Something unnatural and menacing that overwhelmed the waters of Scotland’s Loch Lomond in the 1980s is moving into the Great Lakes.
A fish never before seen in the British Isles, the European river ruffe was accidentally introduced into the famous Scottish lake 20 years ago. With no predators to keep its numbers down, by 1983 the ruffe made up 90 percent of Loch Lomond’s fish population.
In 1986 the same fish was first found in American waters in Duluth Harbor on the far western end of Lake Superior. Now the ruffe (pronounced “rough”) makes up 65 percent of the harbor’s fish population. And it is spreading quickly eastward toward the rest of the Great Lakes, establishing colonies along the shoreline as it drives out native fish.
Author Michael Crichton has made millions with fictional accounts (“Jurassic Park” and “The Andromeda Strain”) that tell of alien species raising havoc after being introduced to new environments.
In real life, introduced species, known to biologists as “exotics” or “non-indigenous species,” often do raise havoc, causing billions of dollars in economic and ecological damage.
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The sea lamprey invaded the Great Lakes in the 1940, followed in the 1960s by the massive onslaught of the alewife.
But the biggest assault ever on the Great Lakes ecosystem began less than 10 years ago when three alien species began colonizing the lakes. One, the zebra mussel, already is well-known. The other two, the ruffe and the round goby (pronounced GO-bee) soon will be.
Federal officials now are so concerned about the ruffe that early in January they will hold three public hearings on plans to stop the fish from reaching the other Great Lakes.
The U.S. Fish and Wildlife Service will hold one of the hearings at 7 p.m. Tuesday at the Maine North Facility, a state office at 9511 Harrison St. in Des Plaines.
The Ruffe Control Program is sort of an 11th-hour attempt to contain the fish in Lake Superior’s western end, thus staving off projections of $7 billion in damage to Great Lakes fisheries. Central to the program being considered are plans next spring to poison the ruffe as they mass in river spawning grounds.
U.S. and Canadian officials want to use the same poison (3-trifluoromethyl-4-nitrophnol) they have been using for decades to control sea lampreys. The lamprey devastated native fish populations in the Great Lakes before it was brought under control in the 1960s.
The ruffe sneaked through the same unguarded back door that the zebra mussel and goby used to get here from Europe.
All three aliens came in the ballast water of empty oceangoing ships arriving from Europe in the mid-1980s to take on grain bound for the former Soviet Union.
What probably allowed them to survive the journey and thrive once they were pumped off into the waters of the American ports was a successful, well-intentioned Great Lakes cleanup campaign.
Environmentalists waged the campaign in the 1960s and 1970s. In part, they lobbied for regulations that stopped oceangoing freighters, known as “salties” to Great Lakes mariners, from dumping their filthy ballast water into the Great Lakes.
Since the early 1980s, the salties have carried in and jettisoned only clean water from their ballast tanks while in the lake system.
What nobody knew or could have foreseen is that the foul, polluted ballast water had one positive effect. It was so foul, it killed all living things accidentally caught as the ballast water was taken aboard in foreign ports.
With clean ballast water, the ships have, in effect, become trans-oceanic freshwater “corridors” that have floated alien creatures from foreign freshwater ports across salty seas to the Great Lakes.
The zebra mussels and goby came from the Black Sea area of Europe. The ruffe probably came from more northerly European ports. All three are taking hold here in waters that contain none of their natural enemies. The zebra mussel and goby already are causing problems along the Chicago shoreline.
“Pretty soon we’re going to have to have a lobby working to pollute the harbors again,” joked John Janssen, a Loyola University Chicago biology professor.
Janssen is one of North America’s ranking authorities on the goby and studies how nature uses human technology and laws to nudge migrations of lifeforms into areas nobody wants them to go.
Of the three recent alien arrivals, the bug-eyed goby was the last to be discovered in the Great Lakes. It was first noticed in 1990 near Detroit. Since then, the goby, which grow to about 8 inches long, have begun swarming in large numbers both there and in the Calumet Harbor.
It is giving Lake Michigan fishermen fits by apparently driving away the most delicious and beloved sport fish in the lake, the yellow perch.
“We have no idea yet how serious its impact will be, but now that it’s here, there is no way to get rid of it,” said Janssen. “Basically, it’s like cockroaches, you have to learn to live with them.”
One of the dangers of such transplantations is that no native animals recognize the newcomers like the goby as a possible entree on the dinner menu. So the newcomers get a free ride on the food chain, eating what they want without getting eaten. That causes an exponential population explosion among the unhunted aliens.
By eating the native species or competing with them for the same living space and food sources, exotics can decimate the natives or drive them into outright extinction. Wherever there is a successful exotic transplant, the ecosystem must find a new equilibrium, changing it forever, usually leaving it less healthy than it was.
The goby, Janssen said, occupies lake and river areas with rocky bottoms. He said it will probably spread easily up both sides of Lake Michigan, settling in rocky waterfronts such as those at Chicago, Waukegan, Milwaukee and Green Bay.
If the goby wasn’t bad enough, the ruffe seems a likely bet to soon become a full-blown disaster in Lake Michigan, too.
Small and bony, the 3- to 5-inch ruffe is virtually inedible, disliked even by larger predator fish.
Each year it has been moving inexorably closer to St. Mary’s River on the eastern end of Lake Superior. If it reaches there, it will rapidly spill into Lake Huron and the rest of the Great Lakes, where it will find warmer, shallower waters even more hospitable, especially in Lakes Erie and Michigan.
“It’s those places I expect it to become a serious pest,” said Jim Selgeby, a federal biologist with the National Biological Survey in Ashland, Wis. “Once it’s in Lake Michigan, (the ruffe) will occupy all of Green Bay and all of the southern part of the lake.
“We think if we look across the next century, they pose a problem for all of North America. They can occupy practically the entire U.S. and Canada.”
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The third threatening newcomer, the zebra mussel, is already well on its way to such a widespread occupation.
First identified in the Great Lakes in 1986, current estimates see the tiny mollusk doing at least $3 billion worth of damage in the next few years. It encrusts everything from navigational buoys (sinking them in the process) to water-intake valves (clogging them up so as to be unusable).
The mussels so thoroughly devour plankton that wherever they go, they rob the water of primary nutrients. They have caused local extinctions of native fish populations in Lake St. Claire in Michigan. They have virtually ruined Lake Oneida in New York, coating its surface with green, paintlike scum of rotted, fetid seaweed.
Now the mussels are migrating with astonishing speed through the rivers of the nation’s heartland.
Two summers ago a few zebra mussels were discovered in the Ohio River as it passes southern Illinois. This summer there were 4,000 to 8,000 mussels occupying each square yard of the river bottom in the same location.
The ballast water “corridor” that the three aliens used to get here now is shut down.
The zebra mussel’s early adaptation and rapid expansion in the Great Lakes alerted scientists to something going wrong.
As a result, since 1989, most ships voluntarily began replacing freshwater ballast at sea with salt water before arriving in North America. Since 1993 they have been required to do so by law.
But it was an act akin to closing the barn doors long after the horses ran away. The mussels, gobies and ruffe already are here to stay, poised to wreak havoc.