оказывается, их "историческая родина" - каспийское море. но совсем недавно (по разным источникам - от 1985 до начала 90-х) эти штуковины попали в великие озёра, в штатах. да ка-а-ак там разрослись!
сейчас очистка только одних днищ судов и водозаборных труб обходится в десятки миллионов долларов. а сколько они там пока ешё не хватились чистить?!
кстати, статья была не про них даже, а про новую напасть - азиатских карпов. которые если прорвутся в великие озёра (пока их какая-то электрическая засада держит), то вообще всё там пожрут и уничтожат один из главных источников питьевой воды америки.
для истории - вот вся заметка -
Great Lakes beware, the Asian carp are here
Chicago has battled fire and flood since its founding in 1837. A more dangerous menace now looms: an invasion of alien fish.
The Asian carp, a species hitherto unknown in the Great Lakes, has found its way from fish farms in the southern state of Arkansas and is threatening to enter Lake Michigan.
Local conservationists and politicians fear disaster. They say that the fish, which can grow to four feet and can weigh 100 pounds, could seriously deplete native stocks of salmon and whitefish and become the dominant species in all five Great Lakes. The fish is a voracious eater, feeding on animal and plant plankton that is the staple food for the young native fish in the lakes.
"Based on the havoc these carp have wreaked on the Mississippi river, we have every reason to believe they would devastate the Great Lakes ecosystem as well, should they enter the lakes," says Gerry Barnhart, chairman of the Great Lakes Fishery Commission, founded 50 years ago by the US and Canada to combat "invasive species".
The prospect has resonance beyond Chicago: the Great Lakes are the largest surface freshwater system on earth, containing more than 90 per cent of the surface fresh water in the US.
The Great Lakes Commission, another US-Canadian body involved in the management and protection of the lakes, says that as many as 160 non-indigenous aquatic species have invaded the Great Lakes from around the world.
вот кусочек про зебровых мидий:
Many, like the zebra mussel that first appeared in the early 1990s, were carried to North America in ballast water by ships sailing from the Caspian Sea. Zebra mussels have spread across the Great Lakes, clogging industrial water intakes, encrusting the keels of boats and costing millions of dollars of damage to business.
The Asian carp was originally introduced into the US from Asia in the early 1970s to control algae growth in aquaculture ponds. The fish, capable of covering 40 miles in a year, have made it to within 20 miles of Chicago along a canal fed by Lake Michigan.
The only thing standing between the fish and Lake Michigan is an electrified barrier built in 2002 whose electrodes are expected to wear out within eight months.
Last Monday the US army corps of engineers broke ground on the first stage of a two-stage project to build a second barrier, funded by the US army and the state of Illinois.
But there is a $1.8m (€1.6m, £1m) funding shortfall and the second stage is under threat. Officials say it is only six months before the carp reach the barrier.
Phil Moy, a specialist in non-indigenous species at the University of Wisconsin and chairman of the barrier project, says the carp are a threat even to humans. "These are large fish and not very pretty," he says. "They respond to the sound of boat motors and can leap six feet out of the water and collide with people. We really have to stop them."
плывёшь себе на лодке, а из воды - бац, карп! и сшибает тебя в воду! я как-то писал уже про месть карпов...
Officials at a conference yesterday in Chicago organised by the International Association of Great Lakes and St Lawrence Mayors appealed for legislation to help combat the threat.
But with dozens of national and local agencies responsible for Great Lakes policy, there is a fear that bureaucratic gridlock means funding will come too late, if it comes at all, for the Chicago barrier.
"These things are coming up the canal. They're not worried about federal or state or local governments," says Richard Daley, Chicago's mayor. "If we don't stop them now, they will destroy the Great Lakes."