Hannes Baumann, assistant professor of marine sciences, specializes in research on how fish populations are adapted to natural variability in their environment and how they react to ongoing anthropogenic changes in the oceans and coastal waters. These include changes in pH (ocean acidification) and temperature (global warming), but also man-made alterations to the marine food web (fisheries exploitation) and natural mortality patterns (selection).
This summer, with funding from the National Science Foundation, Baumann and his team are conducting research on seasonal changes in spawning and offspring sensitivity in the Atlantic Silverside (Menidia menidia). The Atlantic Silverside is an inconspicuous but ecologically important fish that spawns in saltwater marshes and comprises one of the most abundant food sources for striped bass, bluefish, yellowtail flounder, and others along the American east coast.
In order to study the sensitivity of the very young fish to low pH and low oxygen, caused by climate change and excess nutrients in the water, the researchers obtain embryos from fish caught in the wild and raise them in the lab. They also produce Silverside offspring in the lab by strip-spawning males and females and then counting the eggs.
Graduate student Chris Murray is studying the sensitivity of offspring to the separate and combined effects of high CO2 and low oxygen. REU student Elle Parks is looking at the effects of CO2 and temperature on the starvation resistance of silverside larvae.
Together with Baumann, graduate student James Harrington is rearing fish in collaboration with colleagues from Cornell University, for purposes of genetic studies. Their goal is to develop an annotated genome of the species, which will assist in understanding the molecular and genetic responses of the organisms to local selection regimes and marine climate change.