How can anyone in Idaho think that bats are scary?
Despite what you see in the movies, these fascinating flying mammals wouldn’t hurt a fly! Well, technically, they would hurt a fly, or a mosquito, or a moth. But other than that, bats are harmless. 🙂
Did you know there are 14 kinds of bats in Idaho?
It’s hard to believe the diversity and amount of species that can be found in Idaho! But, unfortunately, when you see a bat, it’s typically pretty difficult to determine which kind of bat it is. These nocturnal creatures fly incredibly fast and are only active at night.
#1. Big Brown Bat
- Eptesicus fuscus
- Larger-sized bat with around a 12-inch wingspan.
- Brown fur with black ears, wings, and feet. Wings are hairless.
Big Brown Bats are widespread all over Idaho.
If you look, you’ll find these bats inside caves, tunnels, or other human structures.
Big Brown Bat Range Map
This nocturnal bat primarily eats insects, especially ones that fly at night. However, their preference is to eat beetles.
The Cucumber Beetle is their favorite, which benefits farmers because these insects are terrible pests for agriculture. Many farmers in Idaho even use bat boxes to attract Big Brown Bats to their property!
Though rabies is common in all bats, research has shown the disease is rarer in this species.
The reason for this fact is that many Big Brown Bats have immunity to rabies. Interestingly, researchers discovered that these rabies antibodies get passed down from generation to generation!
#2. Hoary Bat
- Lasiurus cinereus
- Brown hair with grayish-white tips. Wings and belly are brown and hairless, with a wingspan approximately 15.5 inches.
- Males are almost double the size of females.
You’ll typically find Hoary Bats roosting on trees in woodland forests. But occasionally, they will go into caves to stay with other bats.
Hoary Bat Range Map
This species prefers to hunt for prey while flying over wide-open areas or lakes. Hoary Bats hunt alone and enjoy eating moths. They’re known to travel up to 24 miles in a single night to gather food!
Though the Hoary Bat is not endangered, it does suffer a loss in numbers because of wind turbines. Hoarys’ migrate each year back and forth from North America to Central America, and it’s thought that they confuse the wind turbine with being a tree as they seek a place to rest. As you can imagine, these bats meet a horrible death.
#3. Silver-haired Bat
- Lasionycteris noctivagans
- Medium-sized bat, flathead, and the upper part of the tail are covered in thick fur.
- Mostly black all over with white tips on hairs, with a wingspan that is approximately 11.5 inches.
The Silver-haired Bat is known to fly more slowly than other bats in Idaho.
Look for Silver-haired Bats in forests inside tree cavities or bark crevices. They’ve also been known to seek shelter in outbuildings.
Silver-haired Bat Range Map
Silver-haired Bats hunt for soft-bodied insects, such as moths. Interestingly, they also eat a lot of spiders. They accomplish this feat by foraging low to the ground to find food, unlike many other bats.
Unfortunately, rabies occurs more often in this species when compared to other bats.
#4. Little Brown Bat
- Myotis lucifugus
- Glossy brown fur on the body. Wings are hairless and black with a wingspan that is approximately 9 to 11 inches.
- Despite its name, it has no connection to the Big Brown Bat.
The Little Brown Bat is common and lives throughout Idaho.
Look for them in sheltered places such as human structures, woodpiles, tree hollows, and occasionally caves.
Little Brown Bat Range Map
Little Brown Bats will commonly use a bat house for roosting. Many people put up bat houses to attract them to their property to control pests like mosquitos or insects that harm crops.
Little Brown Bats only have a few natural predators, like owls or raccoons. Unfortunately, most of their mortality is caused by parasites or White-nose syndrome.
White-nose Syndrome is a fungal disease that grows around the bats’ mouths, ears, and wings. This illness is spread during hibernation and is responsible for the loss of over one million Little Brown Bats between 2006 and 2011. As of 2018, the Little Brown Bat is an endangered species.
#5. Townsend’s Big-eared Bat
- Corynorhinus townsendii
- Medium-sized bat with extraordinarily long and thin ears. Lumps on each side of the nose.
- Dense fur all over, colors vary from grayish brown to brown. Their wingspan is approximately 12 to 13 inches.
It’s pretty easy to see how these bats got their name! Their large ears are essential, as they help them distinguish between ambient noise and sounds of prey or predators.
Townsend’s Big-eared Bat Range Map
During summer, males and females inhabit different roosting sites. Males live alone, while females form colonies where they raise their pups.
This species is known as a “whisper bat” because it echolocates much lower than other bats. This comes in handy when foraging on moths because moths can hear bats’ echolocation. So, as you can see, being quieter gives Townsend’s Big-eared Bat an advantage.
#6. Western Small-footed Myotis
- Myotis ciliolabrum
- Smaller bat, with yellowish-brown fur and sometimes white underparts.
- The muzzle, chin, and ears are black. Ears are also long. Their wingspan is approximately 8 to 10 inches.
- Feet are tiny, just as their name suggests.
The Western Small-footed Bat is found in semi-arid habitats in Idaho.
Though this bat is a slower flyer, it can maneuver well. The Western Small-footed Bat tends to feed close to the water, searching for insects like beetles, moths, and flies.
Western Small-footed Bat Range Map
Western Small-footed Bat females roost in groups, and males roost alone, but both hibernate in winter in solitude.
#7. Long-legged Bat
- Myotis Volans
- Fur color can vary from light or dark brown to reddish-brown. Tips of ears touch the side of their nose. Wingspan is approximately 10 to 12 inches.
- Unlike other bats, they have fur on the underside of their wings from their elbows to their knees.
- They got their name from having a longer tibia bone when compared to other bats.
