Asian carp could make up one-third of combined fish weight in Lake Erie: study

TRAVERSE CITY, Mich. -- Asian carp could become the most common fish in Lake Erie if the ravenous invaders develop a breeding population there, while popular sport species including walleye and rainbow trout likely would decline, scientists said Monday.

See Full Article

A newly published study based on computer modeling projected that bighead and silver carp, which are Asian carp species, eventually could make up about one-third of the total fish weight in Erie, which has the most fish of the five Great Lakes even though it's the smallest by volume.

"They would be quite abundant," said Ed Rutherford, a fisheries biologist with the federal Great Lakes Environmental Research Laboratory in Ann Arbor and a member of the study team, which included scientists from several U.S. and Canadian universities and government offices.

The carp, which have overrun the Mississippi River and many of its tributaries since being imported to the southern U.S. from Asia in the 1970s to cleanse sewage treatment ponds, gorge on tiny plants and animals known as plankton that all fish eat at some point in life. They are migrating northward toward the Great Lakes, where agencies have spent more than $300 million to keep them out.

A few have been found in Lake Erie over the years, and some samples of its waters have tested positive for Asian carp DNA. But there is no evidence that it has self-sustaining populations of silver or bighead carp.

Even so, the study's findings underscore the significance of the threat, said Marc Gaden, spokesman for the Great Lakes Fishery Commission, a U.S.-Canadian agency.

"It's very sobering," Gaden said. "Lake Erie is one of the most productive inland fisheries in the world. It wouldn't be as valuable by any stretch of the imagination if one out of every three pounds of fish were Asian carp."

The study used an ecosystem modeling program and consultation with experts to estimate how Asian carp, which can weigh dozens of pounds and eat up to 20 per cent of their body weight daily, would affect Erie's food chains.

It found they would pose stiff competition for other plankton eaters, including gizzard shad and emerald shiners, two of the lake's most important prey fish. The emerald shiner population could drop by as much as 37 per cent. Adult walleye, a prized sport species, could decline by 10 to 15 per cent.

Not all native fish would fare poorly, said Hongyan Zhang of the University of Michigan, the report's lead writer. Ironically, Asian carp could give adult yellow perch a slight boost by driving down numbers of white perch, which feed on yellow perch larvae. Smallmouth bass could be another winner because their primary food source is round goby, which Asian carp don't eat.

The study was published last week in the journal Transactions of the American Fisheries Society. The research team plans similar modeling of potential Asian carp effects on Lakes Michigan, Huron and Ontario.


Latest Tech & Science News

  • Alien contact? Don't jump the gun: Bob McDonald

    Tech & Science CBC News
    According to two astronomers from Quebec, unusual signals coming from 234 sun-like stars suggest that alien civilizations could be reaching out for contact. If true, this would have a profound effect on our understanding of our place in the universe. Source
  • SpaceX closer to understanding rocket explosion at pad

    Tech & Science CTV News
    CAPE CANAVERAL, Fla. - SpaceX is closer to understanding last month's rocket explosion at its launch pad. The company already had targeted the rocket's helium system as being breached. On Friday, SpaceX said the investigation has been further narrowed to one of the pressurized helium containers, located in the second-stage oxygen tank. Source
  • Did Microsoft out-Apple Apple? Surface computers take aim at Macbook domain

    Tech & Science CBC News
    Is Microsoft the cool kid of computers again? Technology analysts and fans couldn't help but compare this week's press events from the headquarters of both Apple and Microsoft, who — in an unusual move — unveiled major new hardware at events one day apart. Source
  • 'We have our pot of gold': Spacecraft sends back last bit of data from 2015 Pluto flyby

    Tech & Science CTV News
    CAPE CANAVERAL, Fla. -- NASA's New Horizons spacecraft has sent back the last bit of data from its 2015 flyby of Pluto. The picture -- one of a sequence of shots of Pluto and its big moon, Charon -- arrived earlier this week at Mission Control in Maryland. Source
  • 'We have our pot of gold': Spacecraft returns last data from 2015 Pluto flyby

    Tech & Science CTV News
    CAPE CANAVERAL, Fla. -- NASA's New Horizons spacecraft has sent back the last bit of data from its 2015 flyby of Pluto. The picture -- one of a sequence of shots of Pluto and its big moon, Charon -- arrived earlier this week at Mission Control in Maryland. Source
  • Users mourn Vine as Twitter scraps quirky, beloved app

    Tech & Science CTV News
    NEW YORK -- You can watch any video for six seconds, played on an infinite loop. The funniest ones only get more ridiculous with repetition. That was the beauty of Vine, the simple, pioneering mobile video app that Twitter has decided to kill off. Source
  • NASA spots 'pumpkin' stars and the 'ghostly' heart of a supernova

    Tech & Science CBC News
    Just in time for Halloween, NASA has released detailed images of some of its spookier recent space discoveries — including a patch of pumpkin-shaped stars and the still-beating heart of a supernova. The space agency's Kepler and Swift missions have discovered a group of spinning stars that produce X-rays at more than 100 times the peak levels ever seen from the sun. Source
  • Weeks after recalling bars, Soylent halts production of powder mix

    Tech & Science CBC News
    Weeks after recalling meal replacement bars that made some customers sick, Soylent has now halted production of its powder drink mix over similar reports. The U.S.-based company says it discovered the problem with its Powder 1.6 meal replacement while investigating why its Soylent Bars made some customers violently ill. Source
  • Iceland is poised to elect a party of hackers and internet-freedom activists

    Tech & Science CBC News
    The past few years have been stormy for Iceland, a country threatened by volcanoes and brought low by bankers. Now, Icelanders are thinking of putting their trust in pirates. Polls suggest the party — formed in 2012 by a group of anarchists, hackers and internet-freedom activists — is supported by as many as one in five voters and could emerge from Saturday's parliamentary election at the head of a new government. Source
  • LIVE blog: Tech companies show off innovations in Toronto

    Tech & Science CTV News
    Many Canadians dream of being a successful entrepreneur, inventor, and even the next Bill Gates, Steve Jobs or Mark Zuckerberg. Today, many of those innovative Canadians are convening in Toronto for a one-day summit hosted by Google called Go North. Source