Feels like it’s been forever since I posted here, and while I’ve been inspired to research many of the questions I’ve come across in recent months, this is the first time I’ve decided to follow up and write about it! So without further ado, blue green algae!

A warm hot stew at the edge of the lake

Today while out at Rock Point for Crow’s Path summer camps, our efforts to find respite from the summer heat were thwarted by a nasty sludge lapping against the shoreline. When we got to the beach, life guards from North Beach were walking up and down the beach taking photos, likely as part of the state’s blue green algae tracking efforts (see link for current reports from around the state). North Beach is a near perfect recipe for blue green algae blooms. It has a large shallow sandy beach that extends far out into the lake, with full exposure all day. It’s also sheltered from winds out of the north, south, and west by Rock Point, winds that would otherwise bring in cooler water, which would slow down reproductive rates of the cyanobacteria, or disperse the blue green algae.

We’ve had air temperatures consistently above 70 since the middle of May. The water temperature is currently above 70(!!) and with the absence of wind, the conditions are perfect for blooms. The forecast is hot hot hot tomorrow with no wind. The rains could bring wind, which would shake things up, but they could also bring in more nutrients to the lake which would feed the cyanobacteria’s growth.

Not quick the thick pea soup yet.

How do you identify it?

  • It’ll look like a greenish paste towards the surface, much like pea soup
  • When it gets super intense you’ll see what looks like bluish or greenish swaths of paint on the surface
  • Before it gets to these concentrations, the water will take a greenish hint and you can see little green dots floating in the water.

So if I see it in the water, what should I do?

  • Well, probably don’t go in the water. According to the Vermont Dept of Health there are no known cases of the blooms causing human illness, but I’d rather not take the risk as associated symptoms may include:
    • Skin rashes
    • Vomiting, diarrhea
    • Allergic-like reactions if water droplets inhaled
  • Don’t let your pet go in the water. Pets won’t know the difference and can drink the water and get ill
  • If you’re on the fence about whether or not to go in the water, definitely check with whoever maintains the beach or check the state’s blue green algae tracker

Oh, and a note about taxonomy…or maybe a warning. Michigan botanists Edward Voss said, “Common names are for common people.” Common names lead to lots of confusion about the organisms we’re talking about. Blue green algae is a perfect example. While it is bluish green, it’s not an algae. Algae alone is difficult enough. For a good exercise in frustration, try boning up on your algae taxonomy. Algae’s not a plant (no roots, no leaves), but neighter is it a true bacteria (they’re eukaryotes). Blue green algae is a bacteria, or more specifically cyanobacteria, a branch of photosynthetic bacteria. Being bacteria, they are simple organisms and super super tiny. We only get to see them when their populations get out of control.

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