Bats of Idaho

By Sarah Cubells

For good reason, the birds and large mammals of the Greater Yellowstone Ecosystem are the awe-inspiring “main characters” among locals and tourists alike. But, outside of Halloween time, I don’t hear much about the fascinating 14 bat species found in Idaho. I do find myself appreciating them as we head into summertime—My skin is covered in mosquito bites currently, and all of Idaho’s bats are insect-eaters (insectivores).

Bats reproduce slowly, which is unusual for small mammals. Female bats possess the amazing and unique ability to actually delay egg implantation (fertilization) in response to environmental factors such as food availability. In temperate climates, bats generally mate in the fall and then delay egg fertilization until they come out of hibernation in the spring! Each birth, which typically takes place around mid-June in Idaho, usually results in a single pup—yes, bat babies are called “pups”—although it is possible for them to have twins. 12 of the 14 bat species in Idaho hibernate, while the other two species actually migrate south for the winter.

Bats are the only mammals capable of continuous, flapping flight. A few bat species found locally, including long-eared myotis, pallid bat, and Townsend’s big-eared bat, can collect insects off of vegetation, and have unique wing shapes allowing them to hover and carry larger prey according to the Yellowstone National Park Service.

Bat soaring over water
A bat spreads its wings and glides over a body of water

Bats use an “echolocation system” to orient and find food in the dark. This means they use their physical features and sonar (Sound Navigation and Ranging) to navigate. Many bats use high-frequency calls, which help them detect prey while avoiding detection by predators. Although many of us are familiar with the expression “blind as a bat,” bats also generally have excellent vision, some even better than humans.

Bats can rest upside down for months! Their heads contain cavities that allow blood and other fluids to pool separately from the brain.

There are several common misconceptions about bats. According to Idaho Fish and Game (IDFG), a bat flying in the daytime does not necessarily constitute a risk to human safety. Bats occasionally fly in the daytime, especially when the migratory species are on the move. Another common misconception, according to IDFG, is that bats “attack” people. Bats are generally gentle by nature and do not attack people. They will act defensively when people attempt to pick them up, so make sure to steer clear of attempting to handle them!