Humans go batty on Halloween. People decorate with and dress up as the creatures of the night to create a spooky atmosphere. Their scary reputation is all wrong, said Teri Orr, a postdoctoral researcher in the School of Biological Sciences who studies bats.
PHOTO CREDIT: Dave Titensor, University of Utah
Teri Orr, postdoctoral researcher in the School of Biological Sciences, is interested in the reproductive strategies of different species of bats.
“I think the biggest thing about bats is that they’re so polarizing—people either love them and want to tell you everything they’ve ever known about bats, or they hate them and are terrified of them,” she said.
Orr is in the former camp. Along with research, she does outreach to raise awareness about the crucial role bats play in the environment, to dispel myths that make people fear them and to prove once and for all how dang cute they are.
Bats don’t vant to suck your blood
Some people hear “bat” and think of Dracula swishing a cape, morphing into a bat and flapping out of the castle moaning, “I vant to suck your blood.” Surprisingly, Hollywood got it wrong—bats aren’t vampires. There are species known as vampire bats that subsist on blood, but of the 1,200 to 2,000 species of bats, only three species drink blood that they usually get from other animals. The rest of our bat friends eat fruit, insects, nectar, fish, frogs or a combination of these.
“It’s interesting that we have this idea that bats are out for blood. I don’t know where it comes from. In movies where Dracula changes into a vampire bat may come from old European stories, but there aren’t even any real vampire bats there,” said Orr.
Vampire bats feed neighbors in need…but will hold a grudge
The “dreaded” vampire bats of South America are extremely social and take care of one another. After a night of foraging for blood, the bats will share their meal with a friend that returned to the roost hungry. They’re more likely to do so if they’re closely related. However, they expect to have their favor returned, Orr said.
“Vampire bats are definitely Tit for Tat. If someone needs blood, they’ll share it. The way that they do that is really gross—they regurgitate it into their mouths. The next time they’re hungry, they expect to get blood from that same neighbor. If he doesn’t return the favor, they won’t share with him again,” said Orr.
Like tequila? Chocolate? Thank a bat
Bats pollinate over 500 species of plants. Just like bees, bat species fly from flower to flower, looking for nectar and inadvertently delivering pollen from one plant to another. Mangos, bananas, cocoa and agave plants are all pollinated by bats.
Lady bats can store sperm, delay pregnancy and suspend animation
Orr’s specialty is in bat reproduction. Who can blame her—it’s fascinating. Various bats species can delay reproduction at different stages of development. One of the most common is storing sperm. Certain species of bat can meet, mate, and then store the sperm for later, Orr said. In Utah and throughout other parts of North America, some bats mate in the fall or in the winter, but the sperm doesn’t fertilize the egg until the spring. Sometimes, they store the sperm for up to 200 days. Other bat species delay when the fertilized egg implants into the uterus. For her doctoral dissertation, Orr studied the rarest form of delays.
“A female allows fertilization to happen, then implantation happens, and then right when the placenta begins to form, there’s a pause, sort of like suspended animation,” Orr said. “What’s cool about it is that there’s no cell growth at all. The species that I studied do that for a couple months which is pretty impressive. People often tell me, ‘I was pregnant, and that would have been nice.’”
Bats share the best fruit spots
If a bat finds an especially juicy fruit spot, they’ll share the information with their batty friends.
“Studies on species that find fruit have shown that they go back and say, ‘Hey! I got some fruit over here,’ How they’re communicating that information is less known, but it’s very clear that if a bat is prevented from going back to the cave, it takes their roost mates longer to find the spot.”
Guano for fertilizer and gunpowder
Bat poop has been used as a fertilizer for hundreds of years. Until World War I, soldiers harvested bat guano for gunpowder and explosives.
Bats species share caves
Bats are really good neighbors. Orr studied a cave in Mexico where 15 different bat species shared the space.
“Each species were in separate parts of the cave, depending on their preference—some bats like to roost in the Twilight Zone near the front of the cave, and others need to be a way back in the dark areas. So they spatially segregate the cave so that everybody’s kind of happy in the preferred habitat and they peacefully get along with other species.”
Not everyone is afraid of bats
Bat festival, anyone? Bats are a symbol of good luck in Chinese culture so every year a bat festival is held. Also, a gift with a bat image will bring the recipient prosperity. Mexican culture has a bat god depicted in Anasazi pottery carvings.
Losing bats will cost farmers billions
This fact is a bit spooky. Insectivorous bats eat tons of insects, helping keep agricultural pests under control. However, North American bat populations are declining due to two major threats: an infectious disease caused by fungus that causes symptoms termed “white-nose syndrome” has nearly wiped out bats in the northeastern United States, and scientists have estimated that wind turbines in the southwest may kill tens of thousands of bats every year. The loss will affect American farmers—one study calculated that the bats’ insect service are worth roughly $23 billion per year.
*Banner photo credit of Eptesicus fuscus, big brown bat: Brock Fenton