Over the last several years, we have observed an increase in lake foam on Canandaigua Lake. Scientific analysis has determined that the foam is of biological origin, and is not dangerous or toxic. But….
Just what is that foam anyway?
The foaming of surface waters on lakes is not a new phenomenon. It is a natural process that has been going on for a long time in many different parts of the world. Foam is created when the surface tension of water (attraction of surface molecules to each other) is reduced and the air is mixed in, forming bubbles. When organisms, such as algae, plants, fish and/or zebra mussels die and decompose they release cellular products (surfactant) into the water, which reduces the surface tension. When the wind blows, the waves on the lake agitate this surface agent, thus transforming it into sudsy white foam. Currents and boats also mix air with the organic compounds present in the lake to produce foam. The foam will frequently form parallel streaks in the open water, caused by wind-induced surface currents. It will also collect in large quantities on windward shores, coves, or in eddies. This is especially true on the east shore of Canandaigua Lake. Over the past years Skaneateles Lake, Cayuga Lake, Keuka Lake and Oneida Lake have also experienced foam. We have also had substantial foam on the lake in September of 2001 and then again in 2006. We have periodically seen foam in recent years as well.
In 2002, the Watershed Council worked with Dr. Greg Boyer, a leading researcher from the State College of Environmental Science and Forestry in Syracuse, to collect and analyze foam samples from Canandaigua Lake. The purpose of the research (included Dr. Bruce Gilman of FLCC, and Webster Persall of DEC) was to try to scientifically link the production of foam to its source. Samples were analyzed for organic matter, lipids, protein, carbon, carbohydrates, fatty acids and nitrogen. The chemical testing on the foam however could not definitively pinpoint the source of the foam, but did show a mixture of plant and animal organic matter. Results did rule out any man-made sources.
There are two main theories we are investigating. We are going to try to determine if there has been a die off of Quagga Mussels that cumulatively excreted large amounts of surfactants (organic matter) into the water creating the foam. The second theory is that ecosystem changes brought by Quagga Mussels, such as an increase in blue-green algae, may also be a contributing source. In 2001/2002, we documented a temporary Zebra Mussel die-off through age-classification of Zebra Mussels in the Lake. Analysis performed by Finger Lakes Community College showed that the overwhelming population of living Zebra Mussels collected in eight different lake locations was less than six months old. We are going to try to do the same analysis for Quagga Mussels which have largely replaced Zebra Mussels in the lake.
-Kevin Olvany, Canandaigua Lake Watershed Council