December 2010 – Zebra Mussels

Owasco Lake affected by foam, Asian clams, blue-green algae

AUBURN — Three recent reasons for concern about the water at the northern end of Owasco Lake are likely interrelated, the Cayuga County Water Quality Management Agency concluded Thursday.

In a nutshell: the lake appears to have a growing population of Asian clams, an invasive species.

The clams consume green algae, thereby allowing competing blue-green algae to grow out of control. The blue-green algae contributes to a rise in the levels of phosphorous and other organic materials, creating white foam on top of the water.

All three issues — the algae, the clams and the foam — have generated a lot of phone calls recently from concerned residents, Environmental Health director Eileen O’Connor said.

It’s not clear whether the clams or the blue-green algae came first, or how the clams originally got into Owasco Lake.

“It’s a correlation, but I don’t think you can prove a causation,” Robert Brower of the Institute for the Application of Geospatial Technology said.

Asian clams have been in Seneca Lake since 1999 and have appeared in the last few years in Lake George, the Champlain Canal and the Erie Canal near Utica, county environmental engineer Bruce Natale said.

“They’ve been around, but they’ve just started to move around to new places recently,” Natale said.

The clams prefer water that is warm, shallow and clear, without too many weeds. Deauville Island at the north end of Owasco Lake fits that description well, Natale said.

Asian clams are hermaphroditic, meaning that one organism can reproduce on its own at a rate of 400 eggs a day, Natale said. The calcium they produce attracts zebra mussels, another invasive species.

The clams could be eliminated if the water temperature in the lake gets below 38 degrees for a period of time during the winter, Owasco Lake inspector Jessica Miles said. Without the clams, the blue-green algae and foam might go away as well.

O’Connor stressed that the foam on the lake is not from soap or laundry detergent and is not dangerous.
“Rich bodies of water with a lot of organic material will tend to foam,” she said.

The Water Quality Management Agency is coordinating a volunteer effort to determine the extent of the clam and algae problems. No clams have been reported in other lakes in the county, and the group urged residents not to transport their boats from Owasco Lake to other lakes in order to keep the clams from spreading.

Staff writer Justin Murphy can be reached at 282-2237 or justin.murphy@lee.net. Follow him on Twitter at CitizenMurphy.

How to report problems

• To report Asian clams or foam in Owasco Lake, call Owasco Lake inspector Jessica Miles at 252-4171, extension 120.

• To report blue-green algae, call the Cayuga County Department of Environmental Health at 253-1405.

Blue-green algae can cause health problems for people and animals. People should not use algae-infested water for drinking, bathing or swimming.

Special Segment: Lake Invaders

Ron Magers

November 8, 2010 (CHICAGO) (WLS) — Researchers are sounding a warning that there is a threat to the Great Lakes that may be worse than the Asian carp.

The new threat is literally eating up the basic building blocks of life in the lakes.

“We really are seeing the collapse of one of the largest lakes, food webs, in one of the largest lakes in the world,” said Dr. Charles Kerfoot of Michigan Technological University.

Dr. Kerfoot has been surprised by what he and his team have found.

“We saw a ring of chlorophyl in southern Lake Michigan,” said Kerfoot.

That was the first surprise. Something like chlorophyl is supposed to be evenly mixed in the waters of the lake. But in the late 1990s the Michigan tech team, and numerous other researchers and agencies, used boats and mini-submarines, and sophisticated buoys and even satellite imagery, to prove that a kind of doughnut exists in southern Lake Michigan. The round swirl is a merry-go-round of phytoplankton and zooplankton, the basic building block of life in the lake. The doughnut is kicked up by winter storms and it swirls around a low spot in the lake. That was surprising enough, but there was more.

“Then came the quagga mussels. We picked them up near the end of the project in 2001,” said Dr. Kerfoot.

Think of the quagga as a cousin of the more famous zebra mussel. They probably arrived in the ballast water of foreign ships. The quagga now lives in the soft bottom of the Lake Michigan. Five years ago a one-square meter soil sample of lake bottom contained dozens of them. But more recent samples show as many as 15,000 per square meter.

Quaggas are multiplying very rapidly, and they are eating the doughnut.

“They eat all the building blocks out of that water column. They are sucking down all the particulate matter, and that includes the chlorophyl. So the primary producers are being literally sucked out of the lake down to the quagga layer,” said Dr. Kerfoot.

Starting in April of 2001 when researchers first found the quagga, they found an abundance of chlorophyl, phytoplankton and zooplankton. But by 2008, they found the doughnut had been eaten away.

Further evidence is how clear the water has become in southern Lake Michigan. Kerfoot estimates the quagga are already consuming four to seven times more of the basic food building blocks than the lake can produce. He fears the lake is losing the battle.

“There’s something wrong when you get water as clear as your bathtub water. There’s nothing living in it. What is happening is a collapse of the food chain,” said Dr. Kerfoot.

The research goes on, while Dr. Kerfoot and the Michigan tech team wonder why no one else seems to hear the alarm. He says research on how to control the Quagga is desperately needed but he doesn’t know of anyone who is doing it.

