Trevor Branch

  • Associate Professor, SAFS
  • Faculty Member, UW QERM Graduate Program

Research areas

Our lab focuses on solving biological problems through data synthesis and mathematical models and work on a variety of research projects, including:

My graduate students and postdocs are currently working on modeling oceanographic factors and herring status in Prince William Sound, modeling how to improve management of California market squid, predicting which species are most likely to be threatened by extinction because of opportunistic exploitation, and (soon) estimating and modeling sex ratios in whale populations.

Joining the lab

Our group is committed to provide a diverse and welcoming environment. We condemn any sort of discrimination based on race, gender, sexual orientation, cultural identity, physical appearance, or religion. Science can only be advanced when different perspectives are considered and included. 

Expectations for prospective students: The work we do focuses on computer modeling, synthesis, and meta-analysis, and melds ecological theory with mathematics, statistics, and computer programming. Prospective students should therefore have skills in mathematics, statistics, and programming, together with a strong interest in ecology, fisheries, or whales. Science communication is also key, and we focus on how to present your science in writing and verbally, and encourage science communication, e.g. @TrevorABranch on Twitter.

Funding: All graduate students at SAFS (and QERM) are fully funded, usually on fellowships, teaching assistantships, or most commonly research assistantships (RAs). RAs pay a monthly stipend, provide a tuition waiver, and include health insurance, and are paid from a grant. Obtaining funding for your graduate studies is therefore very important, but research grants are highly competitive. Students who are able to secure a fellowship will have much more freedom to focus on their own projects without grant funding requirements. SAFS does offer a few fellowship awards each year to select students, which do not need to be applied for; in addition, incoming students should consider the NSF Graduate Research Fellowships, NOAA Nancy Foster Fellowships, NOAA Margarent A Davidson Graduate Fellowship, the NMFS Sea Grant Joint Fellowship Program, and the Ford Foundation. The QERM program, which involves a rigorous math/stats/applied math set of courses in the first three quarters, also funds students for those three quarters.

Moving forward: If all of this sounds interesting and good to you, please send me an email. My students have written up this helpful email template for prospective graduate students.

The email should include (1) your CV, (2) unofficial transcripts, (3) a couple of paragraphs about your research interests, skills, abilities, and career goals, (4) a short statement about your math, statistics, programming, and biology background, and (5) a recent written example of your work. Tell me a bit about your background, why you are interested in working with us, and what kinds of research interest you. I may have a virtual meeting with you, but don’t have a time to meet with every prospective student. Note that out of fairness to all applications, I do not make any final decisions about extending offers to incoming students until Jan of the year of admission, once I know the status of my research grants and have viewed all relevant applications.

To apply: assuming we have had a stimulating conversation over email, send your application in to SAFS (and/or QERM) by the deadline, mentioning my name as an advisor you are interested in working with. Prospective students will normally (covid-willing) be invited to the prospective student day in late February to meet with advisors in person and explore SAFS, the University of Washington, and the Seattle surroundings.

Current lab members

John Trochta (PhD)

John conducts the annual Bayesian assessment of Prince William Sound herring, has completed a global meta-analysis of herring trends and causes for their frequent collapse, and is currently working on including herring disease as a component of natural mortality into fisheries stock assessments.  

Caitlin Allen Akselrud (PhD)

Caitlin is working on a multi-species management strategy evaluation for California forage fish fisheries. Part of this involves developing a machine learning model for predicting California market squid (Doryteuthis opalescens) abundance, to better manage this species, which is the most valuable fishery in California. Caitlin is a Research Fish Biologist at the Alaska Fisheries Science Center.

Stephanie Thurner (MS)

Stephanie uses computer simulations to understand if — and when — the human harvest of economically valuable species can lead to extinction. She is also building a public database that contains trends in the relative abundance of various species from fisheries-independent surveys. Ultimately, she plans to work in resource management at the interface of biology and mathematics to help resource managers make informed decisions that ensure sustainable fisheries and healthy ecosystems.

Beatriz Dos Santos Dias (postdoc)

Beatriz is part of the project modeling and stock assessment of Prince William Sound herring (in the Gulf of Alaska), she is investigating the drivers of herring spawn timing from population time series, and oceanographic and climatological variables. This work will improve our knowledge of Prince William Sound herring and the stock assessment model. In the past, she developed population, ecosystem, and spatial fuzzy logic models for a variety of species including sea turtles, sharks, and river herring.

Past lab members

Peter Kuriyama (PhD, SAFS): simulated biases involved in hook-and-line surveys, and examined the effects of catch share fisheries on fishing behavior on the US west coast. Currently a research mathematical statistician at NOAA, Southwest Fisheries Science Center.

