Steven Baer, PhD

Postdoctoral Scientist
Marine Biogeochemist
Phone: +1 (207) 315-2567, ext. 401
Fax: +1 (207) 315-2329

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B.A., Social Thought & Political Economy, University of Massachusetts, Amherst

Ph.D., Chemical Oceanography, Virginia Institute of Marine Science, College of William & Mary

Research Interests

I am interested in biogeochemical cycling of the macronutrients carbon, nitrogen, and phosphorus, and how different nutrient regimes impact microbial ecology and diversity. Traveling to far-flung locales and working on ships has been an amazing adventure. I have worked in a wide variety of environments, including the coastal Arctic and Antarctic, the open ocean areas of the North Atlantic, equatorial Pacific, and eastern Indian Oceans, and the more coastal areas of Chesapeake Bay and the Gulf of Mexico.

In the lab, I use a variety of techniques to understand the flow of nutrients among different phytoplankton groups. In addition to stable isotope tracers, I use a flow cytometer to both elucidate and sort microbial populations, focused on the ubiquitous open ocean cyanobacteria Prochlorococcus and Synechococcus. Recently, I’ve expanded my view to organisms larger than a few microns, working with a FlowCAM to assess eukaryotic phytoplankton groups. Additionally, I have begun doing manipulative experiments on polar diatom cultures. All of these different techniques provide opportunities for me to answer the driving questions of my research; namely, what are the major phytoplankton groups, and what are their activities? My aim is to use this information to better understand the flow of carbon through the marine food web, both now and in the future.

I have taught Arctic oceanography at the College of William & Mary, a chemistry lab at Christopher Newport University, and introductory marine science to Colby College students while here at Bigelow Lab. Working with undergraduates has been a great opportunity to educate and inspire young scientists.

SE Baer Recent Publications


  • Wawrik B, Bronk DA, Baer SE, Chi L, Sun M, Cooper JT, Yang Z (accepted) Bacterial utilization of creatine in seawater. Aquatic Microbial Ecology.
  • Sipler RE, Gong D, Baer SE, Sanderson MP, Mulholland M, Bronk DA (accepted) Preliminary estimates of the contribution of Arctic nitrogen fixation to the global nitrogen budget. Limnology and Oceanography Letters.
  • Baer SE, Sipler RE, Roberts QN, Yager PL, Frischer ME, Bronk DA (in press) Seasonal nitrogen uptake and regeneration in the western coastal Arctic. Limnology & Oceanography.
  • Baer SE, Lomas MW, Terpis KX, Mouginot C, Martiny AC (in press) Stoichiometry of Prochlorococcus, Synechococcus, and small eukaryote populations in the western North Atlantic Ocean. Environmental Microbiology.
  • Sipler RE, Baer SE, Connelly TL, Frischer ME, Roberts QN, Yager PL, Bronk DA (in press) Chemical and photophysiological impact of tundra derived humic acids on nitrate uptake in the coastal western Arctic. Limnology & Oceanography.
  • Singh A, Baer SE, Riebesell U, Martiny AC, Lomas MW (2015) C : N : P stoichiometry at the Bermuda Atlantic Time-series Study station in the North Atlantic Ocean. Biogeosciences, 12: 6389-6403.
  • Baer SE, Connelly TL, Bronk DA (2015) Nitrogen uptake dynamics in Arctic landfast sea ice near Barrow, Alaska during winter and spring. Polar Biology 28: 781-797.
  • Baer SE, Connelly TL, Bronk DA, Yager PL (2014) The effect of temperature on rates of ammonium uptake and nitrification in the western coastal Arctic during winter, spring, and summer. Global Biogeochemical Cycles 28: 1455-1466.
  • Connelly TL*, Baer SE*, Cooper JT, Bronk DA, Wawrik B (2014) Urea uptake and carbon fixation by marine pelagic Bacteria and Archaea during the Arctic summer and winter seasons. Applied and Environmental Microbiology 80(19): 6103-6022.

  • * These authors contributed equally.

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