The concept of ecological indicator species was foreshadowed long ago by using canaries — small tropical birds, sensitive to invisible gases that could kill miners — to warn the men if carbon monoxide levels were dangerously high. An expression some of us absent-mindedly use, “the canary in the coal mine”, comes from that rather exploitive history of animal use.
Other small winged creatures, bats — Earth’s only true fliers among mammals (“flying” squirrels of North America and Asia and “flying” lemurs of Asia being expert gliders) — may be inadvertently playing a similar role in modern society. Bats in the Adirondack Park, particularly, depend largely these days on artificial subterranean chambers for hibernacula, perhaps largely because many of their original winter homes were somehow usurped or destroyed by people. Before recent die-offs of bats, many thousands of several species gathered each winter in old mine shafts from the era of iron and graphite mining. These old mines function for bats much like caves do, deep enough to have constant temperatures and humidity levels. (For more background on bats, see Katie Shepard’s earlier blog on this site, Fish & Wildlife Service’s White-nose Syndrome website, and Bat Conservation International’s website and publications.)
Aliens Undermining Bat Populations
Then, tragically, about twelve years ago a tourist inadvertently carried an alien fungus (likely on his or her shoes, after visiting a cave in Europe) into one of New York’s natural but commercialized caves. Thus, evidence suggests, was white-nose syndrome (WNS) brought to the United States; and since its arrival in New York, it has spread like the plague through hibernating bat colonies across the East and Midwest. The alien fungus has precipitated a biological meltdown, affecting most hibernating bat species in the East, with effects cascading down the food web.
Because of this one barely visible invasive species of fungus, millions of bats have suffered lingering hunger and hypothermia and death. Populations have plummeted. Fortunately, individuals of some bat species are showing resistance; and researchers now think some populations may at least partially recover. For the Northern Long-eared Bat, however, extinction is a dire possibility, as few individuals of that species show resistance to the pathogen. Its cousin the Indiana Bat was already listed under the federal Endangered Species Act, and is now in still more trouble.
A cold hard lesson from this ecological disaster is that global trade and travel mean moving species around in ways that can wreak havoc for our wild neighbors. Another difficult reminder is that some habitats are so sensitive and critical that we should just stay out of them — such as where bats or snakes or other species susceptible to human disturbance congregate to sleep away the winter.
All bats are highly mobile (volant, if you want the fancy word for flying!), and even the winter hibernators migrate at least short distances between summer and nursery roosts and winter homes. These movements, too, urge us to live with careful consideration for our wild neighbors. Giant wind turbines have been shown to harm migrating bats (suggesting that energy production should be at residential and local scales, as well as being renewable). Bats will have a better chance of recovering from the scourge of white-nose syndrome if we protect large intact forests and free-flowing waterways, as we are doing relatively well — but not yet well enough — in New York’s Adirondack Park.
Read part two in this series: “BATS: Our Flying Mammal Neighbors.”
AUTHOR’S NOTE: Special thanks to conservation biologist and photographer Larry Master not only for once again contributing beautiful photos for this blog but also for reviewing and correcting it. As always, any remaining errors are the author’s own, and not those of editors or reviewers.
Note: The content in this blog post was repurposed and a revised version is included in John Davis’s book Split Rock Wildway: Scouting the Adirondack Park’s Most Diverse Wildlife Corridor published by Essex Editions on Nov. 21, 2017. Learn more about the book and where to buy it at essexeditions.com. Watch the book trailer below.