Keep Fishin’ – Hobart and William Smith Colleges \
The HWS Update

Keep Fishin’

Assistant Professors of Biology Meghan Brown and Susan Cushman ’98 noticed something fishy going on in the ponds on the Colleges’ 108-acre Hanley Preserve-literally. Though the two ponds they are studying share a similar history and are only located a few hundred yards apart, they’re home to drastically different microscopic aquatic organisms. The biologists want to figure out why. “We’re playing detective,” explains Brown. “The ponds’ shapes are virtually identical, and their nutrient chemistries are the same, but the size and species of plankton are completely different. We’re hypothesizing that it’s because of different fish assemblages.” The researchers are taking samples from multiple depths in both of the ponds and measuring levels of nutrients like nitrogen, phosphorus and pH, as well as the amount of light, dissolved oxygen and the temperature of the water. They are also collecting samples of zooplankton by towing nets through the water. Later, the team returned to seine the ponds to characterize fish populations. Both ponds under investigation were originally dug for recreational fishing by Henry Hanley in the 1960s and are the deepest of the 60 on the Hanley property. “We think that the large concentrations of sports fish – fish-eating fish – in Pond 11 are lowering the abundance of forage, or plankton-eating, fish. This means that zooplankton, the prey of the forage fish, are abundant, and the zooplankton’s prey, the phytoplankton or algae, are rare,” says Brown. “That’s a good thing, since it means that the water is clearer and cleaner,” explains Cushman. The biologists think the opposite is true for Pond 7; few predators at the top of the food web generate lots of phytoplankton at the base of the food web. Brown and Cushman are working with several student researchers, including Cameron Avelis ’11, a biology major who became interested in aquatic biology after taking Brown’s Exotic Species course. “I did similar research out on Seneca Lake and wanted to continue with it this summer,” he said. “We hope that research will not only continue this fall, but for years to come,” said Brown, who has been studying the ponds since her arrival at HWS. “The property is a wonderful site. It’s accessible and meaningful for students to study.” Brown holds a B.S. from the University of Michigan and received her master’s and Ph.D. from the University of Minnesota. Before joining Hobart and William Smith Colleges in 2004, she taught and conducted research for the U.S. Environmental Protection Agency, The National Park Service, and the Istituto per lo Studio degli Ecosistemi in Pallanza, Italy. Cushman received a B.S. in biology with honors from William Smith College, a M.S. in environmental sciences from Johns Hopkins University and a Ph.D. in marine, estuarine and environmental studies from the University of Maryland. She is currently involved with the Cayuga Lake Watershed Network Issues Committee and specializes in fisheries science, specifically fish and stream ecology.