Published: October 23, 2008 07:02 pm            

Zoo Tales – Going batty!

N.C. Zoo is going a little batty

Bats. It’s likely that only snakes are more feared and more misunderstood than these nocturnal mammals. To help alleviate some of those fears and to help visitors better understand these unique creatures, the N.C. Zoo will hold Batology on Nov. 1 and Nov. 2.

Held at the park’s Sonora Desert exhibit in the North America region, the event will feature zoo keeper talks, demonstrations and bat feedings. (See the zoo’s Web site for feeding times.)

Bats are in the taxonomic order Chiroptera and have those same characteristics as do most other mammals. They give birth to live young (rather than laying eggs) and feed them with their milk. Bats’ most distinguishing features are their forelimbs, which have developed as wings.

This makes them the only mammal naturally capable of flight. Although some mammals, such as flying squirrels, might be erroneously thought of as flyers, they are actually gliders that can only travel limited distances through the air.

Not surprisingly, the word Chiroptera (their order) comes from the Greek words cheir (meaning “hand”) and pteron (meaning “wing”). It’s hardly a stretch, considering that the bat’s open wing is similar to an outspread human hand with a membrane between the fingers that also stretches between hand and body.

Present throughout most of the world, bats make up about 20 percent of all mammal species. The zoo’s vampire bats are one of about 1,100 species worldwide. About 70 percent of all bat diets consist chiefly of insects and other small creatures, making them insectivores. A few species are carnivores (meat eaters), but most of the rest are frugivores, feeding primarily or exclusively on fruits.

Like snakes, bats help humans in many ways. In addition to some pollinating flowers, bats eat harmful insects. By some estimates, a single bat can consume as many as 1,200 mosquitoes per hour. Bat feces, called guano, is actually a strong natural fertilizer – so strong, in fact, that people who collect it often have to wear protective masks and clothing. Almost odorless, guano is also an ingredient in gunpowder because of to its high levels of phosphorus and nitrogen.

Unfortunately, the cave mining of guano deposits can be deadly to the bat colonies themselves. In the wild, bats are highly vulnerable to disturbance to their roosts. Some species, especially those with low fat reserves, will starve to death when regularly disturbed and put into a panic state during their resting period. Many species will drop their young (called pups) when panicked, leading to further reductions in populations.

Common vampire bats (Desmodus rotundus), like those exhibited at the N.C. Zoo, are one of three species of bats that feed solely on blood, a dietary trait called hematophagy. All three species are native to North, South and Central America, ranging from the desert area of northern Mexico to Brazil, Chile and Argentina.

Compared to other bat species, vampire bats generally have a short tail membrane and small ears. Their front teeth are specialized for cutting and their back teeth are much smaller than in other bats. Their digestive system is adapted to their liquid diet, and their saliva contains a substance called draculin. This saliva, a natural anticoagulant, is now being reproduced synthetically to help heart patients and has been an inspiration to researchers for stroke treatments. Vampire bats do not suck blood but rather lap the blood at the site of the bleeding.

Bat colonies are well structured, with strong social bonds, often grooming each other and recognizing other colony bats with voice and smell. Their social structure is imperative to their survival since hungry bats that have not found food that night or are forced to stay behind are sometimes fed from others through a process of regurgitation.

They typically feed on the blood of domesticated animals such as cows, pigs and horses and require about two tablespoons of blood each day.

Although vampire bats have been depicted in folklore and films as creepy blood-suckers, they are actually beneficial to man and nature and, like so many other animals thought to be nuisances, are a vital part of our ecosystem.

Zoo visitors can daily see vampire bats in the park’s Sonora Desert exhibit.



Tom Gillespie lives in Trinity and is a journalist and public affairs specialist at the North Carolina Zoo. For more information on the zoo’s plant and animal collections, special events and education programs, go to their Web site at www.nczoo.org

        

• Click to discuss this story with other readers on our forums.