Ive heard zebra mussels are causing the blooms. How does that work?
– Zebra mussels have been implicates as a factor promoting the formation of harmful algal blooms in the Great Lakes region, particularly for low-phosphorus inland lakes. By removing natural competitors (green algae) and/or altering the chemical composition of the water, zebra mussels may promote HABs. Zebra mussels have been shown to be capable of selecting which algae they consume — spitting out presumably toxic forms such as Microcystis. By filtering the water, zebra mussels also increase the amount of light reaching the bottom of the lake, which promotes the growth of large benthic forms of algae such as Ciadophora which may break free during storms or due to wave action to form floating mats or wash up on the beaches.
