By T.J. Pignataro
On one recent research trip down the Mississippi River, biologist Avril Harder watched as an Asian carp rocketed out of the water and broke her boss’s nose.
There was no such adventure Friday in Buffalo Harbor, but it was the kind of experience Harder and two other Midwest scientists were working to prevent in the Great Lakes and other upstate waterways.
The three-member research team from Central Michigan University collected 50 two-liter water samples from the surface and the bottom of Buffalo’s outer harbor last week. They were searching for “environmental DNA” – the basis of a rapidly-developing forensics technology – to determine what non-native creatures have invaded local waters.
Think “CSI: Great Lakes.”
“It’s a lot like that,” said Andrew Tucker, the team’s leader and an invasive species specialist for the Nature Conservancy associated with Central Michigan.
Fish, invertebrates and plants constantly shed genetic material in the lakes that can be captured by collecting water samples.
Those samples are then run through very sensitive – and expensive – electronic processors at a Central Michigan laboratory, allowing scientists to find the species that are, or are not, present in our waters by identifying specific genetic markers in the collected eDNA.
“Some people have called eDNA a ‘genetic smoke alarm,’” Tucker said. “Like a smoke alarm, which alerts you to the presence of a fire, this eDNA alerts us to an aquatic invasive species.”
Environmental DNA shows some species of Asian carp already are in the Great Lakes basin.
Scientists from the U.S. Fish & Wildlife Service collected nearly 300 monitoring samples last year at the western end of Lake Erie. They found a single silver carp – the fish that’s noted for jumping out of the water – near the Cherry Street bridge in Toledo, Ohio. A few other positive hits were recorded the year before in the same area and for the silver and big head carp in 2011.
Scientists at Notre Dame and Central Michigan universities pioneered eDNA markers for Asian carp. That work led to the first identifications of the species above the electric barrier near Chicago that separates the Mississippi River and Great Lakes basins.
New tech in canal area
The trip and samples taken here last week, Tucker believes, represent the first time eDNA technology has been used in Buffalo and on the Erie Canal.
Although the technology is still relatively new, scientists are confident in its precision.
“The simplest way to explain it is, if you detect it, there’s a live fish in the water,” Tucker said. “The technology is pretty cutting-edge.”
The research team of Tucker, Harder and Ben Wegleitner is funded by the U.S. Environmental Protection Agency’s Great Lakes Restoration Initiative. They concluded their week-long jaunt across upstate New York on Saturday, collecting 50 more samples on the Erie Canal in Tonawanda.
They began last Monday on the Oswego River, spent Tuesday in the Erie Canal at the Montezuma National Wildlife Refuge and Wednesday on the Genesee River in downtown Rochester.
The scientists have identified 42 “high-risk” invasive species, including both plants and aquatic life, that are able to survive in the Great Lakes system. The system, for the purposes of their research, also includes the Champlain basin and Hudson and Mohawk River watersheds.
The Erie Canal, which has been celebrated for almost two centuries as the waterway that connected east with west, is now feared to be a possible conduit for invasives.
“The focus is the canal as the pathway,” said Wegleitner, a graduate biology student at Central Michigan.
Invasives cause harm
The research team is searching for more than just signs of the much publicized Asian carp. The waters here also are being tested for the fast-spreading and waterway choking hydrilla plant; the aggressive, plankton-consuming “killer shrimp” invertebrate; the predatory northern snakehead fish; the Eurasian ruffe and the Asian clam.
“Buffalo is one of the largest ballast water discharge points in the Great Lakes,” Tucker said. “We’re here to get an understanding or a sense of the threat level the Erie Canal poses as a pathway for aquatic invasive species.”
The hydrilla plant is already here. The rapidly-growing plant, native to Asia, is in Tonawanda Creek and the Erie Canal not far from the Niagara River. Not only does it aggressively overtake native plant life, but it creates poor habitat for aquatic life, clogs water plant intakes and imperils boating and fishing.
It’s one of the reasons state legislators approved a new law this year that requires boaters to clean, drain and dry their boats before launching or leaving a public boat launch.
Some of other “higher priority” invasive fish species besides the Asian Carp are also considered a threat to native fish populations and the local aquatic ecosystem.
The northern snakeheads are an Asian native that, unlike the carp, are “aggressive predators” with big teeth that eat other fish, Tucker said. A popular food fish in the Asian community, they’ve been detected downstate, including in Catlin Creek in Orange County.
The fear is that there is “some potential they could travel up the Hudson River to the canal and up this way,” Tucker said.
And the irony wasn’t lost on Tucker that on a day when local anglers were fishing around the Buffalo Harbor for a combination of bass and walleye in an annual fundraising tournament, he and the other researchers were also hunting for signs of the invasive Eurasian ruffe, which studies have suggested could reduce walleye populations between 10 and 20 percent if they get into lake waters.
“They could compete with the yellow perch or walleye,” said Tucker. “They’re not a popular sport fish. They’re not as big. It’s kind of a slimy little fish.”
Aquatic invasive species annually cost the Great Lakes region $100 million in their impact on commercial and recreational fishing, tourism and damage to water treatment plants and power facilities, according to economic studies. And that does not include the ecological and environmental ramifications.
Early detection is vital
The three-member research team – aboard “Wendt Fishing,” a 17-foot fiberglass skiff provided to the Nature Conservancy by the Wendt Foundation – began its sampling inside the Small Boat Harbor before moving both north and south through the coves and slips around the outer harbor.
At each sampling point, Harder logged in the exact GPS coordinates, depth, water temperature and other notes.
Tucker, wearing protective gloves, leaned over the side of the boat to gather the water sample.
“He’s scooping the surface of the water,” explained Wegleitner, who steered the craft. “We’re looking for samples on the surface.”
DNA survives on the surface of the water for between 24 hours and a week depending on conditions, Tucker said. That’s why scientists can be so precise with their projections about where the fish are.
“If we were to detect something here, it would be virtually impossible it would be coming from far away,” he said.
The samples collected here will be filtered, then the process of isolating and extracting the eDNA will be completed in Michigan. Scientists identify the species any eDNA belongs to by comparing the genetic markers against an already vast library of pre-logged data.
It could be up to six months or so before results taken from Buffalo Harbor are processed.
If something is found, the state Department of Environmental Conservation will be advised of the discovery. The agency and other stakeholders would then likely pursue response actions, which would likely include additional – and more detailed – testing followed by measures to control the spread of the invading organisms.
“You want to stop then before they come in,” said Tucker, “but if you can’t, then in invasive species work, early detection is the gold standard.”