Metaphyton

Metaphyton is a term used to describe free-floating, filamentous algae typically observed in shallow littoral areas of lakes, where it can become entangled in the stems of rooted aquatic plants (macrophytes). Metaphyton is often characterized as having the appearance of “green cotton candy.” This filamentous algae has relatively little substance, as anyone who has attempted to grasp a handful can attest. The masses, balls, or pillows can vary in size from a few inches to a dozen feet across. They are most commonly found below the water surface but will sometimes float due to entrapped air bubbles.

Metaphyton often appears in lakes soon after “ice out” and may persist through the summer, but it often begins to degrade by late summer (August-September), at which time the masses sink to the bottom and decompose, appearing as scattered brown residue.

The Lake Stewards of Maine (LSM) has developed a process to allow volunteers to identify, document, and track the growth of metaphyton in Maine lakes and ponds. The significance of possible increases in metaphyton growth in some Maine lakes is not fully understood, but interest in the role this group of algae plays in lake ecosystems is growing. Anecdotal and observational information suggests that many lakes have experienced a substantial increase in metaphyton growth during the past decade. This project will enable volunteers to gather information to help study this phenomenon.