Bats Are Important
Bat Conservation International
The Earth without bats would be a very different and much poorer place. More than 1,300 species of bats around the world are playing ecological roles that are vital to the health of natural ecosystems and human economies.
Many of the more than 1,300 bat species consume vast amounts of insects, including some of the most damaging agricultural pests. Others pollinate many valuable plants, ensuring the production of fruits that support local economies, as well as diverse animal populations. Fruit-eating bats in the tropics disperse seeds that are critical to restoring cleared or damaged rainforests. Even bat droppings (called guano) are valuable as a rich natural fertilizer. Guano is a major natural resource worldwide and, when mined responsibly with bats in mind, it can provide significant economic benefits for landowners and local communities.
Bats are often considered “keystone species” that are essential to some tropical and desert ecosystems. Without bats’ pollination and seed-dispersing services, local ecosystems could gradually collapse as plants fail to provide food and cover for wildlife species near the base of the food chain.
Pest control
Insectivorous bats are primary predators of night-flying insects, and many very damaging pests are on their menu. Pregnant or nursing mothers of some bat species will consume up to their body weight in insects each night.
The millions of Mexican free-tailed bats at Bracken Cave in Central Texas eat tons of insects each summer night. And a favorite target in the U.S. and Mexico is an especially damaging pest called the corn earworm moth (aka cotton bollworm, tomato fruitworm, etc.) that attacks a host of commercial plants from artichokes to watermelons. Worldwide crop damage from this moth is estimated at more than $1 billion a year, and research in 2006 concluded that freetails save cotton farmers in south-central Texas more than $740,000 annually. Throughout the United States, scientists estimate, bats are worth more than $3.7 billion a year in reduced crop damage and pesticide use. And that, of course, means fewer pesticides enter the ecosystem.
Pollinators
From deserts to rainforests, nectar-feeding bats are critical pollinators for a wide variety of plants of great economic and ecological value. In North American deserts, giant cacti and agave depend on bats for pollination, while tropical bats pollinate incredible numbers of plants.
Most flowering plants cannot produce seeds and fruit without pollination. This process also improves the genetic diversity of cross-pollinated plants. A few of the commercial products that depend on bat pollinators for wild or cultivated varieties include: bananas, peaches, durian, cloves, carob, balsa wood, and agave.
Seed dispersers
Vast expanses of the world’s rainforest are cleared every year for logging, agriculture, ranching and other uses. And fruit-eating bats are key players in restoring those vital forests. Bats are so effective at dispersing seeds into ravaged forestlands that they’ve been called the “farmers of the tropics.”
Regenerating clear-cut forests is a complex natural process, one that requires seed-scattering by birds, primates and other animals as well as bats. But birds are wary of crossing large, open spaces where flying predators can attack, so they typically drop seeds directly beneath their perches. Night-foraging fruit bats, on the other hand, often cover large distances each night and they are quite willing to cross clearings and typically defecate in flight, scattering far more seeds than birds across cleared areas.
And many of the bat-dispersed seeds are from hardy pioneer plants, the first to grow in the hot, dry conditions of clearings. As these plants grow, they provide the shelter that lets other, more delicate plants take root. Seeds dropped by bats can account for up to 95 percent of the first new growth. The pioneer plants also offer cover and perches for birds and primates, so they can add still more, different seeds to the mix that can lead eventually to a renewed forest.
Threatened
The world is a dangerous place for bats. Although they provide vital environmental and economic services, bat populations are declining around the globe, largely as a result of human activity.
One such example is the plight of fruit bats, which have a brutally hard life in Sulawesi, an orchid-shaped island in the heart of Indonesia. A remarkable 22 species of fruit bats live on the island and some of them are found nowhere else. But their numbers are being decimated by overhunting for the commercial “bushmeat” trade, and their treatment on the way to market can only be described as torture.
The International Union for the Conservation of Nature (IUCN) lists 26 bat species as Critically Endangered, meaning they face an imminent risk of extinction. Fifty-one others are Endangered, and 954 bat species are considered Vulnerable. Bats also are among the most under-studied of mammals. The IUCN lists 203 bat species as “Data Deficient” — there is simply too little information available to determine their conservation status, and over 150 newly described species have yet to be added to the IUCN Red List and have yet to be formally assessed.
