The tricky part is estimating how damage to one group of organisms might affect others above or below it in the food chain. Ocean ecosystems are extremely complicated and poorly understood. Phytoplankton concentrations may not be the main factor influencing, say, krill abundance, which also depends on ocean currents, predator-prey relationships, and the timing and extent of annual sea ice. Krill live in areas usually affected only every few days by the wobbling ozone hole. It's too early to tell.
Scientists studying UV effects on different portions of the food chain now collaborate closely.
Here aboard the National Science Foundation's ice-going research ship Laurence M. Gould, four separate teams coordinate experiments and sampling to begin teasing out relationships between effects on ocean chemistry, bacteria, phytoplankton, fish larvae, and krill. But it's not clear how much is caused by direct UV damage to the bacteria's DNA, as opposed to indirect damage from the way UV changes the chemistry of sea water. So his team works closely on ship with chemical oceanographers Kenneth Mopper of Washington State University and David Kieber from the State University of New York College of Environmental Science and Forestry, in Syracuse. Surface waters are laden with dissolved organic matter, from which UV can produce hydrogen peroxide and other substances hazardous to living tissues. UV may harm bacteria during short-term exposures, but that could be compensated for by increased food sources over the long haul.