Earthworm effects

We examined effects of non-native earthworms on fungi, microarthropods, and songbirds.

We found no effect of earthworms on colonization of white spruce roots by ectomycorrhizal fungi.

White spruce greenhouse experiment. Photo: Kyle Knysh

Abundance of microarthropods was 50% lower when earthworms were present versus when they were absent.

Heat extraction of microarthropods. Photo: Kyle Knysh

American robins occurred twice as often at locations with non-native earthworms present versus locations without earthworms, likely due to robins’ use of earthworms as prey.

An American robin eating an earthworm. Photo: Cory Olson