Peggy H. Ostrom


Ph.D., Memorial University of Newfoundland, 1990

236A Natural Science Building
Office Telephone: 517-353-9768

Biogeochemistry and Food Web Dynamics

My primary research interests are in the fields of biogeochemistry and food web dynamics.  Our lab is nationally recognized for its work using stable isotopes as natural tracers in the ecosystems. We focus on a variety of modern and past ecosystem issues ranging from conservation of endangered species and trace gas flux. Currently, I am funded to use genetic and stable isotope approaches to study the foraging ecology and genetic history of the endangered Hawaiian Petrel and threatened Newell's Shearwater. These seabirds have a stunning life history, spending only a few months each year on their breeding sites in the Hawaiian Islands. In the past, the Hawaiian Petrel was said to "darken the skies" but now they are isolated to a small number of colonies at high latitude that are at risk from predators (e.g. feral cats and rats), invasive vegetation and human disturbances. A developing project focuses on the foraging biology, food web and conservation issues associated with bottlenose dolphins resident to Sarasota Bay, Florida. In collaboratoin with Dr. Randall Wells, Dr. Nelio Barros and Dr. Craig Stricker we seek to understand the influence of anthropogenic perturbations on the ecology of these dolphins. In collaboration with Dr. Nathaniel Ostrom, my research efforts are directed at understanding the origins and flux of the greenhouse gas, nitrous oxide. Nitrous oxide, with a greenhouse gas potential 300 times greater than that of carbon dioxide, is poorly understood. yet, we have developed an approach to apportion the orgins of nitrous oxide between nitrification and denitrification. Our efforts will help to deliver important information to policy makers attempting to mitigate global climate change.

Also see project website, by Matt Cimitile:

Exploring the Past to Save the Future

Representative Publications

Wiley, A., P.H. Ostrom, C.A. Stricker, H. James, and H. Gandhi. Submitted. Isotopic variation within feathers: Implications and sampling strategies. Rapid Communications in Mass Spectrometry.

Barros, N., P.H. Ostrom, C.A. Stricker, R.S. Wells. Accepted. Stable isotopes differentiate bottlenose dolphins of west-central Florida. Marine Mammal Science.

Jinuntuya-Nortman, M., R.L. Sutka, P.H. Ostrom, H. Gandhi, and N.E. Ostrom. 2008. Isotopologue fractionation during microbial reduction of N2O within soil mesocosms as a function of water-filled pore space. Soil Biology & Biochemistry 40, 2273-2280.

Kaplan, L.A., T.N. Wiegner, J.D. Newbold, P.H. Ostrom, and H. Gandhi. 2008. Untangling the complex issue of dissolved organic carbon uptake: a stable isotope approach. Freshwater Biology 53, 855-864.

Humpula, J.F., P.H. Ostrom, H. Gandhi, J.R. Strahler, A.K. Walker, T.W. Stafford Jr., J.J. Smith, M.R. Voorhies, R.G. Corner, and P.C. Andrews. 2007. Investigation of the protein osteocalcin of Camelops hesternus: sequence, structure and phylogenetic implications. Geociminca et Cosmichimica Acta 71: 5956-5967.