Why is the park interested in bats?
Bats are an important part of ecosystems and food webs. Though some species of bats feed on fruit, seeds, or pollen, the species that live in Virginia 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, biologists are studying how local bat populations are changing.
- Recent monitoring (2016-2017) detected 11 species of bats in the park, including two federally threatened or endangered species.
- White-nose syndrome has negatively affected several of these species.
- Bat activity is highest near the Fredericksburg Battlefield, primarily due to high activity of urban-adapted bats (i.e. big brown bats).
How do biologists study bats? What have they learned about bats in the park?Biologists have 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, so 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.
From 2016-2017, scientists used acoustic detectors to document 11 species of bats in the park (see Figure 1 below). The most commonly detected bat species was the big brown bat (Eptesicus fuscus). Interestingly, bat activity was highest in the most urbanized area of the park (Fredericksburg Battlefield). In this area, big brown bats are likely abundant. Big brown bats can easily adapt to urban areas and are less impacted by white-nose syndrome than other bats.
Researchers are also capturing bats and using radio-tracking devices to follow bats to important habitats. Park managers can then better protect these areas. For example, several species of bats prefer mature forests as feeding areas. Mature forests are rare in the Fredericksburg area, suggesting that the older forests that remain are likely serving as critical bat habitat.