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.



Advertisements

Latest Tech & Science News

  • Driverless hover-taxi makes first 'concept' flight in Dubai

    Tech & Science CTV News
    Dubai has edged closer to its goal of launching a pioneering hover-taxi service, with the authorities announcing a successful "concept" flight was made on Monday without passengers. Safety features for the two-seater air taxi include emergency parachutes and nine independent battery systems, according to Dubai's Road and Transport Authority (RTA). Source
  • 'Fatberg' found in Baltimore sewer system after overflow

    Tech & Science CTV News
    BALTIMORE -- A massive "fatberg" made up of congealed fat, wet wipes and other waste has been named as the culprit in a sewer overflow in Baltimore. The overflow discharged about 1.2 million gallons of sewage into the Jones Fall stream last week. Source
  • Multiple challenges remain to Fukushima nuclear cleanup

    Tech & Science CTV News
    TOKYO -- Japan's government approved a revised road map Tuesday to clean up the radioactive mess left at the Fukushima nuclear power plant after it was damaged beyond repair by an earthquake and tsunami in 2011. Source
  • 'Critter shelf' project aims to help wildlife cross NY roads

    Tech & Science CTV News
    BOONVILLE, N.Y. -- The New York state Department of Transportation and The Nature Conservancy are testing a new "critter shelf" installed in a highway culvert to help wildlife cross safely. The structure was installed this summer inside a 138-foot-long, 14-foot-tall culvert south of Boonville, in central New York. Source
  • Japan's Fukushima cleanup plan delays removal of fuel rods

    Tech & Science CTV News
    TOKYO -- Japan's government on Tuesday approved a revision of its 30-to-40-year plan to decommission the Fukushima nuclear plant, delaying by three more years the removal of radioactive fuel rods stored at two of the three reactors damaged in the 2011 disaster. Source
  • WhatsApp service disrupted in China as censorship tightens

    Tech & Science CTV News
    BEIJING -- The encrypted messaging service WhatsApp suffered intermittent disruptions in China on Tuesday as communist authorities tightened censorship ahead of a major ruling party meeting. Attempts to set up new WhatsApp accounts on some cellphones were met with network error messages. Source
  • Russia threatens to block Facebook next year

    Tech & Science CTV News
    MOSCOW -- Russia's communications watchdog has threatened to block the access to Facebook next year if the company does not store its data locally. Alexander Zharov, chief of the Federal Communications Agency, told Russian news agencies on Tuesday that they will work to "make Facebook comply with the law" on personal data, which obliges foreign companies to store it in Russia. Source
  • Russia threatens to block Facebook over data storage

    Tech & Science CTV News
    MOSCOW -- In its latest attempt to wrest control of the Internet, Russia's communications agency on Tuesday threatened to block access to Facebook if the company refuses to store its data locally. Alexander Zharov, chief of the Federal Communications Agency, told Russian news agencies on Tuesday that they will work to "make Facebook comply with the law" on personal data, which obliges foreign companies to store it in Russia. Source
  • Twitter explains why Trump North Korea tweet wasn't removed

    Tech & Science CTV News
    WASHINGTON -- Twitter is citing "newsworthiness" and the public interest as reasons why it didn't remove U.S. President Donald Trump's declaration in a tweet that North Korean leaders may not "be around much longer." Trump tweeted Saturday: "Just heard Foreign Minister of North Korea speak at U.N. Source
  • Uber to announce it's leaving Quebec due to stricter government rules

    Tech & Science CBC News
    Just days after the company warned it may leave the province, Radio-Canada has confirmed Uber will cease operations in Quebec. Last week, an Uber statement said "new and challenging" provincial regulations "significantly threaten" the company's ability to continue operating. Source