Didymo (a species of freshwater algae) and New Zealand mud snails were recently discovered in two Michigan waterways.
"These two species have each had significant impact on native ecosystems," said Michigan Department of Environmental Quality Director Dan Wyant. "They degrade and in some cases ruin popular fisheries, and they can significantly alter the foundation of an entire waterway."
Didymo is different from many types of nuisance algae (and cyanobacteria) in that it is often present in streams and rivers with low nutrient concentrates, rather than eutrophic or high-nutrient content water. Capable of negatively affecting food sources and habitats, Didymo can be spread with a single drop of contaminated water (it is a diatom, a single celled organism).
New Zealand mud snails are also a threat to food chains, as they are known for removing algae that typically feed the insects that in turn feed species like salmon and trout.
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