Bats of Wisconsin

They are not often seen or heard, but Wisconsin bats are fluttering through the warm summer skies, playing an important role in our ecosystem. In Wisconsin, we have nine recorded bat species, all of which are insectivores, meaning they only eat insects.

A single little brown bat can eat approximately 1,000 mosquitoes and other small flying insects in one hour. The largest bat species, the hoary bat, will eat larger insects such as moths, beetles, and even wasps. Because of the amount these bats consume and how small they are, their role within their habitat is to be a predator to those insects as well as prey for animals like snakes, owls, and even raccoons.

Bats create a bridge for the energy to flow in the ecosystem. Looking at a simplified food chain, the base are the plants, which get eaten by insects. Those insects are eaten by bats, which then are eaten by their predators. If bats are removed from this food chain, the top predators wouldn’t be able to survive, as these predators are unable to eat enough of the insects to satisfy their appetites. Those uneaten insects would eat too many plants, damaging the plant populations. Of course, the ecosystem is much more complicated due to the number of other living and non-living things, but even the removal of one factor can affect the whole system.

Here at the Center, we actively restore and manage the variety of habitats around the property, from planting native

Wisconsin flora, to digging new ponds, and even leaving dead trees. Indirectly these projects have helped bat populations by providing food, water, and shelter. From June to mid-July, we participate in Acoustic Bat Monitoring with the Wisconsin DNR. The data that is collected helps to inform our conservation team where bats are most active. Through this monitoring project, the 2015 Bio Blitz, and chance encounters, we have documented six of the nine bat species on our property.

To enjoy these flying mammals at home and reap the benefits of natural pest control, there are things that you can do in your backyard to create a welcoming environment. One of the simplest things that can be done is to plant native Wisconsin plants, including species that have their flowers open at night. These plants attract insects, which creates a buffet for the bats. In addition, eliminating the use of pesticides makes sure to not kill their food source. Another simple thing that can be done in your yard is to provide shelter. Planting native trees, and leaving dead trees, can provide a natural shelter among the leaves or under the bark. If that’s not feasible, bat boxes can be put on buildings or on tall poles.

By doing a number of these small actions, we can make a large impact to encourage bats to make appearances in our yards and help to keep a balance to Wisconsin ecosystems.