In the Driftless Area of Northeast Iowa, ancient limestone cliffs are peppered with sinkholes and caves, freshwater springs and algific talus (or cold air) slopes. This country has remained unchanged since the glaciers of the last Ice Age passed through and formed its unique geology. Even in the summer heat these hillsides remain chilly providing an ideal habitat for some species of plants and animals which have lived here undiscovered for over 10,000 years.
This landscape is rugged and therefore relatively safe from the encroachment of development and consequently this area boasts some of Iowa’s most beautiful unspoilt forests and freshwater streams. The coldest areas of the slopes are populated by abundant layers of mosses, liverworts and ferns together with balsam fir, paper and yellow birch and mountain maple.
The Driftless Area National Wildlife Refuge was established by The Nature Conservancy which owns 400 acres in the region. The Conservancy is working with the US Fish and Wildlife Service, Iowa Department of Natural Resources and other agencies to try to protect the area from threats such as logging, rubbish dumping and inappropriate grazing.
The conservationists’ long-term goal is to save sufficient cold air slope sites in order to protect the federally endangered Pleistocene snail and northern monkshood plant.
The Pleistocene snail was thought to have been extinct for 10,000 years and was known only from fossils found across the Midwest. Then in 1940, the US National Museum discovered that a live specimen had been found years earlier by Iowa naturalist, Bohumil Shimek. The precise location of his discovery was not recorded however and the trail went cold.
Then in 1955, records came to light which hinted that Shimek was in Northeast Iowa at the time of the specimen collections. Biologists were commissioned by the US Office of Endangered Species to find the collection sites, but to no avail. The mystery remained unsolved until 1980 when University of Iowa geology graduate, Terry Frest was tasked with investigating the snail. Frest not only uncovered several sites where the snail was thriving, he discovered several other species of snail which had never been seen before and were totally new to science!
All the snail species are found exclusively and in very small numbers on the algific talus slopes. The area also provides habitat for 96% of the total population of the threatened northern monkshood plant.
*Image courtesy Flickr creative commons.