A Perfect Day for Cerceris Wasp Training

Claire Rutledge, an entomologist at the Connecticut Agricultural Experiment Station (CAES) led the Cerceris Wasp Workshop on Thursday, June 28th at White Memorial. Fifteen volunteers came to the training session to learn how the Cerceris fumipennis wasp can be utilized to survey native buprestid diversity. The wasps also act as an early detection device for other invasive buprestid such as the Emerald Ash Borer. After a short introductory presentation, the group traveled to St. Anthony’s Cemetery on White’s Woods Road, where a colony of the ground-nesting Cerceris wasps were known to inhabit.

Claire Rutledge, surrounded by volunteers, placing a collar over a Cerceris wasp hole.

On a tightly packed dirt road in the back of the cemetery we were able to find many wasp holes. The goal of this project is to spot a Cerceris wasp flying back to its colony carrying a beetle as its prey. Using aerial nets we want to try to catch or startle the wasp enough to release the beetle so that it can be collected and sent to the CAES to be identified and examined. Along with the nets, collars can also be used to gather the beetles. The collar is a file card with a hole punch tacked on top of a wasp opening, the hole punch is small enough for only to the wasp to fit through forcing the wasp to forfeit its prey. This technique of robbing the wasp or selective prey removal will not significantly alter the wasp’s provisioning behavior. Cerceris wasps are most active during July and into early August, so during this time colonies must be visited as often as possible to get the goal of capturing 50 beetles. Wasp activity is greatest when there is direct sunlight, between 11 a.m. and 5 p.m. Since the wasps are typically found on hard packed sandy soil; baseball/softball diamonds, informal parking lots, camp-sites, and road edges are excellent locations to look for a wasp colony.
Cerceris wasp hole.
Cerceris wasp caught in a net by a skilled volunteer.

No comments: