Most Earthworms Are Invasive, What Does that Mean for Ecosystems?

We generally think of earthworms as beneficial and essential to healthy soils–and in many ways they are! But did you know that much of the United States isn’t actually supposed to have any earthworms?

As the Atlantic reported,

“Until about 10,000 years ago, a vast ice sheet covered the northern third of the North American continent. Its belly rose over what is now Hudson Bay, and its toes dangled down into Iowa and Ohio. Scientists think it killed off the earthworms that may have inhabited the area before the last glaciation. And worms—with their limited powers of dispersal—weren’t able to recolonize on their own.”

So that means one thing: we’ve brought all sorts of earthworms to North America and not all of them are happy little soil creators. While gardeners love earthworms, they’re not quite so beneficial for forests, especially invasive jumping worms

What’s Happening: A globalized world means that earthworms have wound up all over the world–European earthworms now live on every continent except for Antarctica. But here’s the issue, as the Atlantic explained it: 

  • Although earthworms can be helpful for breaking up compacted soils and breaking down organic matter, worms can also cause trouble in agricultural fields.
  • Their burrows create channels that allow nutrients and pesticides to leak from fields into nearby waterways, and carbon dioxide and nitrous oxide to escape into the atmosphere.
  • In fact, a 2013 review of recent research found that worms likely increase greenhouse-gas emissions.

Jumping Worms: One the of most egregious invasive worm species are jumping worms, which are known for the violent way in which they wiggle. As Nature explained,

  • Jumping worms, consisting of various non-native species from multiple genera, have become established in a number of eastern and southeastern states. In 2013, species from the genus Amynthas were confirmed for the first time in the Upper Midwest, at the University of Wisconsin-Madison Arboretum.
  • In the forests and prairies of the Upper Midwest, the jumping worm could significantly alter habitats and decrease biodiversity.

What’s even more startling is that farmers are reporting that jumping worms are killing their crops in ways that European earthworms never did. 

Why This Matters: It’s still unclear about all the impacts that invasive earthworms might have on ecosystems. For one, there’s a chance they could speed up climate change as they speed up the process of decomposition in soil and release CO2 as a result. On the other hand, worm casings may be able to sequester carbon in the soil. We wrote earlier this week about the challenges we’ll face in managing nature and biodiversity in the climate change era, looks like we have to add worms to the list! 

Up Next

Advocates Urge Shipping Speed Limits to Protect Endangered Gulf Whale

Advocates Urge Shipping Speed Limits to Protect Endangered Gulf Whale

By Amy Lupica, ODP Staff Writer

A coalition of environmental groups is urging the National Oceanic and Atmospheric Administration (NOAA) to set an 11.5 mph limit on shipping speeds in an 11,500 square mile stretch of water off the Gulf Coast of Florida and Alabama. 

Why This Matters: Whales, despite operating at the top of their food chains, face mass casualties and mortal threats from human activity.

Continue Reading 554 words
UK Formally Recognizes Animals as Sentient Beings

UK Formally Recognizes Animals as Sentient Beings

by Natasha Lasky, ODP Staff Writer The UK government is formally recognizing animals as sentient beings for the first time — a major win for animal welfare activists. This announcement comes along with a series of bills that ensure the health and safety of Britain’s animals, including microchipping cats, stopping the ownership of primate as […]

Continue Reading 397 words
Idaho Governor Sign a Law Allowing Hunters To Kill 90% of the State’s Wolves

Idaho Governor Sign a Law Allowing Hunters To Kill 90% of the State’s Wolves

Idaho Governor Brad Little has signed a law that could allow private hunters contracted by the state to kill 90% of the state’s wolves. Those in favor of the measure, including lawmakers, ranchers, and hunters would like to reduce the state’s 1,500 wolves to 150, to bring down the number of attacks on livestock and deer. 

Why this Matters: This law is a step back for wolf conservation— Zoe Hanley of the Defenders of Wildlife said in a statement that this decision “marks a low point for gray wolf recovery in the U.S.” 

Continue Reading 450 words

Want the planet in your inbox?

Subscribe to the email that top lawmakers, renowned scientists, and thousands of concerned citizens turn to each morning for the latest environmental news and analysis.