Ravenous, Leaping Asian Carp Poised to Invade Great Lakes

By Brett Israel | November 23, 2009 4:30 pm

asian-carpThe Great Lakes are under threat from an Asian carp invasion that could wipe out fishing stocks, and with it, the lakes’ billion dollar fishery. On Friday, officials from the Army Corps of Engineers reported that genetic material from the carp had been found for the first time in a nearby river beyond an elaborate barrier system, which has cost millions of dollars and was meant to block their passage [The New York Times]. There is concern that if carp make it into Lake Michigan, they will gobble up the plankton that native fish feed on.

Officials also say that recreational boating may be affected–the carp can grow up to 4 feet long and weigh up to 100 pounds, and the massive fish will occasionally leap up and strike boaters. Since they were found to be moving up the Mississippi River in 2002, agencies have been trying everything they can think of to slow them down, including erecting the expensive electric barriers that cost around $9 million. The barriers work by sending low-voltage electric current through steel cables that are strung across the canal; this creates an electric field that’s uncomfortable for the fish and that’s supposed to prevent them from swimming across it.

No one has actually spotted any carp on the far side of the underwater electric fence, but new tests let scientists detect the DNA of fish in a river or lake without actually seeing them. Fish have to pee and poop, too, and epithelial cells sloughed off from their bodies showed that Asian carp were in the Chicago Sanitary and Ship canal last month above an electrical barrier that was supposed to keep them out of the Great Lakes [Detroit Free Press]. If the carp have indeed passed through the barrier, that means only a single lock, which regularly opens to allow ships to pass, separates the carp from the world’s largest freshwater reserve. The only non-threatening explanation for the DNA is that carp feces or eggs could have been carried across the barrier by ship and barge traffic. The carp DNA was found as close as eight miles south of Lake Michigan and one mile south of the last shipping lock.

Ironically, the fish were originally imported to help Southern fish farmers fight algae-filled ponds in the 1970s. By the 1990s, flooding had pushed them into the mighty Mississippi and they began swimming north. Joel Brammeier, acting president of the Alliance for the Great Lakes, said “this is an absolute emergency” [The New York Times], because if the carp move past the last lock, there will be no stopping them.

Brammeier is calling for the last lock to be closed and all shipping traffic into Lake Michigan to be halted. The U.S. Army Corps of Engineers said it and other agencies had met since Wednesday to consider the best course of action. Authorities will be sampling the channel to try to locate any loose carp [AP]. Since rivers and lakes are very different ecosystems, scientists can’t say for sure how well the carp would survive if they make it to the Great Lakes. But a worst case scenario has them spreading like a cancer–a doomsday scenario for a region already weakened by invasive species such as zebra mussels.

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Image: U.S. Fish & Wildlife Service

  • Will

    Is it not possible for the DNA to have migrated due to water currents etc?

  • http://clubneko.net Nick

    re: Will – generally not upriver.

    This is evolution in action, folks. Accidents like this is how one type of animal becomes a dominant life form – humans may have accelerated the change through our own foolishness but to expect these ecosystems to remain the same forever is really quite silly.

    There is no way we’ll be able to keep those fish out. Just no way.

  • Mike

    They will ruin the lakes. This is what they have to do in Big Bear Lake in Cali….which is actually pretty eutrophic and nasty do to the fish, too many people, etc. If they invade, they might produce a whole new industry in keeping their levels in check in the Great Lakes.

    With a face only a mother could love, the carp is considered a nuisance. The fish destroys habitat for other species. With its voracious appetite carp devours aquatic vegetation, insects and small crustaceans.

    Mr. Carp meet your newest enemy, Larry Hollingshead. Hollingshead is a retired commercial fisherman and owner of Nevada Carp Company.

    Since 2004 the MWD carp round-up netted more than 16,000 pounds of carp from Big Bear Lake, most by bow fisherman. The fish found their final resting place in a Christmas tree farm. However the round-up is not enough to control the carp population.

