Some Squirmy Stowaways Got to the Arctic. And They Like It There

https://www.nytimes.com/2023/07/14/climate/invasive-worms-arctic-environment.html

By Sofia Quaglia, The New York times. 

Excerpt: Worms are ...taking over territory in the Far North that’s been wormless since the last ice age. Scientists say the expansion will inevitably change northern ecosystems, with implications for the whole planet, in ways we don’t fully understand and probably can’t undo. ...In much of the temperate world, shoveling up a clump of ground full of common earthworms is a sign of healthy soil full of flora, fungi and good bacteria. Earthworms actively contribute to soil health by munching on decaying organic matter and pooping out nutrient-rich fertilizer. But that means worms also have the potential to upend the natural balance of ecosystems in Arctic and sub-Arctic zones. For example, by encouraging the growth of certain plants at the expense of others, altering entire food webs and squeezing out rare, native flora that is already threatened by climate change. ...They can also trigger microbial activity that can help to unlock potent greenhouse gases like carbon dioxide, methane and nitrogen that are stored in the soil. ...Worms didn’t make it to the Far North on their own. Research shows that humans have been bringing them, intentionally and unintentionally, to remote places above the Arctic Circle and to sub-Arctic areas since at least the middle of the 1800s by importing soil for lawns and gardens and for use as fishing bait. Recent increases in travel to these areas can also contribute to the invasion. ...Now, as human-caused climate change raises temperatures and thaws the permafrost, the worms are getting a foothold....