Because bats reproduce slowly, with females of most species giving birth to only one pup per year, recovery from serious losses is painfully slow and tenuous, at best. It is often difficult to spot significant declines in such species until their situation is dire.
Loss of habitat remains the most widespread peril worldwide. The forests that many bats use for roosting and/or foraging for food are disappearing at a frightful rate — shrunken by timber harvests or cleared to make room for farm crops, mining operations, cattle pastures or cities. This is especially critical in the tropical rainforests, with both a rich diversity of bats species and a precipitous loss of woodlands.
Countless bats are being driven out of roosts in caves and abandoned mines because of inappropriate guano mining or thoughtless tourism. During the winter months, large numbers of bats hibernate in caves and mines. If roused from hibernation, bats can burn through the stores of fat they need to survive the winter.
In much of the world, bats are still casually killed because of harmful myths and misplaced fears. In Latin America, whole colonies of beneficial bats are routinely destroyed in the mistaken belief that all bats are vampires. (In reality, only three of the more than 1,300 bat species feed on blood and all are in Latin America.)
In regions such as Southeast Asia and the Pacific islands bats are hunted, both as bush meat for local consumption and commercially for markets and restaurants. Large, fruit-eating bats are the primary targets. Bats are also used in some folk medicines.
In North America, meanwhile, over 5.7 million of bats have been killed by White-nose Syndrome (WNS), a wildlife disease that continues its spread across the continent. Caused by a cold-loving fungus, WNS attacks hibernating bats, causing mortality rates that approach 100 percent at some sites. The disease was first spotted in a cave in Upstate New York in February 2006 and has since expanded across the eastern half of the U.S. and Canada. [Earlier this year, Texas Parks and Wildlife confirmed the presence of the fungus in 6 North Texas counties.]
Despite tireless scientific efforts to find a solution, the disease is killing huge numbers of bats. Until the arrival of WNS, two Endangered U.S. species, the Indiana myotis and gray myotis, were showing promising signs of recovery. That now seems doubtful. And scientists predict that the once common little brown bat, will be reduced to just 1% of its pre-WNS population numbers by 2030.
The dramatic growth of wind energy throughout much of the world is also taking a huge toll on bats. Scientists estimate that hundreds of thousands of bats are killed each year in the U.S. by collisions with the spinning blades of wind turbines or rapid pressure change at turbines that can rupture blood vessels.
Misunderstood
Bats are wonderfully beneficial creatures that provide invaluable services to both natural ecosystems and human economies around the world. Yet they are also among the most misunderstood of animals — routinely feared and loathed as sinister denizens of the night.
Common myths and the truth
- Blind as a bat. Bats see quite well and most use a unique biological sonar system called echolocation, which lets them navigate and hunt fast-flying insects in total darkness. Using sound alone, bats can see everything but color and detect obstacles as fine as a human hair.
- Bats are flying mice. Bats are mammals but they are not rodents. In fact, they are more closely related to humans than to rats and mice.
- Bats get tangled in your hair. Bats are much too smart and agile for that.
- Bats are blood suckers. There are three vampire bat species that feed on blood; only one targets mammals. All vampire bats are limited to Latin America. A powerful anticoagulant found in vampire saliva, which the bats use to keep blood from clotting, has been developed into a medication that helps prevent strokes in humans.
- All bats are rabid. Bats, like other mammals, can be infected with the rabies virus and some of them are. But the vast majority of bats are not infected. However, a bat that can be easily approached by humans is likely to be sick and may bite if handled. Do not touch or handle a bat or any other wild animal and there is little chance of being bitten. Teach children to never handle any wild animal.
