warning: Creating default object from empty value in /mount/ebs/www/html/modules/taxonomy/ on line 33.

Terence Leach

I am currently a freshman attending the University of Washington- Seattle, intending to major in Ecology, Evolution, and Conservation Biology with a minor in Marine Biology. I started working in the Rocap Lab with graduate student Michael Carlson over the summer while taking part in a program called GenOM ALVA, and have been conducting undergraduate research for the last two quarters. My current project is sequencing genes from Pseudo-nitzschia species and trying to reconstruct their evolutionary relationships. My long term interests include going to graduate school to further my studies in marine biology and to eventually become a marine biologist.

Nicolette Donohue

I am currently a Junior double majoring in Oceanography and Biology at the University of Washington. I began working with Michael in the fall of 2011. I'm interested in isolating and characterizing new viruses that infect the diatom Pseudo-nitzschia, and seeing how these viruses affect Pseudo-nitzschia communities in the field.

Jennefer Lopez



I am currently a freshman at the University of Washington.


The summer of 2010 I began in the Rocap Lab in association with the University of Washington's Alliances for Learning and Vision for Underrepresented Americans (ALVA) prorgram. I did a research project about the pH effects on Prochlorococcus. Now I am currently working with the preservation of Synechococcus cultures.

Jaci Saunders


Jaci at Discovery Park in Seattle


 B.S. Biological Sciences, B.A. Political Science. University of Pittsburgh. Pittsburgh, PA (2007).

M.S. and Ph.D. Oceanography. University of Washington. Seattle, WA (2009-present).


 Work Experience:

 ·        National Science Foundation – Research Experience for Undergraduates, Kalisz Lab, Evolutionary & Population Plant Genetics. University of Pittsburgh. Pittsburgh, PA (2007).

 ·        The Student Conservation Association-National Parks Internship Program:

o   Environmental Policy Intern – Former U.S. Representative Christopher Shays (CT-04) Washington, D.C. (1/2008-4/2008).

o   Department of Interior, External Affairs Office Intern. Washington, D.C. (5/2008).

o   Padre Island National Seashore, Science & Natural Resources Management Americorps Intern. Corpus Christi, TX (6/2008-9/2008).

 ·        Smithsonian Environmental Research Center Internship. Edgewater, MD.

o   Plant Ecology Lab – Developed enzyme assays to study effects of invasive earthworms on soil microbial communities in temperate forests (9-12/2008).

o   Protistan Ecology Lab – Studied infections of the toxigenic dinoflagellate Alexandrium tamarense by the parasitic dinoflagellate Amoebophrya sp. (1-4/2009).

 ·        Natural Resources Seasonal Ranger, National Mall & Memorial Parks, National Park Service. Washington, D.C. (6-8/2009).


 Research Interests:

            I am interested in how the marine cyanobacterium Prochlorococcus responds to dynamically shifting nutrient concentrations in the environment. Prochlorococcus is the smallest known oxygen-evolving photoautotroph. However, the smallest photoautotroph is also the most abundant photosynthetic organism on the planet and has been reported to account for 13-48% of gross primary productivity in nutrient-poor oligotrophic oceans. Oligotrophic oceans may experience climate change related increases in nitrogen fixation and subsequent phosphorous limitation; Prochlorococcus likely has a competitive advantage over larger eukaryotic phytoplankton in these phosphorous limited regions which enables them to be the dominant primary producer. My research focuses on how changing nutrient conditions impact Prochlorococcus, and how the response by Prochlorococcus may impact global biogeochemical cycling.

  My graduate studies are funded in part through the receipt of a 2010 National Science Foundation Graduate Research Fellowship. I also remain actively engaged with the Student Conservation Association as an Alumni Council Representative

 For research and school related information, please send me an e-mail at jaclynk at

 For questions regarding my involvement with the Student Conservation Association you can reach me at jaclynsaunders at 

Cedar McKay



I am an engineer here in the lab, and a bit of a jack of all trades. My responsibilities are broken into two main areas.

Much of our work depends on analyzing sequence large streams of data using various computational techniques. New sequencing and proteomics technologies generate enormous amounts of data, which are challenging to process, analyze and store. I work with Gabrielle to link various pieces of software and custom programs together in a way that yields results that are relevant, accurate and informative. I write software as needed for our analysis, usually using the python programming language. 

Systems Administration:

I keep our computers and servers running smoothly, our systems backed up, and hackers out of our hair. I am also responsible for designing the website which you are viewing right now!


I'm an avid cook and photographer. See my cooking website here:

Michele Guannel


Contact information

After receiving her Ph.D. in 2012, Michele joined the Center for Microbial Oceanography: Research and Education (C-MORE) as a Marine Science Educator.  You may contact her at mguannel {AT}


  • B.A. Smith College magna cum laude with Highest Honors in Biological Sciences, 1997.
  • Member of Sea Education Association's SEA Semester, 1996.
  • M.S. University of Washington, Biological Oceanography, 2007.
  • Ph.D. University of Washington, Biological Oceanography, 2012.


