Because carp are known to jump, Suski was prepared for the possibility that the carp would try to jump out of the shuttle box to escape the carbon dioxide. "We covered the tanks to keep them contained, but they didn't jump," he said.
Suski also conducted an experiment on a larger scale in a small, outdoor pond about 40 feet by 30 feet but without fish. "We wanted to see how easy it would be to put CO2 into a lot of water," Suski said. "As it turned out, it's shockingly easy. We did it with a hose and a gas source and just bubbled it in."
Suski said the next step will be to test it in the field on a larger scale, determining the costs and the effect it may have on non-target species and on the environment. The elevated CO2 makes the water slightly more acidic so Suski wants to learn how the higher acidity affects fish, the water, and other organisms.
"What we're working on right now is seeing how effective CO2 is on small fish," Suski said. "In theory, CO2 could eliminate all fish from an area, regardless of their size, whereas we know that for small fish, 1 to 3 inches, the electrical barrier becomes less effective. If smaller fish don't like the CO2 and choose to swim away, that's a potential shortcoming of the electrical barrier that CO2 can address."
According to Suski, Asian carp grow rapidly and totally disrupt the food chain. All fish depend upon zooplankton (small animals) and phytoplankton (small plants) when they are very small. "Asian carp eat these items that the other fish and other aqua
|Contact: Debra Levey Larson|
University of Illinois College of Agricultural, Consumer and Environmental Sciences