Bats are some of the most populous animals on the planet, and they live on every continent except the arctics. They’ve also been around for a very, very long time, dating back as far as 52 million years ago. For as pervasive and long-lived as bats are, it makes sense to ask the question, “What do bats eat?”.
In this article, we’ll be answering this question by examining the dietary preferences of some of the most common bats while also revealing some interesting facts about this fascinating animal.
Photo Credit: Daniel Speiss on Flickr
In a Word: Insects
When we take stock of all of the bat species on the planet, we arrive at a total number that well exceeds 1,200. With that many different kinds of bats, you might think it would be difficult to determine what their most commonly preferred food is.
Thankfully, biologists have been studying bats for a long time, and they’ve concluded that the most desirable food for most bats are insects. But, not just any old insect will do. You see, insectivore bats aren’t interested in crawling around on the ground on the hunt for things like beetles or centipedes. Instead, bats take to the skies to snatch flying insects out of mid-air.
This means mosquitos, gnats, and flies make up the vast majority of the diet plan for most bats. But, it’s important to note that some bat species don’t eat insects at all. In fact, the famous Vampire Bat prefers to lap up the fresh blood of their hosts, often while the host is sleeping and completely unaware of the bats presence whatsoever.
Alternatively, many bats prefer to dine on fruit or the nectar of some flowering cactus plants that grow in arid environments. These types of bats are known as frugivores, and some of them happen to be the largest bats on the planet.
[Fun Fact: Whether it’s insects, fresh blood, fruit, or cactus nectar, bats play a critically important role in regulating entire insect populations and ensuring the seasonal pollination of many kinds of flowering plants.]
Bat Diet FAQ
To add some color to the subject of what bats eat, let’s consider the following commonly asked questions on the subject.
How many mosquitoes does a bat eat?
This is a frequent question, because the answer is often used to bolster the perceived value that bats have among our ecosystem. If bats eat a lot of mosquitos, then bats are easier to live with, right? A study conducted in 1960 revealed that when hungry bats are released into a confined area packed with mosquitos, they can eat roughly 10 mosquitoes per minute.
If we extrapolate that data throughout the course of a given night of hunting, it’s not unreasonable to presume that a single bat could eat north of 1,000 mosquitoes a day. But, there’s a problem with this reasoning, and it has to do with access to available insect prey.
You see, when the 1960 study cited above was conducted, the bats in question where only presented with the option of eating mosquitoes. If you released a famished person into a room full of nothing but french fries, you would probably be impressed by how many french fries that person could eat. The same corollary can be drawn with that study.
More recent research suggests that mosquitoes only make up a small portion of insectivorian bat diets. Other flying insects like mayflies, moths, and katydids comprise a much larger portion of wild bat diets.
Do bats eat wasps?
If bats aren’t eating as many mosquitoes as we initially thought, what about wasps? The answer is yes, bats will eat wasps if the opportunity presents itself. In fact, some bats are the only flying predator of certain adult male wasps, whereas other animals like badgers, skunks, and raccoons are more interested in raiding wasp nests for the tasty larvae that is growing inside.
What makes wasps a challenging meal for bats doesn’t have to do with their stinging capability. Rather, it’s their window of activity that presents the problem for bats. Bees and wasps do most of their flying during the day, and they’re not nearly as active at night, which, as we know, is when bats come out to hunt.
Do bats eat ticks?
Generally speaking, bats do not eat ticks. Why? The answer is actually quite simple: ticks do not fly. As we’ve learned, most bats prefer to hunt prey that is flying through the air—bats use their highly sensitive echolocation abilities to locate swarms of insects and then dive into them for their meal.
Interestingly, when it comes to bats vs. ticks, a converse phenomenon is observed in nature. That is to say, some ticks will actually feast on bat blood. One tick species in particular—known as a ‘soft tick’—actively seeks out bats in their roosts, where the tick will climb onto the bat, inject it’s feeding mouthparts, and consume bat blood until it is fully satiated.
What should I feed an injured bat?
If you ever come across a grounded bat, know that certain steps should be taken to protect both you and the bat in question.
Do not handle a bat without wearing protective gloves. While most bats are not rabid per se, they can be, and they can also carry other contagious diseases that may affect humans.
Document where you found the grounded bat and under what conditions. This will be important for local animal control.
If possible, relocate the wounded bat to a warm area. Bats need to be warmed up before they eat, and if the bat is cold, it’s likely that it will starve before anything else.
Mealworms or chunky cat food can be used as a food substitute until help can be administered to the injured bat.
Remember that some bat species are highly endangered, and their livelihood depends on humans treating their habitats with respect.
How many insects do bats eat?
We’ve looked at how many mosquitoes bats eat, but what about insects on the whole? This question is a bit more difficult to answer, as bats vary so much in their size and appetites.
But, to illustrate just how voracious some bats can be, it might be helpful to look at one species in particular: the Grey Bat that lives in the Sylamore District Cave in Arkansas. This hungry little fellow can eat more than its weight in insects throughout the course of a single feeding session, and the 250,000-large colony of Grey Bats that inhabit this cave are responsible for consuming 150 billion insects in a single season. That’s a lot of bugs!
Do bats eat flies?
Yes. Bats will eat flies, but they prefer larger bugs with more ‘meat’ on them.
What do bats eat in the winter?
The answer to this question depends on where the bat is, geographically. Bats in tropical climates may not have to worry about food scarcity, whereas many bats in other parts of the world need to hibernate in order to make it through the winter.
So, during the winter, bats eat whatever they normally would during any other time of the year—mosquitoes, katydids, etc. That is, if they’re not hibernating instead. During hibernation, bats enter a state of ‘torpor’, which is a slowed-down biological status that nearly eliminates their need for food at all.
What do bumblebee bats eat?
These western Thailand-based bats dine strictly on insects.
Do bats eat rats?
It is very rare, but it has been shown that some bats will eat small rodents like mice and rats. These bats are exceptions to the rule, however, as most grounded rodents are difficult for most bats to prey upon.
Here is fascinating footage of a “False Vampire Bat” making a meal out of a small mouse.
How many bugs do bats eat a night?
Bats that prefer an insect-based diet can eat upwards of their entire body weight in bugs throughout the course of a single hunting session. Depending on the size of the bugs consumed, the total number of devoured insects could range between a few dozen to a thousand or more.
Do Fruit Bats eat insects?
Fruit Bats will consume insects in two ways: either by eating insect-infested fruit, or by simply eating insects as they come upon them. However, these bats are primarily frugivores, and nectavores and insects only make up a small portion of their diet.
What do Gray Bats eat?
The Gray Bat chooses to eat insects that fly above lakes, ponds, and other bodies of water. These insects largely consist of Mayflies.
Flies. Mosquitos. Flying beetles. Katydids. These as well as other flying insects are the food-of-choice for roughly two-thirds of all of the bat species that inhabit the planet. However, frugivore bats like the Fruit Bat prefer to eat fruit or nectar, while the all-hallowed Vampire Bat has a marked preference for blood.
We hope you’ve learned a thing or two about the common bat diet. If you’re hungry for more information on bats, feel free to explore the other resources listed on this page.