Biological Invasions

, Volume 11, Issue 1, pp 59–79

Distribution and impacts of invasive earthworms in Canadian forest ecosystems

Review Paper

DOI: 10.1007/s10530-008-9320-4

Cite this article as:
Addison, J.A. Biol Invasions (2009) 11: 59. doi:10.1007/s10530-008-9320-4

Abstract

In Canada it is generally accepted that most indigenous earthworms did not survive glaciation, and that the majority of the earthworms now inhabiting Canadian soils are relatively recent introductions of European origin. Although these exotic earthworms are generally considered to be beneficial in agricultural soils, their effects can be less benign in forested ecosystems. Studies have shown that invading earthworms can significantly alter the forest floor, affecting the distribution of carbon, nitrogen and other chemicals, roots, microbes and other elements of the soil fauna, and even understory vegetation. This paper summarizes the current distribution of exotic and native earthworm species in Canadian forests and draws on the results of studies of invasion patterns and environmental impacts in northern forests in North America and Europe to discuss potential outcomes for forests in Canada. The potential for variables such as temperature, pH, litter palatability and dispersal, to limit or promote the invasion of exotic earthworms in Canadian forests is discussed, and areas for future research are proposed. The same earthworm species that are invading forests in northern Europe and the US are also invading Canadian forests. Several species of exotic earthworms are already established in a wide range of deciduous and coniferous forest types, including the boreal. Evidence is presented to suggest that further expansion into Canadian forests is likely.

Keywords

BorealDistributionEarthwormsExoticInvasionNativeNorthern forest

Abbreviations

BOR

Boreal forest region

COAST

Coastal forest region

CWH

Coastal Western Hemlock Biogeoclimatic Zone

GL-ST

Great Lakes/St. Lawrence forest region

MON

Montane forest region

Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.School of Environment and SustainabilityRoyal Roads UniversityVictoriaCanada