Why we're not "jumping for joy" at the arrival of Jumping Worms to New Brunswick
Have you heard the latest news on Jumping Worms being discovered in New Brunswick?
Originally from Asia/Japan, these invasive worms are much larger than other non-native European Earthworms and can have greater impacts on our environment and forests. This can include impacting forest productivity, limiting plant regeneration, and displacing native wildlife and insects.
Photo Credit: Gabriel Price-Christenson, cottagelife.com
In New Brunswick, we have 7 non-native species of earthworms, which are all considered introductions from Europe (McAlpine et. Al, 2019). The name “Jumping Worms” is a catch-all term for 3 species of large jumping worms being spread across North America, which are the species Amyntha agrestis, Amyntha tokioensis, and Metaphire hilgenforfi. The name “jumping worm” comes from their aggressive thrashing and wiggling, as they “flick” their tail and move quickly through soil and break up material, causing a coffee-grind like appearance in impacted soils. Here is how they differentiate from other earthworm species:
Larger in size
More aggressive feeding habits (they have been called “sharks of the earth”)
Found in higher densities than other earthworms and can reproduce much faster
Can move longer distances and are fast moving
More adaptable as they can survive in colder temperatures and produce cocoons that can overwinter in soil
Outcompete other earthworm species
While we do have non-native earthworms in our environment currently, these Jumping Worms are cause for concern in New Brunswick and will have greater impacts, including;
Changing the structure and nutrient composition of the soil, which makes it difficult for plants and trees to grow and stay rooted
Turning up the soil, making it very dry and grainy (looks similar to coffee grounds). This will decrease the overall forest and crop productivity
Altering food webs and the species composition in forest environments, including the presence of native species
Increasing the opportunity for other invasive species introductions by disturbing the ecosystem
Impacts from an invasion of Jumping Worms are complex as they can impact food webs, nutrient cycling and decrease overall environmental quality. The diagram below communicates some of the cascading impacts that could arise from a Jumping Worm invasion in forests and other ecosystems.
Frelich LE, Blossey B, Cameron EK, et al. Side-swiped: Ecological cascades emanating from earthworm invasion. Front Ecol Environ. 2019;17(9):502-510. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6944502/
For more information on Jumping Worms in Canada, visit the Invasive Species Centre Jumping Worms page or contact info@nbinvasives.ca.
Interesting Fact: Did you know that some US states have imposed restrictions on Jumping Worms due to concerns over their threat to natural resources? They are a prohibited species in New York State and a restricted species in the state of Wisconsin.