An Asian carp was pulled from the Scajaquada Creek where it flows into the Black Rock Channel. Now, take a moment and catch your breath. This occurred May 17, 2007.

It appears to be the only documented Asian carp plucked from Buffalo Niagara’s waterways.

And it’s likely that the fish had been previously sterilized by man and dropped into the waters to help control underwater plant growth, according to a SUNY Buffalo State scientist whose late colleague snagged the fish.

There’s no indication the now-notorious invasive fish has gained any sort of a foothold either here or in the rest of Lake Erie, where three Asian carp also were captured by commercial fishermen as early as 1995.

Still, you’ve probably seen the video. Hundreds of the fish, spooked by a passing boat motor, catapult themselves en masse above the surface of the water. That variety is but one of four main species of Asian carp – the silver carp.

One of the others – the grass carp – was the type found in Scajaquada Creek. Those three other carp – discovered in 1995 and 2000 near Sandusky, Ohio, and just due north of there on the Canadian side of the lake, also in 2000 – are of the “Bighead” carp species. Those can weigh 80 to 100 pounds and live more than two decades.

It’s a threat that’s chilling to Jim Hanley, a well-known local fishing charter captain who docks in Buffalo.

“Lake Erie is the greatest fishing lake in the world,” Hanley said. “To see anything happen to it would be devastating.”

Of course, Asian carp are not the only invasive species threatening Lake Erie and the other Great Lakes. Scientists are tracking more than 180 different species of invaders – including the spiny water flea, round goby and those pesky zebra and quagga mussels – in Lake Erie. Some, like the zebra and quagga mussels, have exploded in numbers and have had greater impacts lakewide. But non-native species are, in one way or another, affecting Lake Erie’s ecosystem whether through water quality, disruptions to the food web, lake commerce or other issues.

“It affects the whole system,” said Alexander Y. Karatayev, director of the Great Lakes Center at Buffalo State.

While scientists from Toledo to Buffalo are studying and managing invaders already here, others are strategizing ways to thwart the arrival of additional species like the golden mussel, killer shrimp and the anxiety-provoking Asian carp.

“Too often we wait for things to happen and it costs way more to deal with it afterwards,” Jonathan M. Bossenbroek, an associate professor of ecology at the University of Toledo’s Lake Erie Center, said about the introduction and spread of invasive species. “It’s hard to get undone when it happens.”

Asian carp

Given the havoc that Asian carp have wreaked on the Mississippi River in recent years after getting into the water through flooded Arkansas ponds where they were stocked to control weeds, fears abound that a similar catastrophe could beset one or all of the Great Lakes if the fish is introduced or migrates.

All that stands in the carp’s way is an electrical barrier that separates carp populations in the Chicago Sanitary and Ship Canal from Lake Michigan. For now, the U.S. Army Corps of Engineers-managed barrier, which is about 25 miles west of downtown Chicago, appears to be working.

Then again, there could be other means of transmission of Asian carp to the lakes – natural and man-made.

The Army Corps has identified 18 potential pathways connecting the Mississippi River basin with the Great Lakes’ watershed in the event of flood. Most are low-to-medium risk, but at least one – the Eagle Marsh wetland preserve near Fort Wayne, Ind. – has a high risk. And that offers a possible entry for the carp into a tributary of Lake Erie.

“Every time there’s a potential connection there, there’s a possibility for the fish to get through,” said Jack Drolet, program manager at U.S. Army Corps of Engineers Cincinnati office. The Army Corps, he said, is raising the berms there.

And if the fish don’t get here that way, they may be introduced by man.

A black market for live Asian carp exists in Chinatown fish markets in Canada. The trade is lucrative enough for some truckers to chance illegally smuggling tens of thousands of the fish at a time across the border in semi-trucks disguised as water tankers.

“The fish are more valuable alive,” Drolet said.

Every year, Drolet said, border agents nab three or four truckers with a cargo of upwards of 50,000 Asian carp that were raised on farms in the southern United States, Drolet said. By accident or some other means, there’s a threat of massive release to the lakes.

However it happens, if enough of this invasive fish were able to get into Lake Erie and multiply, the balance of the lake’s ecosystem – not to mention a billion-dollar annual sport-fishing industry – would be at risk.

“I’m reasonably comfortable in saying we’d see undesirable effects on yellow perch and walleye,” Duane Chapman, a Missouri-based U.S. Geological Survey research fisheries biologist, said of two of the lake’s most popular fish. “They could be really severely hurt – large reductions in population – probably not extinction though.”

It’s nothing North Tonawanda fisherman Rich Davenport hopes to experience.

“They eat massive, massive volumes of plankton, and what they do is collapse the food chain from the bottom up,” Davenport said. “If you lose minnows, you lose game fish. If you lose game fish, you lose your whole industry.”

“You don’t know there’s a problem with an invasive species until it explodes.”

Charter captain Hanley agrees.

That’s why he said more should have been done a long time ago to deal with the threat.

Moreover, the recent scientific discovery of the carp’s DNA in the lake is enough to prove they’re already here, he insists.

Hanley expects Asian carp will start showing up in Lake Erie within the next couple of years.

“The barn door has been closed after the horses are out,” Hanley said about the safeguards now in place in Chicago. “I know they’re already in the lake. We haven’t seen them yet but they’re here.

“You don’t see the mice in your house until they start eating your food.”

Threat debated

If Asian carp were able to invade Lake Erie and multiply, scientists as well as fishermen like Davenport fear that they’d consume such a large amount of the nutrition that existing fish and aquatic animals that rely upon the same food chain would be severely affected.

