Bat Population Monitoring at Marsh-Billings-Rockefeller National Historical Park

A little brown bat clinging to the side of a tree.
A state endangered little brown bat (Myotis lucifugus) clinging to the side of a tree. Since the arrival of white-nose syndrome, bats of the genus Myotis have become rare in the park.

NPS/Erickson Smith

Bats are an important part of ecosystems and food webs. Though some species of bats feed on fruit, seeds, or pollen, all of the species that live in the Northeast are insectivores. They consume huge numbers of insects every night, filling a unique ecosystem role as nocturnal insect predators. Unfortunately, a new disease called white-nose syndrome is affecting bats across the United States. To better protect bats, scientists are studying how local bat populations are changing.


Research Highlights

  • Since 2001, eight species of bats have been observed in the park. It is unclear if all of these species are currently found there.

  • White-nose syndrome has certainly reduced bat populations in Marsh-Billings-Rockefeller and may have resulted in the loss of several species.

  • Activity of bats in the genus Myotis has declined dramatically in the park. Bats in this genus are sensitive to white-nose syndrome.

How do biologists study bats? What have they learned about bats in the park?

Biologists use a variety of techniques to study bats. Special nets (i.e. mist nets) can be used to catch bats at specific sites in the park. Captured bats can reveal important information about bats. Biologists can learn when females give birth to their pups (bat babies), the locations of roost sites, and when and where bats are most vulnerable to disturbance. Biologists also can assess bat health and learn if the bat is infected with the fungus.

Biologists have other creative ways of studying these unique animals. Bats use echolocation to navigate and catch insect prey during the dark of night. People can’t hear these bat calls, but biologists use special microphones, called acoustic detectors, to record the sounds. By analyzing the bat calls, biologists can identify which specific bat species are present in an area during certain times of the year.
Bar chart showing Myotis bat species activity based on the number of recorded bat calls in the park both before and after white-nose syndrome's introduction.
Figure 1. Average number of calls per hour of bats of the genus Myotis in the park before and after white-nose syndrome’s (WNS) arrival in Vermont (2008). Data are from 2001 (3 sites) vs. 2010 (5 sites). Error bars represent +1 SEM.

In 2001 and 2010, acoustic detectors were used to measure bat activity levels in the park. In all, eight species of bats were identified. Many of these bats were of the genus Myotis—a group of bats that are generally sensitive to white nose syndrome. These include the federally threatened and state endangered northern long-eared bat (Myotis septentrionalis), the state endangered little brown bat (Myotis lucifugus), and the state endangered eastern small-footed bat (Myotis leibii). Biologists may have recorded a ninth species in 2010—the federally endangered Indiana bat (Myotis sodalis)—but they were not certain about the identification. Myotis species activity declined dramatically in the park following the introduction of white-nose syndrome (Figure 1, above).

What is the park doing to protect bats?

The data being collected on bats helps park managers conserve bats and their habitat. Protecting important areas where bats raise their young or hibernate for the winter and minimizing the loss of mature forests will help reduce the impacts of the disease. White-nose syndrome is an extraordinarily dangerous threat to bat populations—sadly, some species may ultimately disappear from the Northeast region.

Want to learn more?

For more information:

Contact National Park Service Ecologist Kyle Jones.

Last updated: September 21, 2018