See inside a Minnesota bat cave

Environment Jennifer Simonson · ·

1 A little brown bat hangs on the wall at Mystery Cave Tuesday, Sept. 24, 2013 at Forestville State Park in southeastern Minn. A fungus linked to white-nose syndrome, which can wipe out bat populations, has been found at the cave and state Department of Natural Resources officials are working to prevent its spread. 
2 Mark White, a Department of Natural Resources naturalist at Mystery Cave, talks about the cave and the thousands of bats that hiberate there each winter Tuesday, Sept. 24, 2013 at Forestville State Park. 
3 A small passage above the door allows hiberating bats to enter Mystery Cave, but keeps their predators such as raccoons out, Tuesday, Sept. 24, 2013 at Forestville State Park in southeastern Minnesota. The cave is open for tours during the spring, summer and fall. 
4 While walking through Mystery Cave's passages, visitors can see formations like stalactites that hang from the ceiling Tuesday, Sept. 24, 2013. During tours dim lights are turned on to illuminate the cave's formations and passages, but otherwise the lights are off to prevent algae growth. 
5 A stop at Turquoise Lake is a highlight on the Mystery Cave tour Tuesday, Sept. 24, 2013 in Forestville State Park in southeastern Minn. 
6 A stop at Turquoise Lake is a highlight on the Mystery Cave tour Tuesday, Sept. 24, 2013 in Forestville State Park in southeastern Minn. 
7 Visitors who want to tour Mystery Cave by flashlight use this more rustic entrance Tuesday, Sept. 24, 2013 at Forestville State Park. This side of the cave, that is drier and has fewer formations, is where the first of the hiberating bats can be found in the early fall. 
8 Two little brown bats on the wall just inside the more rustic entrance Tuesday, Sept. 24, 2013 at Mystery Cave in Forestville State Park. A fungus linked to white-nose syndrome, which can wipe out bat populations, has been found at the cave and Department of Natural Resources officials are working to prevent its spread. 
9 Mark White, a naturalist at Mystery Cave, uses a flashlight to illuminate where fossils left marks on the walls Tuesday, Sept. 24, 2013 at Forestville State Park. 
10 Naturalist Mark White uses a flashlight to show off a cave formation during a tour of Mystery Cave Tuesday, Sept. 24, 2013 at Forestville State Park. 
11 A tricolor bat, a small and solitary bat, hangs from old wiring near the rustic entrance to Mystery Cave Tuesday, Sept. 24, 2013 at Forestville State Park in southeastern Minnesota.