Bats often maligned, but offer much
Due to their unique and unfamiliar appearance, bats have been cast by humans as frightening and ugly.
Their nocturnal habits have automatically associated them as dark and evil. Bats can also thank the Romanian legend of Dracula, where a man turns into a bloodthirsty vampire bat at night and flies about pursuing victims. This tale created their ridiculous and completely false impression.
Fear and habitat destruction by human beings has led to the onslaught of these creatures. Moreover, environmental factors, such as the widespread of several diseases, have left the bat populations dwindling in numbers. Even certain bat species that were once flourishing have recently found themselves on the endangered list.
|Click on the video at the right to view an audio slideshow about bats in national parks narrated and prepared by writer Jordana Levinson.|
Bats account for 20 percent of all mammals in the world with more than 1,000 various species. There are 45 different species of bats in the United States alone.
Many of the bats in the United States live in national parks. Carlsbad Caverns National Park in southeastern New Mexico, has one of the greatest populations of bats in America. This park is home to 17 different species of bats.
Not only are bats one of the most omnipresent species in the world, but they are also very beneficial to the human race and the environment.
Similar to humans, bats are mammals. They have hair, give birth to live young and nurse babies. However, bats are the only true flying mammals. Their wings are formed by a smooth, elastic membrane of skin that stretches over their arms and legs and continues to their tail.
The place where a bat lives is called its roost. Bats will change locations on a regular basis throughout the year due to their roosting needs.
“Bats live in a variety of habitats,” Dianne Odegard, outreach associate at Bat Conservation, Inc., explained. “Some bats are foliage roosters, which roost in trees. They will hang from a leaf stock and curl up like a leaf.”
|At left, habitat destruction, such as human disturbances of caves, is killing bats worldwide (Photo courtesy of the National Park Service). Next, human fear has led to the unjustified onslaught of many innocent bats (Photo courtesy of the U.S. Fish & Wildlife Service).|
“Some roost in hollow trees behind bark, some in caves and some even under bridges,” Odegard continued. “Crevice-dwelling bats easily adapt to several bridge constructions.”
“We have six major canyons with rocks and cliffs, where the bats like to live.” Briana Board, interpretive ranger at Colorado National Monument, said. “Bats can live in any cove or over-hang, whether it be a small crack or rock. They do not always need a cave.”
Habitat destruction, which in turn disturbs bats’ roosts, has been a continuous issue. Many bat species roost in buildings and bridges. Direct threats to bats occur when they are present during construction or demolition of these structures. Most of these destructions are unintentional, but negligent as people are unaware that bats reside there.
“One species, the Southern Yellow Bat, roosts in dead palm leaves,” Odegard said. “Their fur is the same color as the palm fronds. People trim these fronds unaware of the bats roosting. Suddenly, baby bats are everywhere.”
“There are a lot of bat species that live in caves and mines,” Mark Ohms, physical scientist at Wind Cave National Park, stated. “They hibernate in them, and are very susceptible to a disturbance during this hibernation.”
“If they wake up, their fat reserves are ruined,” Ohms continued. “Then, they can’t make it through the winter and will die.”
The decrease in bat population coincides with the decrease of natural habitats, such as caves, forests and ponds.
Destruction of habitat is most dangerous when it is done because of human fear. Many species of bats roost in large colonies in caves. This makes them very vulnerable because one single destructive act can kill a community of bats.
The largest bat colony in the United States, located in Eagle Creek Cave in Arizona, had 30 million to 50 million inhabitants until the 1960s. Then, human trespassers killed these bats and their habitat, reducing their population to only 30,000.
“There was a case in the South where people went into caves and clubbed bats to death,” Odegard said. “People sometimes willfully destroy habitats.”
Another reason that bats are vulnerable is that they are slow reproducers. They have the slowest reproduction rate for an animal their size. Most bats give birth once a year to only one pup.
“In the past, it’s been mostly loss of habitat and disturbance,” Ohms said. “More recently, it is the white-nose syndrome. If it continues, several bats will face extinction.”
In February 2006, about 40 miles west of Albany, N.Y., a caver saw hibernating bats that had a strange white substance on their noses, whom were surrounded by several dead bats.
By 2007, the New York Department of Environmental Conservation had identified this pandemic as white-nose syndrome, after witnessing bats with white noses, bats behaving irregularly and many dead bats in various caves.
