The Smithsonian’s National Museum of Natural History has more than 140,000 bat species in its care, as bat population is declining due to several reasons. The institute’s website also encourages art lovers to explore artworks that have inspired many wildlife researchers in their study of bats. Additionally, the Smithsonian Conservation Biology Institute performs work in establishing measures for the security of bat populations threatened by white-nose syndrome, a fungal disease that has been affecting hibernating bats across the U.S. at an alarming rate.

A mid 1830s Japanese artwork entitled “Bats in Moonlight,” a painting by a Japanese artist named Utagawa Hiroshige (1797-1858) has inspired several researchers in their study of bat activities. The artwork was originally part of The Anne van Biema Collection, but is now in exhibit at the Arthur M. Sackler Gallery, Freer Gallery of Art.

Bat Species Suffer from Bad Rap as Evil Incarnates

Bats species of every kind suffer from negative misconceptions that they are generally blood suckers and disease carrying animals. The Smithsonian Institute aims to draw attention to the fact that over 1,300 species of bats are important to ecosystems. As part of the institute’s mission, its National Museum of Natural Arts endeavors to provide a key resource for research that bat conservationists and even bat removal experts can use in understanding how to best protect bats.

Modern day depictions of bats in moonlight are often associated with Hallow’s Eve, as a sure sign that ghouls and evil spirits are about to roam the Earth. Actually, several studies about bat’s nocturnal activities have been undertaken, all of which belie the belief that moonlight has uncanny effects on bat activities.

A Bat Research Unravels Information About Bat Activities During Moonlit Nights

A study conducted on bat activities during moonlit night was conducted by a certain Giulliana Appel, in connection with her Graduate Program in Ecology study with Brazil’s Instituto Nacional de Pesquisas da Amazônia (INPA). Ms. Appel collaborated with researchers from PPBio / CENBAM in the evaluation of the influence of the moon’s luminosity on the flying activities of insectivorous bats.

Ms. Appel’s research team had installed ultrasound recorders in the Adolpho Ducke Reserve, which they used in identifying bats and in evaluating their activity through the ultrasound that the animals emitted. In their study of five bat species, information gathered from a 53-day sampling revealed the following:

While moonlight intensity can affect bat’s flying activities, the opposite is true with aerial insectivorous bats, as they tend to lessen their flying activities during bright moonlit nights. The logical explanation for this is that bright nights tend to increase risks of predation; and that the availability of insects, foraged as food, likewise decreases for the same reason.

The researchers also concluded that lunar phobia does not apply to all bat species. Only one of the observed species, the Myotis riparius, had shown a negative response to moonlight.

It was observed that two species, the Saccopteryx leptura and the Pteronotus parnellii are inclined to increase their foraging activities during bright nights. This was mainly attributed to their high-flying capabilities.

On the other hand, two other bat species, the S. bilineata and the Cormura brevirostris did not show any signs that the level of their nocturnal activities are affected by moonlight intensity.