Asian carp are threatening to take a huge toll on the Great Lakes ecosystem, but instead of working to solve the problem, the federal government is proposing costly short-term plans that will not make any difference.
The Great Lakes are on the verge of being invaded by hostile marauders, and the federal government wants to throw money at studying the invasion, rather than taking bold steps to prevent it. Bighead and silver carp, fish that are native to Asia, have been slowly making their way toward the Great Lakes since the 1970s, when they escaped from fish ponds and sewage treatment plants in the Deep South. The largest of the carp can reach 4 feet long and 100 pounds, and every day can eat up to 40% of their body weight in plankton, which is the foundation of the food chain in rivers and lakes. Asian carp have already taken over parts of the Illinois and Mississippi rivers, where they have driven away many of the native fish. Silver carp have been known to hurl out of the water when they hear motors passing by, slamming their bodies into boaters and water skiers with bone-shattering force.
If the huge fish are able to establish themselves in the Great Lakes, they could quickly starve out the smaller prey fish that salmon and whitefish depend on, which would then decimate the populations of those game fish. Scientists disagree about whether or not the carp can survive in the Great Lakes because the water is colder, deeper, and of a different ecological system than the systems in rivers. But most people believe the risk is too great to make any assumptions. There is only one way to find out what the impact of a full-on invasion of the carp would be, and no one wants the threat to get to that point.
The most certain way to prevent the fish from taking over the lakes and thereby threatening the $7 billion Great Lakes fishing industry is to block the link between the Mississippi River basin and Lake Michigan, which was created more than a century ago by engineers in Chicago. But the Obama administration’s strategy, recently released, proposes only a long-range study of that solution. The study could take years, and the government’s battle plan has a price tag of $78.5 million.
In addition, the government is refusing to close down two navigational locks on waterways in Chicago which may give the carp an easy access to the lakes. The government promises to "consider" opening the locks less often, but for now they remain open indefinitely. Environmentalists and governors claim that closing the locks is the best short-term solution, but it is far from foolproof, since younger carp may still be able to slip through the weathered structures.
Instead of a firm strategy for thwarting the invasion, the government’s plan details two dozen other ideas, such as strengthening a barrier to electronically block the advance of the fish, or using poisons or nets to catch any fish that make their way through. The plan relies heavily on technology, such as using sound, bubble curtains, and strobe lights in barriers to repel the carp, as well as preventing them from reproducing through biological controls.
The proposals are an expensive gamble, and they may not result in keeping enough of the marauders out of the lakes to avoid a devastating invasion. Joel Brammeier, president of the Alliance for the Great Lakes, says that the government wants to spend nearly $80 million for just a short-term deterrent. "We need to stop pushing money toward temporary solutions and get everyone on track toward investing in one that works for good," Brammeier says. "And that means absolute physical separation."
Cutting the ties between the Mississippi and the Great Lakes would require the reconfiguration of about 70 miles of rivers and canals, so it wouldn’t be a simple fix. Such a massive project could not be undertaken quickly, and is vehemently opposed by the barge operators who are responsible for moving millions of tons of goods each year through the locks in Chicago. So the Obama administration says that it is more realistic to confront the marauders on multiple fronts rather than spending the time and money to sever Lake Michigan from the river. And the EPS says that engineering alone is not the answer to fighting biology. So there is definitely a division in opinions about whether to sever the two waterways.
The Army Corps of Engineers has already erected a two-tiered electrified barrier inside the Chicago Sanitary and Ship Canal, which is about 25 miles from Lake Michigan. The barrier emits pulses of electricity to frighten the carp or to knock them unconscious if they keep moving forward. Biologists haven’t found any carp above the barrier so far, but their DNA has been detected in numerous spots past the barrier and even in the lake itself, which means that at least some of the fish have gotten past the device to reach the lake.
The government wants to pour money into stopgap measures such as trying to prevent the fish from breeding. But scientists feel that the only permanent solution is to separate both bodies of water to keep their ecosystems intact. And while everyone is arguing about how to deal with the problem, the fish are swimming.
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