Most Wisconsinites have experienced the phenomenon: hopes for a refreshing dip in the lake spoiled by floating mats of green scum, plans for a summer picnic ruined by the faint smell of rot, or a sign on a lakefront warning residents not to let their pets venture too close to shore. Many of the state’s best-known lakes suffer from these algal blooms, including Lake Winnebago, Green Lake, and Lake Monona. Even Lake Superior, known for its clear waters, has experienced algal blooms in recent years. Sometimes blooms are more than unsightly—they can be dangerous. Blue-green algae, or cyanobacteria, contain toxins that are dangerous to humans and animals, forcing the closure of beaches when levels grow too high. In Wisconsin and around the country, harmful algal blooms, or HABs, have impacts…
