December 16, 2017

Distribution of Earthworms Project

Contact: Dr. Tim McCay, Colgate University,

Initiated: 2013

This new EREN project is titled “Factors affecting the Distribution of North American Earthworms.”  The project description includes protocols (EREN Worm Project Description) for the sampling of earthworms and environmental variables potentially important to explaining the presence, abundance, and diversity of worms.  Academic year 2012-13 constituted a pilot phase for this project during which the protocol was vetted and edited. The project is now being launched in earnest starting summer 2013.  I invite you to consider participating in the project – in its entirety or in part – in your courses and with your research students.  The activities are potentially amenable to lab experiences in courses related to ecology, invasive species, conservation biology, and invertebrate zoology.

As you may know, many common earthworms in North America are believed by most scientists to have been introduced to the continent by people, and the dispersal abilities of earthworms are modest in the absence of human help.  Although earthworms are frequent guests of our yards and gardens, many remote natural areas have few or no earthworm species – especially in previously glaciated areas.  The extent to which different parts of North America are worm-colonized is not well known.  The initial phase of the project relates to the relative importance of habitat quality and biogeographic factors in affecting worm presence, abundance, and composition.  If habitat quality is predominantly important, that would suggest that the invasion has largely “played out,” and we now find worms in all of the places that suit them. If biogeographic factors (e.g., distance to the nearest road) are important, this would suggest that invasion processes are ongoing. These relationships are likely to vary with glacial history, human land use, and other factors.  So, having a network of widely distributed collaborators is advantageous.

I invite participants to work with me on this topic using the EREN collaborative approach.  Authorship on publications and presentations will follow the EREN Authorship Guidelines (  I also invite participants to think of additional ways of using the data set to look at ecosystem effects of earthworms, earthworm evolution and cryptic species, and other topics.

Earthworm Project Participants - [Updated June 2013]

View the Map of Participating Institutions

EREN Earthworm Protocol

Educational Applications:
EREN Earthworm Lab Exercise

PBS Video Featuring this Earthworm Project

Video: Distributions of North American Earthworms Part One, Sampling of Earthworms

Video: Distributions of North American Earthworms Part Two, Preservation and Identification of Earthworms

If you would like to participate or would just like to be kept in the loop, please send me an email ( copied to the EREN address ( describing your desired level of involvement.

Timothy S. McCay
Associate Professor of Biology and Environmental Studies
Colgate University
Hamilton NY 13346 USA
Tel 315.228.7705 |