By Janet Battista
Friends of Lake View Hill Park
Cool and dry, the nurses’ dormitory tunnel at Lake View Hill Park seems an ideal winter bat home. But according to Department of Natural Resources (DNR) bat conservationist Jennifer Redell, bats haven’t found the tunnel yet. On March 14, Redell, along with two Dane County Parks’ employees and several Friends of Lake View Hill Park (Friends), conducted a 5-year inspection of the abandoned tunnel.
Between 1934 and 1966, nurses working at the old tuberculosis sanatorium — now the Dane County Human Services Building — lived at the “Dormitory for Help.” They used the tunnel for easy back and forth access between the dorm and the sanatorium to care for the patients housed there.
By the 1960s, antibiotics had almost entirely eliminated tuberculosis; and in 2016 Dane County demolished the crumbling nurses’ dormitory. All that remains of the building is a terrace saved as a memorial to the nurses. You can see the memorial and its beautiful site just east of the Dane County Human Services Building at 1202 Northport Drive.
Before the scheduled demolition, members of the Friends group, remembering the tunnel, alerted Redell to its presence. They wondered whether it could be used as a home for bats. With encouragement from the Friends and DNR staff, Dane County agreed to save the tunnel.
Redell oversaw modifications, including installing a baffle to help keep hot air out, and adding a steel cupola over the exposed entrance. The cupola allows bats entry but keeps vandals and critters out. Staff can access the tunnel via a door in the basement of a maintenance building nearby.
Wisconsin has eight bat species, and four of them overwinter in caves (hibernacula). According to Redell, the tunnel makes an ideal hibernaculum due to its location at the top of Lake View Hill overlooking Lake Mendota to the south and surrounded by native woodland to the north.
Redell expects little brown bats to show up at the tunnel first. Voracious insect predators, little brown bats have a crucial role in a healthy ecosystem by reducing insect populations and aiding pollination.
Since 2014, when white nose syndrome fungal disease showed up in Wisconsin, their population has declined by nearly 90%. The tunnel at Lake View Hill can provide a new bat habitat free from the devastating fungal disease. With its uniform walls and regular shape, the tunnel can be disinfected periodically as natural caves cannot.
Redell reports that although the little brown bat population has stabilized since the fungal disease first devastated their population, they still need help. As citizen scientists, the Friends will periodically monitor the tunnel for bat activity and will keep the cupola entry free of excess vegetation.
Keanan Sargent, as part of his Eagle Scout project, erected a bat house in the woods at Lake View Hill Park. Hopefully, it will help attract little brown bats to the tunnel.
For more information about Wisconsin bats and how to protect and help them, see the DNR bat program website at dnr.
wisconsin.gov/topic/WildlifeHabitat/Bats.