Chapman, who co-wrote a study published last year on the topic in the Journal of Great Lakes Research, is “confident” Asian carp could reproduce in Lake Erie, establish populations and possibly overtake the lake. But, then again, he said, neither is it a certainty.

There are just a lot of unknown variables, he said.

“It’s one of those things you don’t want to try and find out,” he said. “Anytime you have a big change like this, you’re going to have winners and losers. If you want to have walleye and yellow perch, this is probably nothing you want to see happen.”

Meanwhile, Amy J. Benson, a fisheries biologist in Gainesville, Fla., is less bullish on the Asian carp’s chance to take over the lake because of the its unusual spawning preferences as well as water temperature, flow and other variables.

“It doesn’t mean it can’t happen,” said Benson, who reported in recent weeks on the Asian carp’s distribution across the continent. “I don’t want to paint a disaster, but I also don’t want to be too cautious and say ‘nothing’s going to happen.’ ”

Don Zelazny, the state Department of Environmental Conservation’s Great Lakes program coordinator, agrees with Benson.

“The jury is still out ... in terms of what degree Asian carp could expand into Lake Erie,” said Zelazny, citing the silver and bighead carps’ preference for spawning in “fast-moving water” – something that Lake Erie does not have.

Still, Zelazny cautioned, “there are some real horror stories involving Asian carp.”

As of now, the Asian carp remains only a threat.

Mussel invasion

One invasion that has occurred and is noticeable is the mussel invasion, zebra and quagga.

And their presence may have had the biggest impact on Lake Erie in recent years. At first glance, you might say their effect has been beneficial. But looks can be deceiving.

“The water became clear,” said Karatayev, the Buffalo State professor who specializes in the study of mussels. “But there’s less food in the water column.”

Less food means fewer fish.

First discovered in the lake in 1986, the zebra mussel may have been brought to North America while still in its larvae stage in ballast water aboard a vessel from the then-Soviet Union just a few years earlier. Scientists’ theories are based on the fact that the Ukrainian port where the ship got its water was the only one in the world where both zebra and quagga mussels were then known to exist.

Quagga mussels were found in Lake Erie in 1989 and now account for about 98 percent of the mussels in our eastern basin, Karatayev said.

He describes the little critters as “the most aggressive invaders in the Northern Hemisphere.”

Populations of both appear to be tailing off slightly now, possibly because there’s less food for them. However, they are still ubiquitous.

“There are still a lot of them,” said Karatayev, “but not as many as six, seven or eight years ago.”

And don’t let the mussel fool you. Clearer lake water doesn’t necessarily mean cleaner lake water.

The mussels, besides stealing oodles of those nutrients coveted by other indigenous lake animals, filter pollutants from the water but then “spit them out,” depositing them in the top-layer sediment at the lake’s bottom, robbing the pollutants of an opportunity to easily pass through the water’s current and out of the lake altogether.

“They don’t like it,” said Helen Domske of New York Sea Grant. “Mussels spit it out like babies spit out peas.”

Added Zelazny: “What the mussels are essentially doing is transferring the contamination into the sediment.”

Round gobies

Then there’s the round goby fish.

The aggressive species fights with native fish populations for both food and territory. It was discovered in the lake around 1990.

Not only can they feed during the dark, unlike many native species, but they spawn more often and guard their eggs, according to Sea Grant, a nationwide network – administered through the National Oceanic and Atmospheric Administration – of 32 university-based programs that work with coastal communities.

The goby, which can feed on mussels, is also believed to have spread toxins from them “up the food chain,” where they are eaten by larger fish. Some also suspect the goby played a role in the large avian botulism outbreak on the lake about 10 years ago.

“The bacteria itself is in the ecosystem,” Domske said. “The quagga mussels pick it up. The round gobies eat them, some get incapacitated by the toxin and can’t swim away.”

That makes them easy pickings for a passing loon. The bird swoops down for a toxic goby fish dinner. Two is enough to kill one bird.

Spiny water flea

Yet another invasive species to explode in the Great Lakes in the last few decades is the spiny water flea.

Also believed to have arrived from the ballast water of ships originating around the Black Sea in the 1980s, this water flea, which feeds on zooplankton, is blamed for adding to the disruption of the lake’s food chain, scientists say. Zooplankton are those floating microscopic organisms comprising the base for the lake’s food chain.

Again, less floating food to eat means fewer small fish. Fewer small fish to eat means fewer medium-size fish. Fewer medium-size fish to eat means fewer big fish. And fewer big fish?

Well, who wants to go out fishing all day only to return home with an empty bucket?

You get the picture.

Stemming the tide

Unlike some of the other issues facing the lake, the one of invasive species seems to be the hardest to predict and most difficult to manage. One can regulate the frequency and amount of wastewater discharge. Reduce phosphorus run-off by changing agricultural practices. Stop beach littering by changing attitudes.

Stemming the tide of invasive species is a tougher nut to crack.

Their numbers in Lake Erie is a figure that seems to be ever-rising with canals, waterways and shipping vessels connecting the Great Lakes with the outside world. There is a steep price for all that interconnectivity.

“Every time we have a new invasive species,” the DEC’s Zelazny said, “it takes up to 15 years to understand what the impact the invasive species is having on the habitat of the lake.”

Once these invaders establish colonies where they don’t belong, they are harder to get rid of than cockroaches.

“I’m not aware of one invasive species that has gotten into Lake Erie that has been controlled or eliminated,” Zelazny added. “Once they’re there, they are very hard to control and almost impossible to eradicate.”