30 May Surveying for White-nose Syndrome in Montana Bats

Recently I was able to join Montana State Biologists and Forest Service Geologists on a collaborative cave survey for the presence of white-nose syndrome (WNS) in wintering bats. Our survey for that day focused on the Lick Creek Cave system in the Little Belt Mountains of Central Montana. White-nose syndrome is a disease caused by the fungus Pd (Pseudogymnoascus destructans) which manifests in a mold-like substance growing on the bat’s exposed skin such as their wings and nose. While the disease is survivable, the growth on their skin causes the wintering bats to prematurely come out of hibernation and use too much stored energy before their emergence, often resulting in death. Bats with white-nose syndrome may do strange things like fly outside in the daytime in the winter. WNS was first discovered in North America in a cave in New York State and has spread rapidly west across the country since it’s discovery in 2006. The origins of the disease are still not fully understood but it’s believed to have come from Europe where caves have since tested positive for Pd, but local bats seem less likely to develop WNS and die. What is known is that recreational caving can foster the spread of Pd fungus spores from cave to cave if clothing and equipment are not properly decontaminated after each visit. Pd doesn’t need a bat to grow, so it can live in a hibernation area even when bats are gone. Biologists believe that the fungal spores are mostly spread by bats touching other bats or surfaces that have Pd on them. Human activity in a cave can allow for increased chances of a bat becoming exposed to Pd by the cave environment, hence the need for strict decontamination practices to be taken seriously.

Lick Creek Cave is a very popular wild cave in Montana which has left it heavily used and vandalized with graffiti, trash, and the stealing of cave formations. These actions are a constant impact to the cave system and its hibernating bats. Lick Cave is also home to the largest cave room in Montana, known as the cathedral room, adding to its popularity. With bat survival during hibernation in mind the cave has recently had a locked cage installed on the entrance to mitigate the effects of human activities during the hibernation period. The cave is proposed to be open for certain periods to allow for cave recreation during the summer months when bats would be less impacted. The location of the cave has also been removed from online maps services such as google maps, to slow the rate of visitation. Our journey up to the cave started with a steep 1-mile switch back trail leading up to the cave entrance where we donned gloves, rubber boots, and one-piece coveralls that are designated to Lick Cave and Lick Cave only, to hopefully not spread Pd to other caves we survey. The goal of the survey was to collect multiple swab samples of wings and nose areas from captured bats and swab samples from the cave environment itself to later test for Pd.  As we worked our way down into the cave, we looked for bats to swab in each of the various rooms that we discovered. Bat guano was also collected at various sections of the cave system to be tested. Captured bats were exposed to black light which causes the fungus to glow orange if present, which unfortunately was observed in every bat we captured during our survey. Descending further into the cave we passed many seemingly bottomless pits to avoid and mandatory drops, both with old frayed ropes to slightly ease your mind enroute to the cathedral room entrance. The last hurdle is a 15ft muddy wooden ladder that spans over a 30-40ft drop into darkness, don’t look down. The cathedral room is one of the most impressive cave rooms I’ve ever been in. We spent hours climbing around looking for and counting bats, since the ceiling is so high we couldn’t get swab samples. The size of this room is hard to fathom since the light from your headlamp cannot shine from one wall to the other. Sitting in this room eating some lunch we turned off all lights for a couple minutes and experienced absolute darkness, which really made me appreciate the pocket full of batteries I had for my multiple headlights for the climb out.  The total darkness is the true nature of the cave, and it makes you think how remarkable it is that the bats evolved to navigate this maze of rooms and passages and reach the outside.  In my years as a Wildlife Technician for the Forest Service this wild cave was a unique experience for me and I’m looking forward to the next caving opportunity, but after 8 hours of being underground in darkness and only one spare battery left, I was ready to get out and see the sun again. On the climb back out we all had time to reflect on the day and realized that bats are in serious trouble and it will take an enormous effort from both biologist and cave recreationalist to overcome this threat.