Efforts made to control population of invasive clam in California

Scientists in California’s Lake Tahoe are running a pioneering marine invasive species control experiment on the Asian clam. They anticipate the results in about a month.

Certified divers and research scientists from the University of California, Davis, Tahoe Environmental Research Centre (TERC) Marion Wittmann and Brant Allen recently dove to remove two separate 100-ft by 10-ft black bottom barriers the bottom of the lake installed in July to gauge how effectively they can kill the invasive Asian clams, reports Matthew Renda for North Lake Tahoe Bonanza.

Researchers installing Bottom barrier deployment
to control Asian clam populations in Lake Tahoe. (TERC, UC Davis)

“Going by visual inspection, there were dead clams, so the barriers did have an effect,” Wittmann said. “However, workers (at the University of Nevada, Reno) are currently processing the samples, and until we get the results, we can’t truly know if the experiment was a success.”

Wittmann and Allen used a device called PONAR to collect sediment samples from lake bottoms for lab analysis.

“A lot of the animals are too small to see with the naked eye,” Wittmann said. “Also, many of the Asian clams and other native species are buried in the sediment, so the samples may contain live animals.”

The Asian clam was first seen in Lake Tahoe in 2002, and is found in waters in 38 US states. Originally a species of freshwater, it has also gone to the brackish San Francisco Bay; scientists blame the moves on the species’ significant powers of adaptation.

The clam expels high levels of nitrogen and phosphorus which provoke algal blooms. The clams also deprive native species of key nutrients and food sources by filtering high volumes of water.

Scientific studies, moreover, predict that the clams’ production of high levels of calcium could provide a hospitable environment for the introduction of quagga and zebra mussels – highly hazardous invasive species, as they could devastate the economy and ecosystem of water bodies.

Studies show that zebra and quagga mussels could survive in Tahoe, if perhaps not reproduce; the presence of Asian clams would facilitate the plague.

Back in July, Wittmann and Allen installed two large bottom barriers on separate half-ac plots on Lake Tahoe’s bottom. The 45-mm bottom barriers are thick pond liners that can deprive organisms of dissolved oxygen which they need to survive.

Lake Tahoe Species Introduction Timeline. (Graph: TERC, UC Davis)

“The goal of this experiment is to determine whether it is feasible to control clams using impermeable bottom barriers,” declared Geoffrey Schladow, director of TERC.

He said that because complete elimination of the species from the lake is not probable, the experiment concentrates on possible population control.

The experiment is estimated to cost USD 648,000; although USD 1.4 million has been assigned for studies and scientific projects to control Asian clams.

By Natalia Real
editorial@fis.com
www.fis.com

Zebra mussels spotted in two lakes

Photo courtesy of the Connecticut DEP

Zebra mussels attached to a bottle. The state DEP commissioner calls the finding of zebra mussels in two Connecticut lakes “a disturbing discovery.” The invasive species has the potential to displace native mussels, clog power plant and industrial water intakes, and affect public drinking water distribution systems.

DEP urges boaters, fishermen to take precautions to prevent spread of invasive species

Zebra mussels, an invasive species, have been discovered in Lake Zoar and Lake Lillinonah, which are created by dams along the Housatonic River in western Connecticut, the state Department of Environmental Protection announced Friday.

This is the first report of a new infestation since zebra mussels were first discovered in Connecticut in 1998 in East and West Twin Lakes in Salisbury. Only small numbers of zebra mussels have been discovered thus far, the DEP said, and it is uncertain whether they migrated from upstream sources or arrived separately.

“This is a disturbing discovery,” said DEP Commissioner Amey Marrella. “The zebra mussels have the potential to do much damage by displacing native mussels, clogging power plant and industrial water intakes, affecting public drinking water distribution systems and disrupting aquatic ecosystems.”

She asked boaters and fishermen to redouble their efforts to take precautions against spreading zebra mussels and to contact the DEP if they see them.

The zebra mussel is a black-and-white-striped bivalve mollusk that was introduced into North American waters through the discharge of ship ballast water. Since its discovery in Lake St. Clair in Michigan and Ontario in 1988, it has spread throughout the Great Lakes, the Mississippi River system and most of New York State. Zebra mussels were first found in the Housatonic River in 2009 when they were discovered in Laurel Lake in Lee, Mass., and subsequent sampling found them in the lake’s outflow into the main body of the river.

Zebra mussels have fairly specific water chemistry requirements and are limited to waters with moderate to high calcium concentrations and pH. In Connecticut, suitable habitat for zebra mussels is mostly limited to a number of water bodies in the western part of the state.

The mussel can foul boat hulls and engine cooling water systems and clog power plant, industrial and public drinking water intakes. Six hydroelectric facilities along the Housatonic could be affected, the DEP said.

