What are algal blooms?
In general, most algae are harmless and are an important part of the food web. Certain types of algae can grow quickly and form blooms, which can occur in isolated locations or can cover an entire lake. Our monitoring program has shown that in 2015 and 2016 there were only a few isolated occurrences of HABs on Seneca Lake. Unfortunately, in 2017 HABs were wide spread, covering most of the lake during the last two weeks of September.
What are blue-green algae?
Blue-green algae are not algae at all, but rather a type of bacteria called cyanobacteria. It is normal for cyanobacteria to be present in lakes. However, this type of bacteria thrives in warm, nutrient-rich water and when conditions are right, the bacteria can grow quickly forming “blooms.”
When blue-green algal blooms produce cyanotoxins, they are harmful. Last year, some of the HABs in Seneca Lake produced microcystin and anatoxin, which can cause health issues in humans and animals. If individuals or animals are exposed to HABs and are experiencing adverse health effects, they should seek immediate medical attention.
How do I know if a bloom is toxic?
Laboratory testing is the only reliable method for determining if a bloom contains toxins. If you see a suspicious bloom, report it, so a sample can be obtained and tested for toxins.
When do harmful algal blooms occur?
Blooms typically form in warm, calm waters during summer and early fall, but can occur other times of the year, if conditions are right.
HABs have different colors and looks. Some colors are green, blue-green, brown, black, white, purple, red and black. They can look like film, crust or puffballs at the surface. They also may look like grass clippings or dots in the water. Some HABs look like spilled paint, pea soup, foam, wool, streaks or green cottage cheese curd.