 Research: two perspectives

~Oceans and human health~

 My research contributes to the Pacific Northwest Center for Human Health and Ocean Studies, a multidisciplinary collaboration that began at the University of Washington in 2004. A group of oceanographers, public health researchers, and other scientists, we seek to understand one type of harmful algal bloom that occurs in Washington State waters and worldwide. Marine diatoms of the genus Pseudo-nitzschia produce domoic acid, which acts as a neurotoxin in higher trophic level organisms.  Domoic acid causes Amnesic Shellfish Poisoning (ASP) in humans, and neurological disorders and death in many marine organisms, such as birds and sea lions. Domoic acid outbreaks have been documented along the Pacific Coast of Washington since the early 1990s, and more recently in Puget Sound in 2003 and 2005.

Under which conditions do Pseudo-nitzschia produce domoic acid?  Can we apply our understanding of Pseudo-nitzschia distribution and toxigenicity to "forecast" domoic acid outbreaks?  These are two of the broad questions that drive this research.

In 2008, I was awarded an Oceans and Human Health Initiative (OHHI) Pre-Doctoral Traineeship.  The OHHI Traineeship program seeks to develop scientists who communicate across diverse disciplines and direct their research to optimize impacts of the ocean upon human health and well-being.

~Microbial biogeography~

The distribution of organisms is influenced by historical and present-day responses to their environment, whereby environment is defined in terms of physical and chemical features and interactions with other organisms.  I am most fascinated by the "biological environment" that becomes, at any time, ecologically important for a species or group of organisms. I am interested in biogeography from the micro to global scales. How do individual phytoplankton cells create environments that enrich for specific types of bacteria?  Are any phytoplankton truly cosmopolitan, and if so, which factors enable this amazing level of ecological success?

Research: specific projects

~Interactions between bacteria and Pseudo-nitzschia~

Previous laboratory research (e.g. Bates et al. 1995) revealed that, when bacterial isolates are added to Pseudo-nitzschia multiseries cultures, the diatom produces higher levels of domoic acid.  However, the nature of this interaction is not well characterized. To better understand associations between bacteria and Pseudo-nitzschia, I used 16S rDNA sequencing and Automated Ribosomal Intergenic Spacer Analysis (ARISA; a community fingerprinting technique) to characterize bacterial communities coexisting with 18 Pseudo-nitzschia cultures, representing five species.  Bacterial community composition differed significantly according to Pseudo-nitzschia species and toxigenicity. 

These findings could suggest that bacterial communities are influenced by domoic acid or other species-specific features of the Pseudo-nitzschia "phycosphere."

~Community composition of toxigenic Pseudo-nitzschia blooms & Pseudo-nitzschia biogeography~

Compared to our understanding of harmful Pseudo-nitzschia blooms in the Northern Hemisphere, considerably fewer studies describe the distribution and toxigenicity of Pseudo-nitzschia blooms throughout the Southern Hemisphere.  In 2007, I surveyed Pseudo-nitzschia communities and domoic acid levels across the South Atlantic Ocean and northern Benguela Upwelling Zone. I am applying Pseudo-nitzschia ARISA (Hubbard et al. 2008), among other methods, to investigate the composition of these Pseudo-nitzschia communities in relation to known biogeography of the genus.



Teaching is one of my favorite things to do!

~Teaching and community service positions~

  • Biology and chemistry tutor, Smith College, 1996-1997.
  • AmeriCorps Member, National Civilian Community Corps, Perry Point, MD, 1997-1998. I tutored sixth graders (Baltimore, MD) and completed other community service projects throughout the northeastern US.
  • Greenfield AmeriCorps Program Member, Greenfield, MA, 1998-1999. I tutored and mentored middle school students and facilitated extracurricular art and service learning programs for middle and high school age youth.
  • Independent tutor for middle and high school students, Eugene, OR, 1999-2001.
  • Mentor, Seattle Girls' School, 2006-2009.
  • Various outreach activities, University of Washington, 2007-present.  I am particularly interested in outreach to groups underrepresented in the sciences, in order to increase the diversity of our field.

~Teaching assistant positions at UW~

  • OCN 430 Biological Oceanography (undergraduate level), Autumn 2005.
  • OCN 102 The Changing Oceans, Winter 2010.
  • OCN 101 Survey of Oceanography, Spring 2011.
  • OCN 535 Biological Oceanography (graduate level), Autumn 2011.
  • BIOL 250 Marine Biology, Summer 2012.

~Mentorship of undergraduate researchers~

  • Gwendolynn Hannam, 2007-2008.  Phytoplankton and bacterial culturing.
  • Diana Haring, 2008-2010.  Phytoplankton microscopy and molecular methods.



Guannel, M.L., Horner-Devine, M.C., and Rocap, G.  2011.  Bacterial community composition differs with species and toxigenicity of the diatom Pseudo-nitzschia.  Aquatic Microbial Ecology 64: 117-133 

Erdner, D.L., Dyble, J., Parsons, M.L., Stevens, R.C.,  Hubbard, K.A., Wrabel*, M.L., Moore, S.K., Lefebvre, K.A., Anderson, D.M., Bienfang, P., Bidigare, R.R., Parker, M.S., Moeller, P., Brand, L.E., and Trainer, V.L. 2008. Centers for Oceans and Human Health: a unified approach to the challenge of harmful algal blooms. Environmental Health 7:S2.