Everywhere
Bat conservation is particularly compelling because it impacts us all. If you think that you don’t live near bats or that your life isn’t impacted by bats, think again! Bats are literally everywhere — except for the regions surrounding the North and South poles, and remote islands. Unlike the picture painted by myths and superstitions, bats do not live their lives isolated in dark caves; rather, they interact on a daily basis with the same fields, forests, and waterways that we do. Likewise, their services to the environment, to agriculture, and to human health and welfare are available all around us, sustaining our ways of life. There is a close connection between bats and people around the globe, so bat conservation is in our common interest.
Global bat species richness
Bats are uniquely adapted to live in virtually all environments. With more than 1,300 species of bats in the world, spread across six continents, and ranging in size from smaller than your thumb to as heavy as 2.5 lbs. (1.2 kg), it makes sense that different types of bats have evolved to live in different environments — from arid deserts to tropical rainforests, and everything in between. In fact, depending on the species and location, bats are known to spend time living in all of these types of roosts: caves, mines, rock and cliff crevices, tree hollows, plant foliage, tree bark, roofs of homes, attics, football stadiums, bridges, artificial bat houses, etc.
Bats are cool!
Yes, bats are definitely cool. They display an amazing diversity as species evolved over at least 60 million years to survive in wildly varied habitats and food chains.
Here’s a few other things you might not know about bats of the world:
- The forelimbs of bats form webbed wings, making them the only mammals naturally capable of true and sustained flight.
- Bats are exceptionally vulnerable to extinction, in part because they are among the slowest reproducing mammals on Earth for their size. Most bats moms give birth to a single pup at a time, for good reason. Baby bats can weigh up to one-third of their mother’s body weight. To put that into perspective, just imagine birthing a 40-pound human infant!
- The largest bat colony in the world roosts in Bracken Cave, Texas, where over 15 million Mexican free-tailed bats emerge from the cave in large columns to feed on surrounding farmland. This cave is a maternity colony, where females of this species migrate from Mexico every year to give birth.
- The Brandt’s myotis of Eurasia is the world’s longest-lived mammal for its size, with a lifespan that sometimes exceeds 38 years.
- Bats range in size from the tiny Kitti’s hog-nosed bat, better known as the bumblebee bat, that weighs less than a penny, to the golden-crowned flying fox, which weighs 2.6 lbs. and has a wingspan of up to 5’6”.
- You’ve probably heard of bats being nocturnal, but what about diurnal? The Samoan flying fox is the only bat species known that forages almost exclusively during the day!
- The range of habitats and diets of bats is highly varied. Bats are known to eat insects, fruit, nectar, fish, amphibians, reptiles, birds, small mammals and even other bats.
- Frog-eating bats identify edible from poisonous frogs by listening to the mating calls of the males. Frogs counter by hiding and using short, difficult-to-locate calls.
- The pallid bat of western North America is immune to the stings of the scorpions and centipedes on which it feeds.
- Fishing bats have echolocation so sophisticated that they can detect a minnow’s fin, as fine as a human hair, protruding only two millimeters above a pond’s surface. And African heart-nosed bats can hear the footsteps of a beetle walking on sand from more than six feet away.
- The tube-lipped nectar bat of Ecuador has what is believed to be the longest tongue relative to body length of any mammal — up to 1 1/2 times as long as its body.
- The Honduran white bat, with its yellow nose and ears, roosts in ‘tents’ it builds by nibbling on large leaves until they fold over.
- Since at least 1974, biologists have known that some male bats sing very much as songbirds do, and they warble for the same reasons: to defend territories and to attract mates. Researchers have discovered that the tunes of some bats are even more complex and similar to bird song than first suspected. These bats’ melodies are structured, have multiple syllables, phrases, repeated patterns, and, of course, rhythm. Their songs also have syntax, meaning rules for how the phrases can be combined. But the rules are flexible, and a bat can improvise, singing a song his way. So far, scientists have identified 20 species of bat troubadours around the world.
- Bats are one of the most diverse groups of animals on earth. Their faces alone vary from the puppy-dog look of fruit bats and flying foxes, to the compact faces of insect eaters and the long snouts of pollinators that reach deep into flowers for nectar.
“Bats are Important” is excerpted from the October 2017 issue of The Cattleman magazine.