By Isabella Diehl
The Indiana bat is listed as an endangered species under the Endangered Species Act of 1973. It is important that we work on their conservation as the population continues to diminish. These bats are crucial parts of the ecosystem and provide many benefits to the earth and humans as well.
Indiana bats are brown or black and are only 2.9 to 3.9 inches long, with wingspans of 9.5 to 10.5 inches. They are found in forested environments in the eastern United States, including Wayne County, Ohio. These bats hibernate in the winter, when 72% of the species population comes together to hibernate in just four sites in Missouri, Indiana and Illinois.
They hibernate in clusters underground in sites such as caves or abandoned mines. These clusters can contain thousands of bats, and the large number of bats helps keep the temperature stable even if the outside temperature fluctuates suddenly. It also helps to muffle sounds that could disturb the bats. In the summer, the females live in maternity colonies (which can house up to 100 bats!) in roost sites that are often under the loose bark of trees. This communal roosting helps to keep the temperature ideal for pregnancy.
In midsummer, the bats give birth to a single pup, who is dependent on the mother for about a month until it can fly and feed on its own. The females return to the same maternity colony every year. Male bats roost in similar environments, but they do so by themselves or with a much smaller colony. In the fall, bats arrive at the hibernation site to mate at the entrances of the caves or mines. The females have delayed fertilization, which means that ovulation does not occur until months later in spring.
Indiana bats are nocturnal insectivores. They feed after sunset and capture and eat many types of flying insects, using echolocation to hunt by producing sound waves which bounce off objects in their environment and return to the bat’s ear. They also eat ants, spiders and mites, showing that they can be opportunistic. Over the course of a night, they can eat up to half their body weight in food.
In general, bats are important to the ecosystem because they eat insects, helping to lower the population of crop pests. In the United States, bats save farmers at least $3.7 million in pest control every year. They are also pollinators and seed-dispersers, helping maintain the biodiversity of the environments they live in. Additionally, they benefit the cave ecosystems that they live in because their droppings, called guano, are an important nutrient source for many cave-dwelling organisms.
Human disturbances are the main reason that the Indiana bat is endangered. These bats hibernate in large groups in a very small number of caves, so they are extremely vulnerable. If they are awoken by humans in the winter, they lose a part of their energy supply that is essential for survival.
Additionally, a disease called white-nose syndrome has greatly harmed the Indiana bat population. It is caused by a fungus that grows in cold, damp places, such as caves. It grows on the skin of the bats while they are hibernating and can cause dehydration, starvation and death. This disease affects many species of bats and has wiped out over 6.7 million of them in the United States. Finally, with the increased use of pesticides, many of the insects that these bats hunt and consume are contaminated with poisonous chemicals, which can cause a bat serious harm with repeated ingestion.
Fortunately, many efforts are being made to conserve the Indiana bat species. Caves are being protected because of the crucial role they play in the bat’s habitat and the fact that human activity in caves can be a huge disturbance for bats. To that end, the Ohio Revised Code 1517 includes a Cave Protection Act to help preserve cave life and material.
It is also essential that we protect these bats’ summer habitats. Female Indiana bats require large trees to give birth and rear their pups, but habitat loss has decreased the number of places that they can roost. Another important part of conservation is education. Many people do not realize how important bats are to our ecosystems and how they directly benefit humans, so outreach initiatives are crucial in educating the public about the ecological importance of the Indiana bat and informing the public about current preservation efforts that they can support.