Wrabel*, M.L. and Peckol, P. 2000. Effects of bioremediation on toxicity and chemical composition of No. 2 fuel oil: growth responses of the brown alga Fucus vesiculosus. Marine Pollution Bulletin 40(2): 135-139.

Wrabel*, M.L.  1997.  Effects of bioremediation on physiological responses of the macroalgae Ascophyllum nodosum, Fucus vesiculosus and Laminaria saccharina exposed to No. 2 fuel oil.  Undergraduate Honors Thesis. Smith College Department of Biological Sciences. 

* former surname: Wrabel

Nathan Ahlgren


Graduate Student 2001-2008

Presently: Postdoctoral Researcher  Dept. of Microbiology, UW

B.S. Biology. Massachusetts Institute of Technology. Cambridge, MA (1999)

M.S. Biological Oceanography. University of Washington. Seattle, WA (2003)

Ph.D. Biological Oceanography. University of Washington. Seattle, WA (2008)

Research interests: Ecology and evolution of marine Synechococcus

Marine Synechococcus provide an excellent model to explore the mechanisms of differentiation in marine bacteria. This abundant group of cyanobacteria is found throughout the world's oceans, in both oligotrophic and coastal regimes and ranging from tropical to polar regions. Their ability to inhabit a wide range of habitats is attributed to the fact that this genus is comprised of several (at least 16) ecotypes--separate populations which which are genetically and physiologically distinct from each other. I am interested in understanding what physiological differences make these ecotypes distinct and the mechanisms that generate and maintain their coexistence.

More specific research interests:

  • the importance of light physiology and nitrogen utilization in differentiation of marine Synechococcus ecotypes
  • the role of periodic selective sweeps in the differentiation of marine Synechococcus ecotypes
  • the distribution of ecotypes in various environments (with depth through the water column and across oligotrophic and coastal regimes)


Ahlgren, N. A. and G. Rocap. 2006. Culture isolation and culture-independent clone libraries reveal new marine Synechococcus ecotypes with distinctive light and N physiologies. Applied and Environmental Microbiology 72: 7193-7204. PDF file (752 kb)

Ahlgren, N. A., G. Rocap, and S. W. Chisholm. 2005. Measurement of Prochlorococcus ecotypes using real-time polymerase chain reaction reveals different abundances of genotypes with similar light physiologies Environmental Microbiology 8: 441-454 PDF file (257 kb)

Rocap, G., F. W. Larimer, J. Lamerdin, S. Malfatti, P. Chain, N. A. Ahlgren, A. Arellano, M. Coleman, L. Hauser, W. R. Hess, Z. I. Johnson, M. Land, D. Lindell, A. F. Post, W. Regala, M. Shah, S. L. Shaw, C. Steglich, M. B. Sullivan, C. S. Ting, A. Tolonen, E. A. Webb, E. R. Zinser and S. W. Chisholm. 2003. Genome divergence in two Prochlorococcus ecotypes reflects oceanic niche differentiation. Nature 424: 1042-1047. PDF file (430 kb)
Supplementary Information (418 kb)

Mann, E. L., N. Ahlgren , Moffett, J. W., Chisholm, S. W. (2002) Copper toxicity and cyanobacteria ecology in the Sargasso Sea. Limnology and Oceanography 47(4): 976-988. PDF file (300 kb)

Gabrielle Rocap

Gabrielle Rocap

Principal Investigator



  • Ph.D., Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, Biological Oceanography, 2000. 
  • S.B., Massachusetts Institute of Technology, Biology, 1992.

Positions Held

  • Associate Professor, School of Oceanography, University of Washington, 2007-present
  • Associate Director, School of Oceanography, University of Washington, 2007-2010
  • Assistant Professor, School of Oceanography, University of Washington, 2001-2007
  • Post-Doctoral Research Associate, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology 2000-2001
(clink link above for full list with pdfs)


Hit reload to see all three glorious pictures!

Join our hip lab!

As an undergraduate student...
We have several ongoing projects suitable for undergraduate research topics. Interest in or experience with either molecular biology or computational biology is a plus but certainly not a requirement.  Past undergraduate researchers have had a variety of academic majors including Oceanography, Microbiology, Biology, SAFS, and Applied and Computational Math Sciences.  Students generally work for academic credit for at least one quarter before paid positions are available. Please contact me directly to talk about your interests. 

As a graduate student...
See the instructions for graduate study in the School of Oceanography. I also encourage you to contact me directly to discuss your interests and to apply for any of the following graduate student fellowships you may qualify for (this is good advice no matter where you end up!).

As a post-doctoral research scientist... 
There are currently no externally funded post-doc positions available. Candidates interested in applying for post-doctoral fellowships or collaborating on new proposals are encouraged to contact the PI directly to discuss their experience and interests.
Syndicate content