Media & Education
Volume 35, Issue 1, 2016
Northern long-eared Bat
A North American bat threatened by White-nose Syndrome
The northern long-eared bat (Myotis septentrionalis) ranges from the eastern and north central United States to all Canadian provinces, from the Atlantic Ocean west to the southern Yukon Territory and eastern British Columbia. As the name suggests, this bat’s most prominent feature is its long ears. The northern long-eared bat is relatively small in size, with a wingspan of around 9 inches, and a total length of about 3.7 inches. Its fur coat is traditional in color, with medium-brown and tawny tones.
When it comes to diet, it should come as no surprise that the northern long-eared bat is a nighttime predator. They primarily fly through the undergrowth of forested areas, feeding on moths, flies, leafhoppers, caddisflies and beetles. These bats will often catch their prey in mid-flight, using echolocation to find where their next meal is hiding.
As with most bats, a change in season also means a change in habitat. In the winter, northern long-eared bats hibernate in caves and mines. After fertilization in the spring, pregnant females migrate to isolated roosts or colonies underneath bark or in cavities of both live trees and snags. Here they give birth to a single pup between late May and late June. Maternity colonies of females and young generally have 30 to 60 bats at the beginning of the summer, although larger maternity colonies have also been observed. Northern long-eared bats seem to be flexible in selecting roosts, choosing roost trees based on their suitability to retain bark or provide cavities or crevices. This bat also roosts in man-made structures, like barns and sheds.
Across much of its range, the northern long-eared bat has incurred tremendous losses due to the devastating impacts of White-nose Syndrome (WNS). Since symptoms of the disease were first observed in New York in 2006, WNS has spread rapidly from the Northeast of the United States to the Midwest and Southeast, as well as across the Southeast and middle of Canada—an area that includes the core of the northern long-eared bat’s range. Losses for northern long-eared bats due to WNS have been as high as 98 percent in some parts of its distribution—a result so severe that this species was listed as Threatened under the U.S. Endangered Species Act in April 2015.
Actions, such as closing caves to human access, have been taken to try to slow the spread of WNS through human transmission of the fungus into caves. Anyone who enters a cave in a confirmed or suspect WNS-affected state or region should decontaminate his or her gear according to U.S. Fish and Wildlife Service decontamination protocols. Scientists and conservationist alike, along with BCI, are researching ways to control the growth of the fungus that causes WNS. Some biological controls, such as naturally occurring fungi and bacteria, are being tested and show promise as short-term management solutions. Other tools in development, such as vaccines and gene-silencing applications, may provide long-term management of the disease and fungus.
WNS is the primary threat to the continued existence of the northern long-eared bat. Prior to the arrival of WNS in North America, populations of this species were stable. However, with such severe losses from this devastating disease, other activities that posed little threat to the species before—habitat loss from logging, highway construction, commercial development, energy development, etc.—may now have a more significant impact on remaining individuals.
Although northern long-eared bats are disappearing, there is still a window of opportunity to save them. Combating WNS is crucial. While we search for solutions, protecting roosting sites is the next important conservation action. For instance, hibernating bats should be left alone, and their hibernation sites should not be entered during the winter months. And whenever possible, dead or dying trees should stay rooted in the ground to provide shelter for bats during the summer. If the latter is not an option, installing bat boxes can provide additional roost sites, especially from April to August, when females are actively searching for safe and quiet places to give birth to their pups.
Remember: By inspiring communities to learn more about endangered bat species, like the northern long-eared bat, and the important ecological roles they serve, we are one step closer to saving them.
Help protect the northern long-eared bat
As White-nose Syndrome threatens species across North America, protecting bat habitat has never been more important. Healthy habitats give our bats the best fighting chance maintain vital populations in unaffected areas and to help those recover in regions affected. Please help us protect the places our bats call home by donating today!
For more on Whitenose Syndrome, including how to decontaminate gear covered with the fungus, visit batcon.org/wns.
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