Algae is usually just a fact of life when visiting natural bodies of water, whether it be the ocean, a lake, or a swimming beach at one of our New York State Parks. Unhealthy ponds can sometimes be choked with thick layers of goopy green algae but, for the most part, algae are a harmless and valuable part of a healthy ecosystem.
Some algae, however, produce toxins that are dangerous for people and animals. Blue-green algae (BGA) is one of these. BGA isn’t really an algae at all. It is a little organism called a cyanobacteria which which is naturally present in low numbers in our freshwater ecosystems.
Like algae and other plants, these bacteria create energy using photosynthesis, but unlike plants, some species of cyanobacteria produce harmful toxins. In bodies of water with unnaturally high levels of nutrients, usually caused by fertilizers, stormwater runoff, or faulty septic systems, BGA can discolor the water and form a visible scum across the water’s surface. This is called an algal bloom.
Blue-green algae can be blue-green or green-brown in color, often resembling pea-soup. Unlike non-toxic algae, which is stringy or hairy in texture, blue-green algae is slick and slimy, appearing as spilled paint on the water’s surface. BGA is often accompanied by a musky odor. However, BGA can vary in appearance, and so all suspected BGA blooms should be avoided.
Unfortunately, many BGA incidents have directly affected dogs. Swimming in BGA-affected waters is risky for humans and pets, but dogs are more likely to jump into slimy and foul-smelling water, and then lick the algae off their fur. Contact with BGA can cause rashes and swelling, and ingestion can lead to difficulty breathing, stomach pain, nausea, and in severe cases, convulsions. Ingesting BGA can be fatal for dogs, and so if you suspect your pet has come into contact with BGA, wash her off with clean water immediately.
The best way to prevent BGA blooms is to prevent nutrient runoff into water bodies. Monitoring is being conducted around the state by state park staff and by private citizens.
If you see a suspected BGA bloom, be sure to keep children, pets and livestock away from the water. If you’re in a State Park, notify a lifeguard or any park staff immediately, or contact the Environmental Management Bureau’s Water Quality Unit (Water.Quality@parks.ny.gov; (518) 474-0409). Otherwise, contact your regional DEC office (http://www.dec.ny.gov/about/50230.html) or the Division of Water (518-402-8179)