    The Big Bear Municipal Water District board has contracted with Nevada Carp Company to help do the job. Hollingshead said his company can remove as much as 5,000 pounds of carp a day. He uses skills learned in Alaska to hunt down the pig of freshwater fish. Hollingshead uses soft netting to round up the carp. Other species will get caught in the net, but those fish will be returned to the water, he said. The carp will go to a landfill.

    Hollingshead’s removal efforts will last 30 days. After 20 days, the MWD will judge Hollingshead’s effectiveness. If successful, Hollingshead will complete the 30-day program and may return annually for the next five years.

  • http://www.kadambari.net Bhaskar

    Carp feed on Blue Green Algae (cyanobacteria), hence survive and grow in eutrophic waters.
    Reducing cyanobacteria blooms is one way to control carp.

  • blue gill

    How about cranking up the power on that electric barrier so the fish rather than being uncomfortable are dead. Or chop up the southern fish farmers that came up with this scheme and feed them to the ravenous carp.

  • Pamela

    “Or chop up the southern fish farmers that came up with this scheme and feed them to the ravenous carp.”

    That get’s my vote!

  • Brian Too

    Have you seen footage of prime carp habitat? They don’t “occasionally jump.”

    It’s actually dangerous to drive a boat through those waterways. The carp jump at noise and disturbance and they can easily jump right over a small watercraft. I’ve seen video of places where the carp are jumping so actively it’s like a thin flock of birds. The people in the boats have to protect their heads and bodies because they will get whacked by a good size fish and they approach from all sides and angles.

  • Darren Garrison

    Simply release wave after wave of Chinese needle snakes.

  • Cubs in 2012

    How many fish have died down stream since we redirected the Chicago River? Our sewage would have killed Lake Michigan by now, instead of contributing to the death of the Gulf of Mexico. Its ironic that the only fish capable of thriving in Chicago Rivers soup, swam thru it, on the way to destroy the Lake we are saving from it.

  • Ken

    The carp are just another example of attempting to cure a problem by the introduction of species without the understanding of the interactions with the other species and natural predators in their native biosphere that kept them controlled. There are many instances of this simplistic though logical action based on ignorance, e.g., the mongoose cure to the Hawaiian rat problem: http://www.perlgurl.org/archives/2006/05/the_mongoose_a_maui_menace_1.html

    And there are many other instances:

    It’s just unfortunate that it takes problems to wake us to the cause and it’s so often too late for an easy cure.

  • JIM

    It’s ironic how the government screws up everything that it touches, but we still want them to jump in and save us from ourselves. God save us from the Asian Carp and Healthcare, because Uncle Sam cannot, and willnot.

  • http://sites.google.com/site/stopkilling4profit/ StopKilling4Profit

    Reading the article, one must ask themself if the author is biased? Using language such as “invasive” and “ravenous”,etc. is done with the intention to make the reader feel that something terrible is happening. The only thing what is happening is evolution. There are no invaders in animal kingdom. The “unwanted” fish species have been introduced into lakes and rivers by man at one time when profit-oriented “tinkering” with the environment became a fashion. This is not about protectionism, but capitalism. As soon as the “good life” of years of angling in paradise is at stake, governments and commercial industry cry wolf and demand the problems to be dealt with.
    The environmental groups who are working with agencies and the army, support only mechanical means to keep the carp away. There are a number of news articles on this particular story and it seems that the media only cares to write about issues of some sentational value. Most authors couldn’t care less to dig deeper in their research in an effort to understand the criteria. Fact is that “you can’t push a river – you have to go with the flow…” Learn more about the hazards of chemical lake restorations: http://sites.google.com/site/stopkilling4profit/

  • http://philbs0qzi.tumblr.com/ Zack Gilb

    The open water fishing is ok in this part but does anyone have some suggestions on any decent rivers to find some good fishing,especially looking to find good numbers of flying carp,a few other guys have caught some great catches lately.

  • Granny

    Are they edible, if so, bring them on, i do not think the MNR can control me catching them in a net when they leap out of the water or would they be considered road kill if they land in my boat.


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