After the steep climb along Hartman Trail, I turned to admire the scenery of Canoe Creek. On this beautiful spring morning, the wind was driving sky blue waves on the lake and ripples of silver through new field grasses. Grackles were aggravating each other, chorusing their disapproval of nearby jays, while metallic tree swallows arrowed over their nest boxes. The warm sun and peaceful scene betrayed nothing of the quiet invasion and resulting death taking place under my feet.
I was taking one of my last hikes to check on the bat mine for signs of WNS (white nose syndrome) hitting our bat colony. The PA Game Commisison (PGC) had
installed gear focused at the mine entrance to detect the
calls of bats. The emergence of bats before their usual
spring exodus would provide the park and PGC biologists
WNS has been sweeping down from the New England
states in the last few years, wiping out over a million
bats across hibernation sites in the northeast. Numbers
indicate that once WNS finds its way into a wintering
Scientists still cannot agree if the fungus that appears on bat muzzles and wings is the cause of death. Somepropose that the white fungus appears on the bats after their systems are weakened from starvation. It may be possible that pesticides accumulate in the bats' tissues, increasing their metabolism and forcing them into starvation before outside temperatures are warm enough to provide them the insects they need.
Crossing the ridge, I circled down the dirt road to the mine entrance. The tightly fitted gate, only five feet high and eight feet wide, was designed to stop intrusion of predators (mostly human) into the hibernating colony. However, the bat gate, now a standard measure across the country for protecting wintering colonies, was not designed to prevent against disease such as WNS. The last 50 or so years of studying bats have shown us that we reap incredible benefits from services they provide as they cull insect populations. The US Forest Service estimates that because of WNS, 2.4 million pounds of insects will go uneaten and become a financial burden to farmers. Crop production will require more insecticides, raising food costs and increasing untold environmental concerns. In Pennsylvania, a state with an agriculture-based economy, those losses are no small thing.
As the world grows smaller, we have struggled to keep pace with the ever-increasing invasion of exotic species. Although scientists are not 100 percent certain of the origins of the fungus that causes WNS, many believe that it originated in Europe and reached U.S. caves via tourists and cave enthusiasts. If that is the case, WNS will qualify as one of the many thousands of invasive species from all kingdoms of life rearing its ugly head, wreaking untold havoc with natural systems.