The Bat Project

Solving Vienna's mosquito mania since 2021

Much ado about mosquitoes

We've all been there- it's finally summer time, so we go and fire up the grill or go off to camp and while we come back with tons of memories to be cherished, we also return with something a little less nice- big, red, itchy, mosquito bites. The pesky pests seem to be almost invincible- no amount of bug spray will completely protect you. It's crazy to think that this is the least amount of damage they can do as well- some mosquito bite victims contract West Nile virus, Zika virus, and malaria, which depending on the severity can be lethal. And here's the worst part. Because of the rapidly rising temperatures, mosquitoes don't get killed off completely in the winter and the larvae are able to grow and emerge earlier fully grown and ready to bite. This means their populations are just going to get bigger and bigger, and mosquito-related problems are going to get worse and worse. Scary, right? Never fear, Vienna, for there is a natural, native solution: bats!

Bats to the rescue

Now, when most of us think of bats, we think of either the infamous superhero, or we think of pesky little critters that like to hide in our attics. However, there is much more to bats than meets the eye. Speaking of eyes, ever heard the expression 'blind as a bat?' It's not necessarily true. Yes, the nocturnal creatures have horrible eyesight but they make up for it with a unique hunting and navigational strategy known as echolocation. This technique is used by thousands of species of bats, as well as all toothed whales and a few small mammal species. Echolocation is where the animal emits a sound or frequency (in bats cases, the frequency is extremely high and barely perceptible to the human ear) and listens for the echo of the sound waves bouncing off of an obstacle or prey in their path of travel. In simpler terms, echolocation is nature's radar!

A bat uses the echo of sound waves to identify its prey, much like a boat uses radar to scan the bottom of a body of water to find abnormalities.

An adult, silver haired bat on a Virginia pine tree.
Source: Silver-haired-bat,, 2009

An adult Little Brown bat in a cave in Virginia.
Source: Little brown bat,, 2018

An adult Big Brown bat hunting its prey in Virginia.
Source: Big brown bat,

A batty banquet

Now that we've learned how bats get to their food, let's learn a little about what bat food is. Different bat species around the world have adapted diets specific to their environment. Bats in Australia, for instance, eat mainly fruit as that is a plentiful resource steadily available throughout the year. Bats in the forests of Panama eat small rodents and insects, as there is less competition for rodents than there is for fruit in that ecosystem. Bats here in the U.S. are all mainly insectivores, though, meaning they eat all sorts of bugs. Now, specifically here in Vienna, we have 3 main species of bats- the Big brown bat, the Small brown bat, and the Silver-haired bat- all of which are insectivores that specialize in devouring our favorite pesky pests: mosquitoes! Bats have an extremely high metabolism and rely on the high protein contents of insects like mosquitoes and moths to keep their body temperature up, their energy up, and their internal organs functioning. Mosquitoes, though, are rather small and do not provide a lot of minerals individually, so one bat can eat up to 2,000 mosquitoes a night!

(Bat)Housing Crisis

You may be thinking, 'Okay, but what's the whole point? All you've done is outlined a basic environmental food chain principle.' To that I say, patience! While we have some bats here in Vienna, our populations are still unstable and a quarter of all bat species in Virginia are on the federal endangered species list. The problem is not food scarcity, as we have plenty to share. So, what is the issue? Habitat. Bats native to Virginia roost in between the bark and trunk of loose-barked trees or dead trees. However, dead trees are a fall risk so we usually remove them as soon as possible. There is a solution, and it's simpler than you might think.

A long eared bat roosts in between the trunk and bark of an oak tree.
Source: Northern long-eared bat,

Dr. Charles Campbell and his 30 -foot tall bat hotel.
Source: Merlin D. Tuttle,

A modern day bat house
Source: Untitled, gardeningknowhow,com

To the Bat-Cave? No, the Bat-House!

In the early 1900s, bacteriologist Dr. Charles Campbell of San Antonio was tasked with trying to solve the malaria crisis going on in the southern U.S. and Mexico. He knew from his research that bats local to the area feasted on mosquitoes, and built the first bat house. His first attempts were humorous, yet unsuccessful. (For the full story, click here )After 2 years of studying caves and other bat houses, he finally settled on a smaller, more compact design to mimic the coziness of a belltower roost. While the building style and shape have changed over the years, Dr. Campbell is credited as the father of the bat house and is known internationally for his studies in the spread of malaria and using natural resources to combat the mosquitoes that carry it. Today, bat houses are an affordable, safe way to encourage bats to roost in a given area.

Tying it all together

The Bat Project aims to encourage bat populations to roost in Vienna in order to control our mosquito crisis by installing 2 bat houses in Southside Park. Each bat house can support a colony of 50 mature adults, or 75 young adults. Now, while this will help, this is not a full solution. We can't change much with 100 bats. So we are calling on you! You fellow Vienna residents can help turn the tables on our mosquito crisis with these few easy steps.

  1. Clear all stagnant water.

Mosquitoes lay clutches of eggs in stagnant, still water. This means empty flower pots, buckets, bird baths, or even dog bowls left outside. Be sure to overturn anything that can collect water before a storm, or if you know you won't be able to monitor it or use it within the next few days. Dog bowls left outside should be cleaned regularly and overturned when not in use as to prevent the development of a breeding ground.

2. Pick up your litter

Plastic grocery bags, single use water bottles, and aluminum cans are optimal breeding grounds for mosquitoes, as they collect just enough water for them to lay a clutch of eggs and their predators won't go searching for them there. It's for the environments good and for your good. Please, just pick up your trash. It's that simple.

3. Take care of your yards

Once past nymph stage, young mosquitoes live in tall grasses and dense brush. Keeping your lawn mowed and brush tamed will help reduce mosquito issues as well as provide some nice curb appeal. Don't feel like doing it yourself? There are plenty of fantastic landscaping companies throughout Vienna that are happy to help! For more information, click here .

4. Install your own bat house!

Whether you order a premade house or you want to go the full 9 yards and make one from scratch, there are plenty of fun and hassle-free options to make your yard a safe haven for our local bats! For instructions on how to build your own, where to install it, and more helpful hints, click here.