Response of endemic and exotic earthworm communities to ecological restoration
- Published
- Accepted
- Subject Areas
- Biodiversity, Conservation Biology, Ecology, Soil Science, Zoology
- Keywords
- Interspecific competition, Earthworm biomass, New Zealand, Soil fauna, Recolonisation, Earthworm abundance
- Copyright
- © 2016 Boyer et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2016. Response of endemic and exotic earthworm communities to ecological restoration. PeerJ Preprints 4:e2017v1 https://doi.org/10.7287/peerj.preprints.2017v1
Abstract
New Zealand has 23 exotic and more than 200 endemic earthworm species. Endemic earthworms disappeared quickly after vegetation clearance and land conversion to agriculture from the early C19th. Environmental changes associated with agronomic practices are believed to have been the main drivers for their disappearance. Exotic earthworms introduced from Europe have since largely replaced endemic earthworms into farming systems and have been intentionally propagated to increase production. Little is known about potential competition between endemic and exotic earthworms in New Zealand, and the capacity of exotic earthworms to extend their range into native habitats. Using two sites in the South Island of New Zealand, we investigated the impact of restoring native vegetation on earthworm communities. The study sites were Quail Island (Banks Peninsula), which has been undergoing native plant restoration for more than 30 years, and the Punakaiki Coastal Restoration Project (West Coast) where 130,000 native trees have been planted in retired pasture in the last seven years. At each site, soil samples (20 x 20 x 20 cm) were collected and hand sorted for earthworms. Sequential restoration plantings revealed that recolonisation by endemic earthworms increases with time after restoration at the two sample sites. With increasing age of the restoration, the biomass of endemic earthworm significantly increased, as did abundance at Punakaiki. However, exotic species did not disappear after restoration of native vegetation, even after 30 years in Quail Island. The persistence of exotic species leads to the cohabitation of the two communities and potential for interspecific competition.
Author Comment
This paper is an extended version of a short communication currently under revision in the journal Restoration Ecology.
Supplemental Information
Earthworm sampling data
Earthworm counts and biomass from 12 sampling sites in Punakaiki and 12 sampling sites on Quail Island