Giant carp threat to Great Lakes

A A A

For at least the past decade they have been moving upstream at the rate of 50 miles a year. Now they are no more than 25 miles away from wrecking the ecosystem of North America's largest water system.

Fisheries experts in Chicago are battling to keep thousands of huge Asian carp from entering Lake Michigan and the rest of the Great Lakes. The fat, voracious fish that escaped into the Mississippi River from ponds hundreds of miles away are now within the city limits.

"They could wipe out the base of the food chain in the entire Great Lakes," said Dennis Schornack, US chairman of the International Joint Commission, which oversees the water systems affecting the US and Canada. "We could end up with a situation where the Great Lakes are nothing more than a carp pond."

The carp, native to the Far East, were introduced in Arkansas in the early 1970s to act as algae eaters by the catfish-farming industry. But many escaped as a result of floods, entering tributaries of the Mississippi and heading north in search of cooler water.

By the time the carp reach maturity they can be more than five feet long and weigh 110lb.Their size and appetite mean they are not only a threat to the food system – but also a physical threat to people. There are numerous stories of fishermen being struck by the leaping fish. One suffered a broken nose.

If man had not tinkered with the river system, the carp would not be threatening the Great Lakes. The Chicago river, which runs through the city, never had any link with the Mississippi and flowed in the opposite direction, into Lake Michigan.

But in the 19th century the river was used as a dumping ground for sewage and slaughterhouse waste and concern grew that Lake Michigan, which provided the city's water, would be polluted. So engineers built a series of canals linking the river with the Illinois River, which flows into the Mississippi basin, and reversed the Chicago River's flow.

Experts are resorting to radical methods to try to prevent the fish from entering the lake. Since April, the Army engineers have been using an electrical current to try to deter the fish.

"It is highly unlikely that it would be able to remove them from the Mississippi basin," said Mr Schornack. "That is the problem with foreign species. Once they are established it is very hard to get rid of them."

News
Pro-Russia rebels guard a train containing the bodies of victims of the Malaysia Airlines flight MH 17 crash in Torez, Ukraine
i100
Life and Style
Child's play: letting young people roam outdoors directly contradicts the current climate
lifeHow much independence should children have?
Arts and Entertainment
Tycoons' text: Warren Buffett and Bill Gates both cite John Brookes' 'Business Adventures' as their favourite book
booksFind out why America's richest men are reading John Brookes
Arts and Entertainment
<p><strong>2008</strong></p>
<p>Troubled actor Robert Downey Jr cements his comeback from drug problems by bagging the lead role in Iron Man. Two further films follow</p>
filmRobert Downey Jr named Hollywood's highest paid actor for second year running
PROMOTED VIDEO
Have you tried new the Independent Digital Edition apps?
Property
Sign here, please: Magna Carta Island
propertyYours for a cool £4m
News
people
News
The Commonwealth flag flies outside Westminster Abbey in central London
news
Arts and Entertainment
Struggling actors who scrape a living working in repertory theatres should get paid a 'living wage', Sir Ian McKellen has claimed
theatre
News
Skye McCole Bartusiak's mother said she didn't use drink or drugs
peopleActress was known for role in Mel Gibson film The Patriot
Arts and Entertainment
tvWebsite will allow you to watch all 522 shows on-demand
Arts and Entertainment
filmThe Rock to play DC character in superhero film
News
i100
Arts and Entertainment
Damon Albarn is starting work on a new West End musical
artsStar's 'leftfield experimental opera' is turning mainstream
Life and Style
Paul and his father
artsPaul Carter wants to play his own father in the film of his memoirs
Sport
Ben Stokes trudges off after his latest batting failure for England as Ishant Sharma celebrates one of his seven wickets
cricket
Arts and Entertainment
Members of the public are invited to submit their 'sexcapades' to Russell T Davies' new series Tofu
tv
News
Sky's Colin Brazier rummages through an MH17 victim's belongings live on air
i100
Arts and Entertainment
Keira Knightley and Benedict Cumberbatch star in the Alan Turing biopic The Imitation Game
arts + ents'The Imitation Game' stars Benedict Cumberbatch and Keira Knightley
Have you tried new the Independent Digital Edition apps?
iJobs Job Widget
iJobs General

Legal Cashier - Oxford

Very Competitive: Austen Lloyd: Legal Cashier - Oxford We have an excellent ...

Legal Cashier - Oxford

Very Competitive: Austen Lloyd: Legal Cashier - Oxford We have an excellent ...

Production and Merchandising Assistant

£19,000 - £21,000: Sauce Recruitment: A contemporary, original wholesale distr...

PPC Account Managers

£25k - £30k (DOE): Guru Careers: Two expert PPC Account Managers are needed to...

Day In a Page

Some are reformed drug addicts. Some are single mums. All are on benefits. But now these so-called 'scroungers’ are fighting back

The 'scroungers’ fight back

The welfare claimants battling to alter stereotypes
Amazing video shows Nasa 'flame extinguishment experiment' in action

Fireballs in space

Amazing video shows Nasa's 'flame extinguishment experiment' in action
A Bible for billionaires

A Bible for billionaires

Find out why America's richest men are reading John Brookes
Paranoid parenting is on the rise - and our children are suffering because of it

Paranoid parenting is on the rise

And our children are suffering because of it
For sale: Island where the Magna Carta was sealed

Magna Carta Island goes on sale

Yours for a cool £4m
Phone hacking scandal special report: The slide into crime at the 'News of the World'

The hacker's tale: the slide into crime at the 'News of the World'

Glenn Mulcaire was jailed for six months for intercepting phone messages. James Hanning tells his story in a new book. This is an extract
We flinch, but there are degrees of paedophilia

We flinch, but there are degrees of paedophilia

Child abusers are not all the same, yet the idea of treating them differently in relation to the severity of their crimes has somehow become controversial
The truth about conspiracy theories is that some require considering

The truth about conspiracy theories is that some require considering

For instance, did Isis kill the Israeli teenagers to trigger a war, asks Patrick Cockburn
Alistair Carmichael: 'The UK as a whole is greater than the sum of its parts'

Alistair Carmichael: 'The UK as a whole is greater than the sum of its parts'

Meet the man who doesn't want to go down in history as the country's last Scottish Secretary
Legoland Windsor's master model-makers reveal the tricks of their trade (including how to stop the kids wrecking your Eiffel Tower)

Meet the people who play with Lego for a living

They are the master builders: Lego's crack team of model-makers, who have just glued down the last of 650,000 bricks as they recreate Paris in Windsor. Susie Mesure goes behind the scenes
The 20 best days out for the summer holidays: From Spitfires to summer ferry sailings

20 best days out for the summer holidays

From summer ferry sailings in Tyne and Wear and adventure days at Bear Grylls Survival Academy to Spitfires at the Imperial War Museum Duxford and bog-snorkelling at the World Alternative Games...
Open-air theatres: If all the world is a stage, then everyone gets in on the act

All the wood’s a stage

Open-air productions are the cue for better box-office receipts, new audiences, more interesting artistic challenges – and a picnic
Rand Paul is a Republican with an eye on the world

Rupert Cornwell: A Republican with an eye on the world

Rand Paul is laying out his presidential stall by taking on his party's disastrous record on foreign policy
Self-preservation society: Pickles are moving from the side of your plate to become the star dish

Self-preservation society

Pickles are moving from the side of your plate to become the star dish
Generation gap opens a career sinkhole

Britons live ever longer, but still society persists in glorifying youth

We are living longer but considered 'past it' younger, the reshuffle suggests. There may be trouble ahead, says DJ Taylor