There’s Something Batty Going on

little brown bat
The little brown bat is found throughout Washington state. Photo: WDFW

There’s something batty going on with these little mammals. I mean, c’mon, they look like flying mice! The German word for bat is “Fledermous”, meaning “fluttering mouse.” Mammals can’t fly, can they?

Let’s ask Wikipedia:

“Bats are mammals of the order Chiroptera whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels … can only glide for short distances. Bats do not flap their entire forelimbs, as birds do, but instead flap their spread-out digits, which are very long and covered with a thin membrane or patagium.” Wikipedia, 2016

Bats are some of the most diverse and amazing animals in the world; in fact, they second most varied mammal group behind rodents. There are more than 1,300 species of bats in the world with the highest diversity in tropical realms such as Columbia and Indonesia. Yet bats occur in virtually all non-polar environments.

bat close up
Bats are the only mammals naturally capable of true and sustained flight. Photo: Teri Pieper

In Washington we have 15 species of bat, some of which migrate in the cold months to either hibernaculum sites (often suitable caves) or places where insects are available. Little brown bats have been found to migrate 200-800 km (125 to 500 miles) to hibernate. We actually know very little about bat migration.

Bats have a plethora of specialized behaviors besides flight, such as echolocation, hanging upside down, migration and hibernation.

Bats emit high frequency sounds that bounce off of their flying insect prey, (yes, it is radar), and this enables them to locate prey even in total darkness. They also use this amazing ability to fly in places full of obstacles and navigate in darkness. Toothed whales (like dolphins or sperm whales) also have this ability, and even a few tiny shrews.

Bats are scary looking, sort of, but really are just plain cute. No, our Washington species don’t eat blood. No, they don’t get in your hair. And, no, you won’t get rabies from them unless you happen to handle and get bitten by the rare individual carrying rabies. Bats are good to have around; really good.

Ecosystem Roles

As insectivores, bats are very important to the ecosystem. Bats help to keep in balance the many, many species of insects that can wreak havoc with our crops. Birds take the flying insectivore day shift while bats take over at night. A single little brown bat can eat its weight in flying insects in a single night. That’s a lot of mosquitoes that would have bitten us; it’s also a great many harmful agricultural pests that could have eaten our crops. No wonder that bats are considered “keystone” species in the environment.

Townsend’s big eared bat
A Townsend’s big eared bat near Mazama, Wash. Photo: Scott Fitkin

They fly about in those amazing tight maneuvers, catching insects in flight, often using their wings like ball gloves and deflecting the bug in close enough to their mouth to eat. If you ever find yourself at twilight in a place where you can watch bats flying, such as on a still lake in the summer, be sure to stop and marvel. They are amazing.

Nocturnal animals like bats need cover to hide in during the day. They roost and breed in the right season, in “just right” cracks, holes and crevices around the environment.  In nature, these are in rock (such as caves) and trees, particularly dead trees with access to places inside of the wood or under the bark. Hibernaculum sites are particularly sensitive and rare, with just the right combination of temperature and humidity.

Bat Populations at Risk

But bats are in trouble. Besides being sometimes reviled for reasons of superstition or wrong-headedness, there are big environmental troubles out there.

White Nose Syndrome has been decimating bat colonies in hibernation in the eastern United States. It is a fungus that can live in the cool, moist conditions where clustered bats congregate during hibernation. Their respiratory systems clog up and they die — by the millions. It is feared that up to 80 percent of eastern U.S. bats have perished in recent years. Unfortunately, a case of this disease was detected in Washington state just last year. Please contact the Washington Department of Fish and Wildlife if you find a sick or dead bat, or if you notice bats unable to fly. You can report your observations online.

It is also known that many thousands of bats are killed each year by collisions with wind turbine blades and/or rapid pressure change at turbines that can rupture blood vessels. (Bat Conservation International, 2016). As we transition to renewable energies, bats fatalities are apparently one unforeseen consequence of wind power. How this mortality will effect overall populations is unknown.

And habitat loss continues. Native forests, wetlands and prairies are converted to urban or suburban uses every day, completely erasing bat habitat. Standing dead trees with cavities and loose bark are routinely destroyed, removed for safety concerns, perceived aesthetics (dead trees are “ugly”) or for products such as fuel wood.

Landowners to the Rescue

Loose bark can provide bat roosts. Photo: Ken Bevis

What can we do to help bats? This is where our small forest landowners come in. The most important action is provide habitat that will give the bats in our environment the best chance to persist. Here are some steps you can take on your property:

Wildlife Trees: Bats rest under loose bark or in cavities and cracks of old trees. Stands of trees, especially larger diameter and dead trees, can provide critical habitat for bats to survive. We can help bats by keeping standing dead trees with loose bark, cracks and cavities on the landscape. The importance of dead trees as habitat cannot be overstated, especially those near forest openings and water.

Boxes: Many people want to help bats by building (or buying) a bat box. This is a simple thing you can do, but it must be properly constructed and located. Remember, a box is a mimic of loose bark or a tree cavity. Sometimes, it takes quite a while for bats to find boxes, so if they aren’t being used, move them. Bat Conservation International has volumes of information about bats and about bat box construction and placement, including plans for building a 4-chambered bat box.

Water Features: As small forest landowners your lands and trees can provide much critical habitat for bats, particularly in larger diameter, standing dead, or decadent, trees near water. Bats love to feed above small, still water bodies where insects are abundant and winds are gentle. Many small landowners have ponds, creeks or are near these water bodies. With trees, bats gain resting habitat close to feeding areas so they can keep working all night long.

Old sheds, cabins and shake roofs also provide bat habitat. In addition to building maintaining bat habitat structures, look around your property for existing structures, such an old shed, that could be prime real estate for bats.

If they get in your house, there are good ways to deal with that without resorting to killing them. Washington State Department of Fish and Wildlife’s Living with Wildlife series has good ideas for non-lethal removal of bats in your personal belfry.

Remember – bats are an amazing element of our Washington environment. Learn about them and help them by providing some habitat on your woodland.

For more information take a look at the Washington State Department of Fish and Wildlife’s Bat Conservation Plan

Visit the website of Bat Conservation International to find lots of interesting material.

Don’t’ forget, habitat is the key to wildlife.

The world needs bats.