Cindy Johnson-Groh, a biology professor, led surveys in Tettegouche State Park and George H. Crosby Manitou State Park with her Superior Studies class in 2000. The two sample plots in Tettegouche were located in front of what is believed to the leading edge of an earthworm invasion from an old fishing resort. An additional two plots were sampled in George H. Crosby Manitou State Park. No worms were found in the two sample plots on each site.
Location: Tettegouche State Park, MN
Lead Researcher: Cindy Johnson-Groh
Barbara's students did a wonderful study to see how the change in the season affected earthworm activity. On November 12, 2007 they collected earthworms from three sample plots in a wooded area near their school. They sampled the same plots again on November 29th after the temperatures had gotten a lot colder. They preserved their specimens from each sample date and sent them to us with the latitude and longitude of the area sampled and a wonderful description of their study, click here to read their report.
On November 12th, the student collected 207 earthworms, including 10 species and 40 hatchlings (baby worms).The species/groups included Lumbricus terrestris, Lumbricus rubellus, Lumbricus juveniles, Eiseniella tetraedra, Dendrobaena octaedra, Aporrectodea rosea, Aporrectodea tuberculata, Aporrectodea juveniles, Octolasion cyaneum, Octolasion juveniles. Clearly there are lots of earthworms there, which probably reflects the long human history on the site. The most interesting species was Eiseniella tetraedra, which is fairly rare compared to the other species.
On November 29th, after air temperatures had begun to drop rapidly, the students collected just 10 earthworms from the same area which really illustrates how earthworm become much less active as the winter approaches. The only species found that day included Aporrectodea juveniles and Octolasion cyaneum, two soil dwelling earthworms which live deeper in the soil so are affected by droping air temperatures less quickly than species that spend more time near the surface.
Dr. Hale identified their earthworms and sent them back to the students so they could use them as voucher specimens for a follow-up study they plan to do in April 2008. Nice job!
Location: Golden Valley, MN
Lead Researcher: Barbara Jacobs-Smith 3rd grade Class