Smooth Greensnake

The Peggy Notebaert Nature Museum of the Chicago Academy of Sciences is conducting research to understand their habitat associations, how the snakes respond to different forms of habitat restoration management, and examining different approaches to conserving and reestablishing their populations in restored grasslands. Part of this work entails monitoring their nests in the wild, incubating snake eggs to improve their survival, and raising juvenile snakes for eventual release into the wild.

Smooth greensnakes are small snakes that live in the prairies of Northeastern Illinois. If you’re lucky, you may see the flash of green moving through the grass as these snakes slither to and from nesting sites and bask in the summer sun. Unfortunately, these emerald flashes are becoming rarer in Illinois. Like many of the animals that rely on Illinois’ once vast prairie land, their habitat is now threatened by human development and changing climate conditions. That is why Dr. Allison Sacerdote-Velat and her team at the Peggy Notebaert Nature Museum are working to save them.

The team at the Nature Museum is working to save the smooth greensnake’s Illinois population by monitoring existing populations, surveying the areas that could support a population and headstarting young snakes from eggs of wild adults and supplementing them back into their parents’ site in the wild. The team is also working to reestablish populations in historic grassland locations that have been restored. By incubating and hatching eggs, this program is able to overcome the most vulnerable time in a snake’s life cycle. The Museum is currently operating programs in DuPage and Lake County.

In late April/early May, the Nature Museum team typically begins surveys of the prairielands to monitor populations and to find adult snakes that will lay eggs. The snakes tend to start nesting in ther fourth week of June. Hatching generally starts in the third week of July and continues into mid-August. This is a very busy time for researchers, because nesting and hatching can occur throughout the time period. Researchers monitor wild nests every two to three days until hatching is completed, typically in mid-August. The team continues monitoring the population until the first frost in October, when the snakes begin to overwinter.

By monitoring the populations closely, we can discover new information about the snakes and the other species they associate with in regional grasslands. The team recently discovered that smooth greensnakes have a nesting association with the Citronella ant. The snakes seek out the nest mounds of ants and deposit their eggs inside the ants’ galleries. The ant mound may provide thermal and moisture conditions that promote smooth greensnake egg survival.

Smooth greensnakes protect the prairies by feeding on small leaf-eating insects, such as crickets and smooth-bodied caterpillars. By keeping these populations in balance, plants are healthier and thrive in the prairie. Other species in the ecosystem, including birds, rely on the smooth greensnake population as a food source.

The snakes are, however, very picky about their weather and land conditions. As a result, land management for the species is a significant challenge. If conditions become too dry during nesting, eggs will shrivel up. If too large an area is burned at once, it may leave snakes with insufficient cover from predators. If an area becomes too overgrown with plants, basking and nesting sites become too shaded for the snakes. One technique restoration managers use to maintain this balance is through controlled burns of prairie areas in a mosaic rotation.

Funders and partners include: Lake County Forest Preserve District and Citizens for Conservation

Partners include: Forest Preserve District of DuPage County, Fermilab, McHenry County Conservation District and DeKalb Forest Preserve District