PLATTSBURGH — The season’s early closure of public beaches in Port Henry beach due to blue-green algae may be a harbinger of things to come.

Both the Town of Moriah and Village of Port Henry beaches were closed by the New York State Department of Health Tuesday when tests verified the presence of blue-green algae, which can contain toxins that are harmful to humans.

And conditions for blue-green algae are ripe all across the lake.

“There have been several (blue-green algae) blooms identified throughout the southern main lake, south of Essex-Charlotte Ferry,” said Mike Winslow, scientist for the Lake Champlain Committee, which has organized a lake-wide volunteer monitoring system for blue-green algae.

“We’ve also seen blooms in Westport and Willsboro, places that we don’t usually see them.”

NUTRIENTS A FACTOR

Algae blooms have more often been identified in the shallow bays in the northeastern sections of Lake Champlain, where levels of such nutrients as phosphorus are typically higher. Deep, colder water found in the main lake contains fewer nutrients and is less likely to support algae blooms.

Recent changes in the lake may have contributed to a change in algae locations, Winslow noted.

“There are three things going on this year (that may be promoting algae-bloom shifts),” he said. “For one, we’ve had a really warm spring, and it has been really hot lately. Also, the lake water is quite low, which might promote an increase in blooms, and there is still a ton of stuff in the lake from Hurricane Irene and last spring’s flooding.”

STAY AWAY

Not all blue-green algae contains toxins that can cause skin irritations, stomach aches and other health concerns in humans. The only way to confirm whether a bloom is toxic is through testing, and conditions in an algae bloom can change by the time a test is completed, Winslow said.

“The best thing to do is to stay out of green, scummy water.”

Pet owners should also keep their dogs out of water that may be infested with dangerous blue-green algae. Dogs will often lick themselves dry after entering a body of water, and they can ingest large quantities of toxins that way, Winslow said.

A pair of dogs died several years ago after swimming in water infected with blue-green algae at Point au Roche in Beekmantown.

VOLUNTEERS NEEDED

The Lake Champlain Committee has been doing blue-green algae monitoring since 2003 but has modified the program to incorporate a visual system that identifies the potential for blue-green algae without relying on tests for confirmation.

“We’ve trained close to 100 volunteers to distinguish blue-green algae from other plants,” Winslow said. “It’s a cautious approach, but our training can provide some clues about whether what they are seeing is definitely blue-green algae.”

The committee’s website has a volunteer reporting form that anyone can use to identify the location of a potential bloom. The website also has a link to the Vermont Department of Health for a lake-wide advisory of algae blooms.

Most of the New York shoreline is covered with volunteers, but Winslow said he is in need of volunteers in the Cumberland Head area and is prepared to offer a training workshop at Cumberland Bay State Park if people in that area are interesting in monitoring for algae blooms.

“What makes this program worthwhile is that we not only want to sample areas where blooms have been identified but also where they haven’t been identified,” he said.

Winslow stopped short of predicting what the rest of the summer may bring, though algae blooms historically are more severe as the lake warms into August.

He did say the current blooms will “stick around, as long as weather conditions are calm.”

Email Jeff Meyers:

jmeyers@pressrepublican.com