Thursday, February 2, 2012

New Plan To Stop Carp Infestation

With Asian carp set to ravage the Great Lakes, the federal government has devised a 78.5 million dollar plan that cannot promise to fend off the predators, and does not utilize the most powerful weapon in its arsenal, the Associated Press reported.

The most promising method to keep the carp from wreaking havoc in the lakes and threatening its $7 billion fishing industry is to cut the link between Lake Michigan and the Mississippi River basin, which was built by engineers in Chicago over 100 years ago.

The plan, announced by the Obama administration this week, only commits to conduct a long-range study of that theory that could take years. The government said it will consider opening two navigational locks on Chicago waterways less often, but refuses to close it down completely to keep the carp from entering the lakes.

The plan outlines two dozen other steps instead. One of the steps is to strengthen an electric barrier created to keep the carp from passing through with nets or poisons. Such measures are not fool-proof and may not be able to block enough carp from plaguing the lakes. 

 "We’re spending close to $80 million just for a short-term deterrent," Joel Brammeier, president of the Alliance for the Great Lakes, told AP.

"We need to stop pushing money toward temporary solutions and get everyone on track toward investing in one that works for good “” and that means absolute physical separation."

The preferred method would be a massive undertaking. To cut the ties between the lakes and the Mississippi would involve the reconfiguration of around 70 miles of canals and rivers. It would also take time, and barge operators are not in favor of losing their passageway as they transport millions of tons of commodities through the Chicago locks yearly.

The concern about the carp situation is substantiated. Bighead and silver carp, both native to Asia, have been migrating toward the lakes ever since they escaped Deep South fish ponds and sewage treatment plants in the 1970s. At its largest, carp can reach 100 pounds and 4 feet long, consuming up to 40 percent of their body weight daily in plankton.

If the carp get a foothold in the lakes, they could starve the prey fish on which popular fish like salmon and whitefish depend.

They have already overwhelmed parts of the Mississippi and Illinois rivers, driving away many native fish.

Though scientists may dispute whether the carp would thrive in the Great Lakes, which are colder, deeper and ecologically different than rivers, many believe the risk is too great to gamble.

"None of us know for certain what their impact would be," University of Notre Dame biologist David Lodge told a House subcommittee this week. "There’s only one way to find out, and I don’t think any of us want that."

The Obama administration says the only practical way to deal with the issue is to confront the carp on multiple fronts rather than severing Lake Michigan from the Mississippi basin.

"We cannot fight biology with engineering alone," Cameron Davis, the Environmental Protection Agency’s spokesman on the issue, told the congressional panel.

However, the federal plan is full of technological innovations, including barriers using sound, strobe lights and bubble curtains to repel carp and biological controls to prevent them from reproducing.

Great Lakes governors and environmentalists outside of Illinois wanting to close the Chicago locks say it is the most viable short-term option, but it still allows the possibility for carp to sneak through leaky structures. The Chicago waterways also have other access points to Lake Michigan.

Army Corps of Engineers officials are banking on a two-tiered electric barrier in the Chicago Sanitary and Ship Canal about 25 miles from Lake Michigan. It sends out pulses to ward off the carp or knock them unconscious if they do not turn around. Though no carp have been discovered above the barrier, biologists have found their DNA in several spots past it and even within the lake itself.

"While we’re all talking," Lodge tols AP, "the fish are swimming."
This seems to indicate that at least some carp have snuck by the device and entered the lake. The government’s plan is designed to keep their numbers low enough to ensure they do not reproduce. 

Unfortunately, no one knows how many carp would have to reach the lake to establish an irreversible foothold.

"This is a lot of money to pile into stopgap measures," said Phil Moy, a University of Wisconsin Sea Grant researcher. "It may do some good in the short term, but in the long term it’s not going to solve the problem of invasive species on both sides of the divide.  Ecological separation has to happen for this to be successful." 

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