier Research Intern 2008) 

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Biology Department
University of Washington
Seattle WA, 98195-1800
jhrl@uw.edu, 206-543-7389