The Long-legged Bat has unique feet that allow them to hang upside down for an extended time and not waste any energy. This feat is accomplished by locking their toes in place. In addition, special cavities in their head prevent blood from going to their brain.
Long-legged Bat Range Map
These bats prefer to roost in barks of trees, crevices in rocks, caves, and even buildings. They like to spend time in higher elevations in summer and then in winter will come down and live and hibernate in caves and mines.
Like other bats in Idaho, they primarily eat mainly moths using echolocation. However, the Long-legged Bat differs because they get a head start over other bats! They do this by leaving their roost early, foraging before sunset, and then eating throughout the entire night.
Check out this video to see how the Long-legged Bat uses echolocation to catch moths!
#8. Yuma Myotis
- Myotis yumanensis
- Smaller bat, fur varying from dark brown to grayish. Underside fur is dull and pale. Wingspan is approximately 9.4 inches.
- Feet are large and wide, ears long straight and thin, short head and broad snout.
These bats are found in many different lowland habitats in Idaho, including coniferous forests and dry scrub forests. However, they are typically always near water.
Yuma Bat Range Map
You will often see them in huge groups in caves, buildings, mines, or other structures.
The Yuma bat is an opportunistic hunter and is not picky about what it eats. They will consume whatever is most abundant in that area, such as beetles and other soft-bodied insects. Look for them flying over slow-moving water or by vegetation as they forage for insects.
Interestingly, these bats will sometimes use their tail membranes as a pouch to catch larger insect prey.
#9. Long-eared Myotis
- Myotis evotis
- Face and ears are black. The fur on their back ranges from yellowish to dark brown. The wingspan is approximately 9 to 10 inches.
- Long dark ears, which is how they got their name.
The Long-eared Myotis is found in woodlands, shrublands, grasslands, and agricultural areas. This species leaves its roosts in rocky regions, dead trees, caverns, and buildings to forage insects in dense vegetation.
Long-eared Myotis Range Map
The Long-eared Myotis is active longer at night than other bats in Idaho, hunting closer to the ground as the night gets cooler.
Unlike other bats in Idaho, the Long-eared Myotis often turn off echolocation when hunting. Instead, their long ears help them HEAR prey the old-fashioned way. Click play below to see an example!
#10. Fringed Myotis
- Myotis thysanodes
- Smaller bat with long ears and a tiny face. The wingspan is approximately 10.4 to 11.8 inches.
- Light yellowish-brown or dark greenish fur and back and off-white on the underside, brownish-black ears, wings, and legs.
In Idaho, you’ll find the Fringed Myotis in desert shrublands, sagebrush grasslands, and woodland habitats with pine and oak trees.
Fringed Myotis Range Map
These bats have a diet that consists primarily of beetles.
The Fringed Myotis has a fringe of short, wire-like hairs on the membrane between its hind legs, which is how it got its name. It has been thought that these hairs help it catch insects while flying.
The Fringed Myotis echolocation is different from other bats. They start by flying in a downward swoop and then begin to search for food.
#11. Pallid Bat
- Antrozous pallidus
- Larger bat with long, super thin, forward-pointing ears. The wingspan is approximately 15 to 16 inches.
- Tiny face with a pig-like snout.
- Fur is brown and creamy white by the root on their back, and cream color on the underside.
The Pallid Bat is the most unique-looking in Idaho!
I just love its unique, pig-like nose! Look for them in habitats that consist of deserts, grasslands, canyons, and mixed forests.
Pallid Bat Range Map
Pallid Bats eat various foods, including both ground and flying insects, nectar, and scorpions. They like a balanced diet with their food buzzing, sweet, and spicy.
This loud bat is known to bare its teeth and buzz when frightened or angered.
#12. Spotted Bat
- Euderma maculatum
- Fur on the back is black with three distinct white spots. The underbelly is white.
- Tiny gray face with HUGE pinkish ears. The wingspan is approximately 14 inches.
The Spotted Bat has the most oversized ears of any bat in Idaho!
Spotted Bat ears are unique because their ears roll up around their head when they’re resting. And then, when they become active, the ears fill up with blood and unroll.
Spotted Bat Range Map
Some Spotted Bats hibernate in cold weather, which means their heart rate slows down, and their body temperature falls to their surroundings. Other individuals will migrate to warmer weather.
Spotted Bats are very territorial and prefer to live in solitude.
This bat is one of only a few bats with an echolocation sound that is low enough to be heard by humans!
#13. California Myotis
- Myotis californicus
- Smaller bat with brown fur and black ears, wings, legs, and feet.
- Sloping forehead and a short tail that does not extend past the membrane.
Look for the California Myotis in lower elevations and forested habitats. They roost in rock crevices, dead or hollowed trees, under loose bark, and buildings in the summer. In winter, you’ll find them in caves or mines.
California Myotis Range Map
The females and males roost in separate places during the summer but then reunite during hibernation.
The California Myotis flies slower and more erratic as it hunts near the edges of the forest or over water.
#14. Canyon Bat
- Parastrellus Hesperus
- Smaller bat. Fur color can vary from golden brown to reddish-brown.
- Face, wings, ears, and legs are black. The wingspan is approximately 7 to 9 inches.
The Canyon Bat is one of the most common bats in Idaho.
This species is mainly found in rocky areas near water, like canyons, cliffs, under loose rocks and caves.
Canyon Bat Range Map
Since this bat is small, its most common predators are owls. But, unfortunately, these little guys also sometimes have to worry about predation from other larger bat species.
Interestingly, the Canyon Bat has been known to occupy rodent burrows in the ground if their habitat doesn’t provide them with sufficient shelter.
Do you need additional help identifying bats in Idaho?
If so, this field guide should be able to help you.
Which of these bats have you seen before in Idaho?
Leave a comment below!