To prevent transferring invasive species, the DEP said boaters should make sure they drain all water from the boat, including bilge water, compartments where fish are stored and engine cooling systems after use, inspect their boat, trailer and equipment and remove and discard any aquatic plants and animals found. At home, boats, trailers and equipment should be rinsed with tap water and fish storage compartments cleaned with bleach solution. Unused bait should be disposed of in the trash, and fish and plants should not be transported between water bodies but released into the waters they came from.

To report sightings of zebra mussels or other aquatic nuisance species, contact the DEP’s Inland Fisheries Division at (860) 424-3474. For information on zebra mussels, visit:
www.ct.gov/dep/lib/dep/fishing/anglers_guide/anguide.pdf and www.ct.gov/dep/lib/dep/boating/boating_guide/boaterguide.pdf.
– Judy Benson

Great Lakes Threats Go Beyond Asian Carp, Invasive Expert Says

Dr. Reuben Keller calls for long-term solutions to protect the Great Lakes, and the Mississippi and Illinois rivers from future aquatic invasive species.

By Steve Kellman
Circle of Blue

Community ecologist Reuben Keller has made a career out of studying aquatic invasive species in freshwater systems like the Great Lakes, and measuring their ecological and economic costs. Now a lecturer with the University of Chicago’s Environmental Studies program, Dr. Keller outlined the threat posed by invaders like Asian carp in a presentation to attendees of an Alliance for the Great Lakes webcast Wednesday.

“This is a really unique situation for invasions into the Great Lakes,” Keller said. “It’s unique in that we can see this invasion coming, and we may have the opportunity to prevent its arrival…. Asian carp gives us this opportunity to be proactive.”

But just like the more than 180 biological invaders that came before it, he warned, “we need to assume that if [Asian carp] make it to the Great Lakes, we’ll never get rid of them.”

The subject of state lawsuits, EPA and Congressional hearings, and U.S. Supreme Court motions, the plankton-gobbling Asian carp threaten the Great Lakes’ $7 billion sportfish industry with their habit of eating the bottom out of the food chain and starving fish farther up the chain. That has led several Great Lakes states to file lawsuits seeking more aggressive carp-blocking efforts. Meanwhile, U.S. legislators are debating bills that would sever the connection between the lakes and the rivers, and a White House-appointed “carp czar” is overseeing the federal control efforts.

Overall, invasive species like Asian carp, zebra mussels, fire ants and purple loosestrife cost the U.S. economy an estimated $120 billion a year, Keller said. He added that aquatic invasive species, in particular, are the largest cause of biodiversity loss in lakes around the world.

Nearly a year after environmental DNA was discovered upstream of the electrical barriers that are supposed to keep the Asian carp out of the Great Lakes, new tests continue to find evidence that the invasive species has gotten beyond the barriers, according to Keller.

“There’s been a lot of controversy about how we should interpret these results, and I’ll give you my interpretation,” he said. “Asian carp DNA is turning up so often that it is really hard to explain how that DNA is getting there without there being populations of Asian carp that are beyond the electric barrier.”

This suggests that the barriers may not be working as intended to block the fish, Keller said, but even if they do, they still won’t block invasive invertebrate or plant species from getting into the lakes from the rivers, or the other way around.

That has already happened with zebra mussels, which were first discovered in the Great Lakes in 1988 and have since entered into the Mississippi by way of the Chicago-area waterways. Zebra mussels have now spread as far west as California and cause hundreds of millions of dollars in damage in the U.S. every year by fouling the pipes that deliver fresh water to municipal drinking water facilities and power plants.

“We should expect that for many species, the Chicago Area Waterway System is still a very viable conduit,” Keller said. “There’s still a very high likelihood of future invasions, future economic and ecological impacts.”

This is one of the reasons why the Alliance for the Great Lakes supports the permanent hydrological separation of the Great Lakes from the Mississippi River Basin, said Joel Brammeier, the organization’s president.

“Asian carp are only the latest and certainly the most graphic example,” Brammeier said. “But as Dr. Keller mentioned, we’ve already donated zebra mussels and round goby to the Mississippi River Basin, something that I don’t think the other half of the continental United States is too happy about. We can certainly count today half a dozen other invaders in either direction that could move through this system.”

He added, “No technology solution has been demonstrated to be able to provide the kind of certainty against invasion that we think the Great Lakes deserve.”

Brammeier noted that the past year has seen several promising developments in the fight to block Asian carp. In June, the Great Lakes Commission, and the Great Lakes and St. Lawrence Cities Initiative kicked off a $2 million study of hydrological separation that is expected to take 18 months to complete. The U.S. Army Corps of Engineers, which oversees the Chicago-area shipping locks that other states are suing to close, is also considering separation as a long-term option.

A bill introduced in Congress in June — the Permanent Prevention of Asian Carp Act — would require the Secretary of the Army to study the feasibility of hydrological separation. Brammeier said the Alliance for the Great Lakes would continue to push for its passage.

With the midterm elections bringing many new faces to Congress and new governors to Great Lakes states like Michigan and Ohio, the Alliance will also need to work on educating the incoming politicians on issues like invasive species, he said.

Read more about Asian carp on Circle of Blue.