|Carp eggs might hitch ride past fence, enter Lake Michigan|
|Written by Chicago Sun Times|
|Sunday, 06 March 2005 11:04|
Even if adult Asian carp don't get into Lake Michigan, their eggs will.
Female carp will spill millions of eggs into the Chicago Sanitary & Ship Canal in late June or July, aquatic biologists say.
Barges will pump canal water containing eggs, some hatched into larvae, into ballast tanks to level their loads. And when the boats deliver their cargoes to Lake Michigan ports, the ballast water -- along with the eggs and larvae -- will be dumped into the lake.
This is another way the destructive invader fish will circumvent the $9.1 million electrified barrier being built in the canal, warns longtime Great Lakes advocate Eddie Landmichl of Chicago.
Landmichl, president of Perch America, figured out last December that the barrier might not work. He argued that carp will make their way into the canal upstream of the barrier from the nearby Des Plaines River if there is a good-sized flood. The Army Corps of Engineers said he could be right.
Now Landmichl has discovered a second reason to oppose the barrier. "What good is the barrier if we're going to let barges carry the eggs and young fish through the barrier and into the Great Lakes?" he said.
The voracious exotics, which devour food needed by native fish, threaten the lakes' $4.5 billion sport and commercial fishing industry. To halt their advance up the Illinois River before they reach Lake Michigan, the Corps installed a temporary barrier at Romeoville in 2002 and is at work on a permanent one at Lemont.
By calling attention to the egg-transfer problem, "Eddie has certainly raised a valid concern," said Roger Klocek, conservation biologist at the Shedd Aquarium. "It's something nobody else thought of."
Klocek referred detailed questions to Mark Pegg of the Illinois Natural History Survey, who runs an Illinois River station at Havana. "I never thought about it," Pegg said.
But Pegg, who last summer found more than 2.2 million eggs in one 42-pound Asian carp, said tumbling through barge pumps probably would destroy eggs and larvae. So did Scott Stuewe, acting fisheries chief of the Illinois Department of Natural Resources. But Stuewe added, "It's always possible some would survive."
Landmichl, 70, worked on barges as a younger man and responded, "Many if not all of the pumps will pass 'em through."
David Jude of the University of Michigan at Ann Arbor agreed. "Those eggs are practically bulletproof," he said.
Jude is the researcher who identified the first round goby in this country. Native to Europe, those nuisance fish also got into the Great Lakes via ships' ballast water.
The carp, Chinese imports that escaped from Arkansas fish farms into the Mississippi River and then entered the Illinois waterway, will use ballast water as their ticket to the Great Lakes, he said.