Tracking Invasive Pheretimoid Earthworm Species in New Brunswick, Canada: Impacts on Soil Properties and Other Invasive Earthworms

Jumping worms, a group of invasive earthworms, are spreading northward in North America, yet their impacts remain poorly understood, especially at their northern range limit. Following the initial detection of jumping worms in New Brunswick, we sampled 46 sites across the province to assess their regional spread and examine possible vectors of dispersal. Using a combination of mustard extraction plots and timed searches targeting favorable habitats, we found them only at compost facilities, nursery/garden sites, and lawns. This suggests that the compost and nursery trade may be key vectors involved in their spread. In addition to this, we monitored jumping worm presence over a 3‐year period in a backyard in New Brunswick, where they were first discovered in 2021. This allowed us to calculate a baseline spread rate of 5 m per year. Additionally, the study revealed that neither jumping worm abundance nor biomass directly affected European earthworm populations, but year was deemed a significant predictor, with both European earthworm abundance and biomass declining with time. Additionally, we found that jumping worms had no impact on soil carbon or nitrogen over this 3‐year period. Overall, this project provides one of the first multiyear assessments of the ecological impacts of jumping worm invasion at their northern range limit.