*Bats are extraordinary pollinators and insect-eating creatures. These admirable masterpieces are the unsung heroes of the night sky. The last week of October is known as Bat Week. It’s a time to celebrate these beauties and to recognize their plight.
Bats have inhabited the planet for 50 million years. There are approximately 1,300 bat species worldwide, including 47 in the U.S. and 18 kinds in Canada.
Bats are the only mammals capable of flying. Their wings consist of a double membrane adjoining a bony structure resembling a human hand. The extra long fingers and membrane run downward to include a tail. Only the thumbs are free, and the thumb claws are used for climbing and turning around during roosting, or, perching. For bats, that means hanging upside down.
When most animals hang upside down, blood rushes to the head, but not in bats. They have unique valves in their veins to keep the blood moving through their bodies when inverted. Specialized tendons in their feet allow them to relax and conserve energy. This position also allows for easy takeoff.
How much energy do bats use to fly? Lots. Some bats flap their wings between 10 and 20 beats every second, reaching speeds of between four and 22 miles per hour (mph). In order to achieve these speeds, their heart must pump at about 1,000 beats per minute.
Bats have adapted to high-energy needs by lowering their body temperature. When the surrounding temperature drops, an internal adjustable thermostat enables an inactive body temperature to fall from 113 to 41 degrees Fahrenheit. Another energy saving mechanism is to drop the heart rate from 200 to 100 beats per minute while resting, moving to only five beats per minute during hibernation.
To hibernate, bats must have a 40 percent fat reserve. It’s a good thing that they are excellent hunters. One bat can consume more than 600 mosquitoes in an hour. They also feast upon moths.
A little brown bat can devour up to 1,200 insects, including mosquitoes, within one hour.”
To catch insects most bats use echolocation, or, sonar, to locate their prey. In addition, bat sonar enables navigation with ease in total darkness. High frequencies are usually emitted from the voice box and when the waves hit an object the bat’s sensitive ears hear echoes and differentiate between trees, rocks or prey.
All Nature’s creatures have marvelous adaptations and moths, too, are no exception. They have evolved fine hairs, which detect bat sonar. When a bat hunts for a moth it is analogous to high-tech warfare between modern fighter planes. Moths are able to zig-zag and free fall like sky-divers. When moths free fall, bats somehow calculate the angle of incidence and make a pouch using their tails to form an inverted scoop, often catching their prey. And once caught, they rapidly chew the moth up to seven times per second.
According to a group of researchers lead by Boston University, bats as insectivores save American farmers an estimated $22.9 billion annually.”
Since 2006, the white-nosed syndrome, named for the white fungus that infects the skin of the muzzle, ears and wings of these hibernating mammals, has felled millions of bats in 32 states and seven Canadian provinces. A recent discovery that ultraviolet radiation kills the fungus is an important first step in finding an antidote to save the bats.
Windmills have also annihilated hundreds of thousands of bats each year. In 2015, the American Wind Energy Association, or, 90 percent of the turbines, agreed to idle its blades during spring and fall bat migration peaks. This measure is helping to annually reduce bat fatalities by about one third.
In addition to the deadly fungus and turbines, neonicotinoid insecticides poison the bat’s autoimmune systems. And a poisoned bat is more susceptible to contracting the white-nosed syndrome. It’s yet another reason why the U.S. lawmakers need to follow the European Union’s (EU) lead, and ban all bee and soil killing neonicotinoids.
Like all creatures in today’s hot human-dominated world, bats are suffering from habitat destruction. No habitat. No bats. Fewer insectivores. Fewer pollinators. Accelerating the Sixth Mass Extinction.
It’s up to each of us to lend a helping hand and turn this around by working with Nature, not against our life support systems. Refuse to purchase man-made insecticides, herbicides, fungicides and miticides.
Consider building a small bat house. It can hold up to 100 of these masterpieces, while protecting your food-bearing trees and raised beds from unwanted plant-eating insects. It can also protect your family and pets from disease-carrying mosquitoes!
Dr Reese Halter is an award-winning broadcaster, distinguished conservation biologist and author.