“Rock snot” algae bloom is doubly weird: It’s native not invasive, and is triggered by too *little* nutrients

A few years ago, people started encountering disgusting blooms of an invasive algae known as didymo – blooms so disgusting they were termed “rock snot,” making the topic irresistible to reporters.

It turns out that the algae is actually native to the Northeast, not an invasive – making it the only case I’ve ever encountered in which a supposedly invasive creature was found to have been living locally for millennia.

A second weird thing: Unlike other algae, this one blooms not when too much nutrients flow into the water but when there is too little of it – which is unexpected.

And what’s making it bloom now? Find out by reading the item here.