Dry Weather Stifles Algae Bloom, But Scientists Say Runoff Still Threat
July 8, 2016
By: Tom Henry, Toledo Blade
July 8, 2016
GIBRALTAR ISLAND, Ohio — Although near-drought conditions since May 1 will likely suppress western Lake Erie algae this summer, scientists said the probable one-year reprieve simply underscores how strongly the region’s chronic algae problem is associated with agricultural runoff.
They said it reinforces why the government and the agricultural industry must continue to move forward with programs aimed at reducing runoff from the western Lake Erie watershed 40 percent by 2025, a goal promoted by state and federal governmental bodies.
Enlarge | Buy This Image
“We do expect there to be a bloom, but substantially smaller than past years,” according to Rick Stumpf, the federal government’s lead researcher on the annual Lake Erie algae forecasts, a developing science of its own being applied nationwide.
Mr. Stumpf, an oceanographer for the National Oceanic and Atmospheric Administration’s National Centers for Coastal Ocean Science in Maryland, was one of several speakers addressing a crowd of about 75 at Ohio State University’s Stone Laboratory on Gibraltar Island, across from Put-in-Bay.
He said this year’s forecast is based on data generated and analyzed by NOAA, Heidelberg University, North Carolina State University, the University of Michigan, and an Ann Arbor-based research firm, LimoTech.
On a scale of 1 to 10, this summer’s bloom is expected to be a 5.5.
There is a large margin of error, though, because of two things — whether the region gets more rain and whether researchers have underestimated the impact of lingering algal cells from 2015, the largest bloom on record.
Mr. Stumpf said at least a quarter to a third of residual cells from the 2015 bloom — the “carry-over” — will be responsible for the 2016 bloom.
Depending on the impact of that phenomenon, known as “internal loading,” this summer’s bloom could be worse — as high as 7 on a scale of 10 — or as low as 3 on a scale of 10, he said.
The western Lake Erie watershed’s rainfall is down 4.34 inches since May 1, said Laura Johnson, director of Heidelberg University’s National Center for Water Quality Research.
New phosphorus loading into the Maumee River, the lake’s largest tributary, is way down according to data from Heidelberg’s sampling station in Waterville, she said.
“If the weather conditions stay the way they are, this is probably going to turn into a drought,” Ms. Johnson said. “Everything is really driven by whether it rains or not.”
Lake Erie’s modern algae era began in 1995, the first heavy blooms since the 1970s.
For the last 21 years, the lake’s dominant form of algae has been microcystis, a toxin-producing algae that’s 3.5 billion years old, making it one of the oldest living things on Earth.
Microcystis has been on the rise globally the last 20 years. This summer, it is especially heavy in Florida.
Mr. Stumpf said there’s a little microcystis in Lake Erie now, but not enough to form a bloom.
Though this year’s bloom could be mild, it will likely form sooner because the region experienced a warmer-than-usual June, he said.
Tom Bridgeman, University of Toledo Lake Erie Center algae researcher, said the impact of internal loading is largely misunderstood.
He jokingly referred to it as a “phosphorus hangover.”
While research into that type of loading is still in its infancy, Mr. Bridgeman said the impact of it in future years is believed to be “mild to moderate,” depending a lot on what happens with climate change.
Another algae scientist, George Bullerjahn of Bowling Green State University, said one of the most underrated forms of toxic algae in Lake Erie is planktothrix, the most dominant one in Sandusky Bay.
Like microcystis, planktothrix produces the algal toxin microcystin. But planktothrix, for reasons unknown, “behaves very, very differently on how nutrients affect the bloom.”
Mr. Bullerjahn said it’s ironic the lake has two types of algae with very different evolutionary backgrounds that produce the same toxin.
Those attending in the morning included Ohio Sen. Randy Gardner (R., Bowling Green), state Rep. Steve Arndt (R., Port Clinton), and aides for U.S. Sen. Rob Portman (R., Ohio), U.S. Sen. Sherrod Brown (D., Ohio), U.S. Rep. Marcy Kaptur (D., Toledo), and Ohio Gov. John Kasich.
The afternoon session included other leading Great Lakes algae scientists who did not speak, such as Tim Davis of NOAA’s Great Lakes office in Ann Arbor and Mike McKay of Bowling Green State University.
Dave Spangler, a charter boat captain and member of the Lake Erie Charter Boat Association, told the Ohio Lake Erie Commission in late June that Lake Erie’s water quality appears to be gorgeous because of the lack of algae. He said that underscores the need to keep reducing agricultural runoff.
Mr. Spangler reiterated those thoughts for The Blade at Stone Lab on Thursday.
He said he and seven other charter boat captains who pull samples weekly determined the average depth for clear water between Maumee Bay and Kelleys Island was an astounding 14 feet about three weeks ago.
One spot near Rattlesnake Island had visibility for 20 feet, Mr. Spangler said.
During a strong algal bloom, water clarity virtually doesn’t exist.
“Nature’s telling us where the problem’s coming from,” Mr. Spangler said. “When you give [Lake Erie] a chance to flush itself out, the lake gets back to the way it’s supposed to be.”