Merrill Rudd (PhD, SAFS): developed new modeling tools to assess the status and trends in data-limited fisheries, and whether unreported catches lead to overfishing. Currently leads scientific consulting company Scaleability LLC, which conducts fisheries assessments around the world.

Cole Monnahan (MS, PhD, QERM): assessed the status of eastern North Pacific blue whales, and implemented new Bayesian algorithms that speed up fisheries stock assessments by a factor of 50 to 50,000. Currently a research mathematical statistician at NOAA, Alaska Fisheries Science Center. 

Melissa Muradian (MS, QERM): created a Bayesian stock assessment for Prince William Sound herring, and assessed the value of different types of information collected to manage that fishery. Currently leads Ecosa Consulting LLC, and environmental consulting company specializing in water quality and trout management, with Henry’s Fork Foundation as a major client.

David McGowan (postdoc): identified major shifts in both space and time of herring spawning in Prince William Sound from surveys covering nearly 50 years. Currently a Research Fish Biologist at NOAA, Alaska Fisheries Science Center.

Lewis Barnett (postdoc): identified areas with corals and other sensitive habitat, at risk from trawling; and showed that old fish have been greatly reduced by fishing. Currently a Research Fish Biologist at NOAA, Alaska Fisheries Science Center. 

Sean Anderson (postdoc): researched the portfolio effect in fisheries, assessed data-poor fisheries, and estimated the frequency of black swan events in animal populations. Currently a research biologist at Fisheries and Oceans Canada, Pacific Biological Station, Nanaimo. 

Matthew Baker (postdoc): defined ecological regions in the Eastern Bering Sea; currently the Science Director at the North Pacific Research Board.


Areas of Expertise

  • Fisheries stock assessment
  • Ecological modeling and statistics
  • Marine conservation
  • Marine food webs
  • Catch share fisheries
  • Large cetaceans

Community Engagement and Awards

Selected service

  • Scientific Review Group, USA-Canada Pacific Whiting/Hake International Treaty Organization since 2015
  • Invited participant to the Scientific Committee of the International Whaling Commission starting in 2000
  • Member of four NCEAS working groups
  • Peer reviewer for 68 journals including Science and Nature
  • Active science communication outreach through @TrevorABranch and @BlueWhaleNews on Twitter, with a combined 17,500 followers and 9.1 million views per year

Selected awards

  • 2013 College of the Environment Outstanding Researcher Award
  • 2013 Leopold Leadership Fellow
  • 2011 Sustainability Science Award, Ecological Society of America

Selected publications

  • 2013. T. A. Branch, A. S. Lobo, and S. W. Purcell. Opportunistic exploitation: an overlooked pathway to extinction. Trends in Ecology and Evolution 28:409-413.

  • 2020. Trochta, J. T., T. A. Branch, A. O. Shelton, and D. E. Hay. The highs and lows of herring: A meta-analysis of patterns in herring collapse and recovery. Fish and Fisheries 21:639-662.

  • 2010. Branch, T. A., R. Watson, E. A. Fulton, S. Jennings, C. R. McGilliard, G. T. Pablico, D. Ricard, and S. R. Tracey. The trophic fingerprint of marine fisheries. Nature 468:431-435.

  • 2009. Worm, B., R. Hilborn, J. K. Baum, T. A. Branch, J. S. Collie, C. Costello, M. J. Fogarty, E. A. Fulton, J. A. Hutchings, S. Jennings, O. P. Jensen, H. K. Lotze, P. M. Mace, T. R. McClanahan, C. Minto, S. R. Palumbi, A. M. Parma, D. Ricard, A. A. Rosenberg, R. Watson, and D. Zeller. Rebuilding global fisheries. Science 325:578-585.

  • 2007. Branch, T. A. and 42 coauthors. Past and present distribution, densities and movements of blue whales Balaenoptera musculus in the Southern Hemisphere and northern Indian Ocean. Mammal Review 37:116-175.

  • 2019. Monnahan, C. C., T. A. Branch, J. T. Thorson, I. J. Stewart, and C. S. Szuwalski. Overcoming long Bayesian run times in integrated fisheries stock assessments. ICES Journal of Marine Science 76:1477-1488.

  • 2017. Barnett, L. A. K., T. A. Branch, R. A. Ranasinghe, and T. E. Essington. Old-growth fishes become scarce under fishing. Current Biology 27:2843-2848.

  • 2017 Anderson, S. C., T. A. Branch, A. B. Cooper, and N. K. Dulvy. Black-swan events in animal populations. Proceedings of the National Academy of Sciences U.S.A. 114:3252-3257.