At first glance, the waters of Glen and Fisher lakes appear as clear as distilled water. But magnified 450 times, a whole new world appears.
Since 2014, each month from April to November, watershed biologist Rob Karner climbs on board the GLA Science boat, RV Sarah, heads out on the water, plankton net in tow, to the same four spots he’s been sampling for years. Then back at the lab, Rob uses his microscope to record the presence and/or absence of the variety of tiny plants (algae) and tiny animals. Rob likes to call this, “Seeing who of my friends shows up to the party”. The hope is that each collection contains many species (biodiversity), a key indicator that life in our lakes is healthy.
Rob’s extensive data set reveals much about what goes on at a microscopic level, the base of our watershed food web. Over the past several years, the community of microscopic life indicates overall, our waters are doing well. But in the most recent decade, the diversity of algae has declined. And on occasion, especially in August and September, there are algal blooms that show up in the plankton net. These blooms have the potential to cause the water to become toxic. Keeping excess nutrients, “algae food” such as phosphorous, out of the water is an important way we can fight back and prevent toxic blooms.
For more information about monitoring the microscopic life in our lakes, contact Rob Karner, rkarner@leelanau.org
Photo Above: Microscopic Asterionella Diatoms, maginfied 450x. Photo by Rob Karner
Pieces of Fragularia and Asterionella, and Pediastrum, Fragularia, and Asterionella Diatoms. Photos by Rob Karner
