Algae on Quaker Lake

A view of a suspected blue-green algal bloom on Quaker Lake in Allegany State Park on July 3. The blooms are relatively common on the area’s water bodies, but can produce toxins that can be harmful to humans and animals.

Several blue-green algae blooms were reported earlier this summer in Cattaraugus and Allegany counties, while nearby water bodies continue to see blooms of the one-celled creatures.

Cyanobacteria, or blue-green algae, came to prominence in the last week after three dogs were killed after ingesting the bacteria in a North Carolina pond.

Two suspicious small localized blooms were reported July 3 in Quaker Lake — one at the dam on the northern end of the lake, and another at Quaker Beach.

A suspicious bloom is one DEC staff have determined could contain harmful algal blooms based on reports or photographs, but lab analysis has not been conducted. A small localized bloom covers only a small area of a waterbody.

A confirmed large localized bloom was reported by the volunteer-run Citizens Statewide Lake Assessment Program on July 9 near the Caneadea Dam on Rushford Lake. Confirmed blooms are those with water sampling results confirming cyanobacteria, which may produce toxins. Large localized blooms may appear around an entire cove or a large segment of a shoreline.

No illnesses have been reported in connection to any of the local blooms this year, and the blooms have not been reported again.

Blue-green algae is believed to be one of the earliest forms of life to evolve on Earth, coming into existence between 3.5 billion and 2.1 billion years ago. Using photosynthesis, which converts carbon dioxide and water into sugar for energy, the bacteria are believed to have been involved in converting the early atmosphere of the planet into one rich in oxygen.

While some species of blue-green algae are harmless, others produce toxins that can pose health risks to people and animals if swallowed, touched or inhaled while swimming. Deaths to livestock and pets have been reported when the animals consume large amounts of algal scum from shorelines. This includes a case in Wilmington, N.C., when three dogs died after swimming in a pond with an algae bloom.

However, there are no confirmed human deaths from algal toxins.

The DEC reports that cyanobacteria are often found in small quantities in most bodies of water, but can bloom in warm, shallow, undisturbed water that receives a lot of sunlight. The blooms only occur in the hottest part of the summer, limiting the number occurring in the state.

A number of active blooms have been reported across the state, including several on Chautauqua Lake and on several of the Finger Lakes.

Algal blooms are hardly a new occurrence in the region.

Most large bodies of water in the region have seen blooms in the past seven years reported on the DEC’s website.

The Allegheny Reservoir sees almost yearly blooms, but none have been reported yet this summer. Quaker Lake and Red House Lake in Allegany State Park have seen frequent blooms. Lime Lake in the town of Machias has reported blooms in 2013, 2014 and 2017. Beaver Lake in the town of Freedom saw two blooms in 2012.

In Allegany County, observers have recorded blooms on Alma Pond in 2012, Andover Pond in 2015 and 2016, and Cuba Lake in 2015.

The blooms discolor the water — in blue-green, yellow, brown or red, depending on the species. Sometimes, the colors can be so thick it appears as though paint were spilled on the water. Occasionally, masses of the cyanobacteria can form floating rafts or scum on the surface of the water.

Unpleasant tastes or odors are not reliable indicators, nor are the absence of unpleasant tastes and odors an indicator that blue-green algal toxins are not present.

Gastrointestinal distress and contact dermatitis are the most common side effects in humans, usually resolving in a day or two. Eating fish that were living in waters with algal blooms have also caused side effects in humans.

The DEC recommends not drinking, preparing food, cooking or making ice with untreated surface water, regardless of signs of algal blooms. Field water treatments like boiling, chlorine and filtration are often ineffective against the toxins, while public water treatment systems can safely remove them. If coming into contact with blue-green algae, the DEC recommends rinsing thoroughly with clean water, seeking medical attention if symptoms include vomiting, nausea, diarrhea, skin, eye or throat irritation, allergic reactions, or breathing difficulties occur after drinking or having contact with blooms or untreated surface water.

To report a suspected algal bloom, email, and any health symptoms to and the local health department.

(Contact reporter-editor Bob Clark at Follow him on Twitter, @OTHBob)