Threadlike filamentous green algae growing in the shallows of Copley Retention Dam. These soft strands consist of a chain of cells, giving a thread-like appearance. Oxygen production as a by-product of underwater photosynthesis creates buoyancy, causing the strands to incline toward the surface.
For more information on the fascinating world of algae, see the report Field guide to algae and other “scums‘ in ponds, lakes, streams and rivers by Miriam Steinitz Kanna and Nicole Lenca of Northern Kentucky University.