Today, this syndrome has killed more than one million hibernating bat species in more than 15 states. It has been confirmed in at least 11 states and three units of the National Park Service system.
The National Park Service is now establishing protocols to deal with this white-nose syndrome in bat populations. The parks’ protocols range from addressing the issue on its website to informing visitors before they go on cave tours to prevent the spreading of this disease.
Research has shown that affected bats are waking up more often, every three to four days, as opposed to their normal 10 to 20 days. This causes the bats to deplete their fat reserves. About 90 percent of the affected bats die from starvation.
|At left, bats live together in places called roosts. They can roost in caves, trees, bridges, buildings and almost any crevices (Photos courtesy of the U.S. Fish & Wildlife Service). Last, white-nose syndrome, a fungus plaguing bats throughout the country, has resulted in more than one million deaths.|
“White-nose syndrome can be carried from cave to cave,” Board explained. “Some public caves have been closed to try to stop the spread of this disease, especially during winters.”
Paula Bauer, management assistant at Carlsbad Caverns National Park, works to debunk the myths about bats.
“There is a myth that bats are blind,” Bauer said. “However, many bat species have eyes and can see, in addition to their echolocation.”
Bats are certainly not blind. Their eyes are adapted for both daylight and UV vision.
However, their sight is not used for hunting insects in the dark. Instead, they have developed a highly sophisticated echolocation system that allows them to catch small insects and avoid obstacles, even in total darkness. Bats’ ability to echolocate is so acute that they can dodge obstacles that are as wide as a piece of thread.
Bats shriek and then listen to the following echoes to determine where they are in relation to their surroundings. Of course, this nighttime shrieking makes them seem even scarier.
“There’s a myth that bats like to get in people’s hair,” Bauer said. “Now, why would they even do that?”
Urban legends have led people astray. One such myth is that bats like to entangle themselves in people’s hair. In reality, bats are like most animals as they do not attack humans unless they feel threatened. Though bats may fly very close to someone, they are merely trying to eat surrounding insects.
“Another myth is that all bats carry rabies,” Bauer said. “False. Bats are not necessarily more inclined to carry rabies than any other mammal.”
“People have always associated bats with rabies,” Ohms stated. “However, people are more likely to contract rabies from cats and dogs.”
Less than half of one percent of bats have rabies. Since 1960, there have only been 40 reported cases of humans getting rabies from bats. That is only one or two cases, at most, per year.
Created by the legend of Dracula, the biggest myth surrounding bats is that they are malicious, blood-sucking creatures that prey on human beings.
Only three of the approximately 1,000 species of bats even consume blood. However, these vampire bats are by far the most famous.
The three species of vampire bats are found in Mexico, Central America and South America. There have been no species of vampire bats identified in North America.
Two of these three species only consume blood from birds. The third species drinks blood from mammals such as horses, cattle and pigs. However, it only needs to ingest two tablespoons of blood per day, which it consumes from multiple animals.
Unlike the movies that sensationalize this adaptation, bats do no actually suck blood. Instead, they make a small incision in the skin of a sleeping animal and then lap up the blood from there. Their saliva contains an anesthetic, which prevents the animal from feeling any pain.
Not only are bats less threatening than they appear, they are actually very beneficial to the environment and economy.
“One important service that bats provide to the environment and humans is consuming huge numbers of insects that attack crops,” Odegard explained. “This reduces the use of pesticides.”
“We would also miss that terribly in an economic sense,” Odegard continued. “Studies from the last couple of years have shown that bats save crop growers $3 billion to $50 billion per year.”
About 70 percent of the bat species worldwide feed solely on insects. One bat can eat up to 1,200 mosquitoes and other insects in just one hour. Bats help reduce our usage of insect-killing pesticides, which benefits nature and human health.
A few bat species in the Southwest feed on fruit, nectar and pollen. Fruit bats act as seed dispersers, while nectar-eating bats are important pollinators. Many plant species are dependent on bats for pollination.
Bats have existed in America since the era of dinosaurs. Today they rank atop the list of endangered species. The best way to help these misunderstood creatures is through educating and informing the public.
“One of the main problems facing bats are bad press, a bad reputation that is unjustified and undeserved,” Odegard stated. “People are afraid of bats because they don’t know about them and don’t see them often.”
“One of most important things someone can do for bats is talk to their friends and family about them,” Odegard continued. “Read about bats all over the world. They are very important to us.”