We know the drill. Some days we see a beautiful blue Lake Stanley and other days we see the floating masses of green particles against a backdrop of brownish water and think, “yuck.” But we should really be thinking “yay,” because what we’re witnessing is an important part of the pond ecosystem: algae.
While certain types of algae can be bad for ponds and lakes, what we have at Airlie is a beneficial type called planktonic algae.
Planktonic algae are sometimes confused with muddy water because they often cause the water to look green, brown or reddish in color. They grow very quickly when conditions are optimum in the summer, often resulting in a “bloom” where the pond water becomes cloudy or colored within a day or two. These blooms usually disappear around the first frost, causing the pond to clear up very quickly — sometimes overnight.
Planktonic algae provide important benefits to the pond ecosystem as food for zooplankton (microscopic animals) which, in turn, become food for fish. Thus, ponds with abundant planktonic algae are often able to support larger populations of fish that grow more quickly (1).
Judging by some of the fish guests have pulled out of Lake Stanley, we can estimate that our algae is doing its job.
While it’s natural to assume that the green particles that appear on the lake’s surface are also algae, they are actually a plant called watermeal, according to Hunter Poland, an environmental scientist for Solitude Lake Management. “Many times we see influxes of watermeal after rain events,” Hunter explains. The green growth — which we affectionately call the “Shrek Effect” — apparently flows downstream from Lake Airlie.
But, we get it, algae and watermeal can be unsightly at times. So we recently redesigned Lake Stanley’s outflow structure to allow for a larger release of the plants. And some new water features will support aeration while keeping large masses of algae at bay. Aeration is a valuable technique for improving general water quality and the aquatic environment for fish and other aquatic life. (2)
Learn more about Airlie’s green initiatives and commitments to sustainability here.