By Mr. Patrick Moes (USACE)August 30, 2012
As Asian carp continue to dominate news headlines across the Upper Mississippi River, St. Paul District scientists recently received some new technology to assist them in researching fish on the river.
Elliot Stefanik, biologist, said the Rock Island District lent a hydroacoustic camera to the St. Paul District in March to study fish within the river. The camera uses underwater sound waves and a computer then translates those waves into images in real time. "It's almost like an ultrasound or
side-scan sonar technology used by fishermen," said Stefanik.
While the technology is providing the Corps biologists' valuable research, Stefanik said the equipment is limited in terms of what they see. He said they can't see colors or defined shapes and that limits the researchers in determining what fish are present, but he said they can still observe fish behavior. "We observe how fish are acting, how they orient, and we can gain a lot of information," said Stefanik.
Many of the Corps' partners are currently exploring options to prevent the spread of Asian carp into Minnesota waters. Currently, the state of Minnesota has expressed interest in building a barrier in front of a lock and dam to discourage fish from entering the lock chamber. Stefanik
said he hopes the information the Corps collects can be used by the partners in designing a fish deterrent system.
"We hope to get a better understanding of how fish are behaving around our locks and then provide that [information] to our partners, so they know how many fish are using the lock chamber and how they behave in the chamber," said Stefanik. "It's all about being a good partner and helping other agencies better understand and better characterize how fish respond to a lock and dam structure."
During the June 7 research at Lock and Dam 1 in Minneapolis, Stefanik said there was a large amount of common carp near the lock and dam. "We see a lot of common carp around this time of year, especially when the water temperatures get around 70 degrees," he said. "While
common carp may behave slightly different from Asian carp; they may be the best proxy the Corps has to determine how Asian carp might behave around a lock and dam." He said the Corps is also studying common carp within the Chicago Area Waterway System to determine
how they behave around the electrical barrier.
Moving forward, Stefanik said the next step in the research process will be taking the information they collected and looking at it collectively with the different agencies to see if there is anything that they can gather from it in terms of general fish tendencies.