Joel Tigner

JOEL TIGNER is a stocky man, his black beard shot with silver.Like the creatures he loves, he ventures out at night to work long, solitary hours while most people are tucked in bed.He sets up strange-looking devices called mist nets and harp traps in marshlands, secluded streams and the mouths of caves.He crawls into the bowels of the earth and wades through waist deep murky water in abandoned mines.He has encountered rattlesnakes and even a mountain lion that came to drink in a forest pond where his nets were set.

Tigner is worried about Townsend's bats.People have locked them out of their winter homes.For eons bats slept long winters in Black Hills caves, and since the 1800s, in mines.They have been excluded from tourist caves, and many abandoned mines are collapsing or have been sealed to avoid liability.

"On the other hand," says Tigner, eye to eye with a big-eared, hairy creature in his gloved hand, "there is the big brown bat –– the sparrow of the bat world.They are immensely opportunistic in finding habitat, and they're quite hearty.Their numbers are probably not declining significantly."He weighs the brown and measures its wing, then stands full height and releases it with the gentle admonition: "Let's try to be a little more careful in the future."

Most people wouldn't know the difference between a Townsend's and a brown; many wouldn't care.A fair number wish all bats would migrate south for winter and never return.With the possible exceptions of prairie rattlers and skunks, few creatures are as reviled.Some believe bats are infected with rabies.Others see them as flying mice.Still others find them too scary-looking to behold, vampirish and evil.
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Not Joel Tigner.

He has been fascinated by bats since elementary school.Though he studied psychology rather than biology as a student in North Carolina, he explored abandoned mines in his spare time, looking for bats.Later he got a graduate degree in public health, but he couldn't shake his fascination with chiropterans, nocturnal mammals with forelimbs modified to form gossamer wings.

Today the Batman of Rapid City studies bats and their shrinking world.He works with government biologists to preserve and restore bat habitat.He presents bat slideshows at the Cleghorn Fish Hatchery in Rapid City, Badlands National Park, and the Booth Fish Hatchery in Spearfish.Sometimes he puts a favorite bat in his pocket and goes to schools to educate youngsters about the importance of bats in the natural order.His goal is to save bats from defamation and decimation.

His first call is to dispel the myths that bats attack people and other animals, and that they often carry the rabies virus, the most frequently-cited reason for their wholesale extermination.Both beliefs, Tigner says, are false.

From 1993 to 1999, 18 rabid bats were identified in South Dakota, Tigner said.That compares with the 752 other rabid animals found in the state in those six years –– 543 rabid skunks, 85 cows, 44 dogs, 37 cats, 26 horses, and 17 other animals including sheep, foxes, badgers, bison, pigs and raccoons.Tigner said bats are not a significant link in the spread of rabies.

Neither are bats aggressive, Tigner insists.They are a threat only to people who handle them."Even the rare rabid bat is not very dangerous," he said."They're at the bottom of the pecking order; they're not designed for aggressive behavior.If you leave them alone they're more than happy to return the favor."

Tigner has rehabilitated injured bats for years, having as many as 28 in his care at one time; he even finds them attractive, not to mention personable and intelligent."They quickly pick up on when it's time to eat," he said."They have personalities.One brown long-eared bat I had was a very acrobatic flyer.Instead of eating from my hand, he insisted on power diving from an upper shelf to snatch food from my hand in flight."

Tigner said bats even play tricks on one another, and at least in captivity they may segregate by species and take food from their cousins.Some bats like to be held, while others never grow accustomed to people.One bat he took to school presentations would hang inside his pocket and peak out when Tigner scratched on his shirt.

Is that the whole story about bats?They're either a loathsome creature to be despised and killed on sight, or a helpless endangered animal to be protected from harm?Tigner says they also contribute mightily to our comfort, and even our economic well-being.

Bats are very diverse worldwide.Tigner said about 1,000 of the Earth's 4,000 mammal species are bats.In the Americas they are the main predator of night-time insects, perhaps the greatest contributors to healthy ecosystems.

It is estimated that the hoard of bats living in Bracken Cave in Texas eat the equivalent weight of 32 African elephants in a single night.How much money this saves ranchers and farmers who buy less insecticide and have more crops to harvest is impossible to know, but it must be substantial.

The economic impact in South Dakota might be less, because we have fewer bats.
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But a single bat can down a lot of mosquitoes, Tigner said.He netted a Townsend's bat near Sturgis one evening just after dusk.He weighed it, banded it and recorded the data."Less than two hours later, I netted the same bat coming back to the cave," he said."It had gained 40% of its body weight in less than two hours by gorging on mosquitoes and other night-flying insects."A Townsend's bat may feed two or three times a night, consuming the equivalent of its total weight by morning.A big brown bat can eat up to 500 mosquitoes per hour.

Tigner's professional work with bats began in England in 1988, when his wife was stationed there with the U.S. Air Force.The Tigners arrived in Rapid City in 1991, and today Joel is among South Dakota's leading authorities on bats.He runs a bat consulting business, Batworks, from his home.His wife, also a bat enthusiast, is a nurse at Rapid City Regional Hospital.Their 19-year-old daughter has lost much of her interest in chiropterans, but their nine-year old son often goes batting with Joel.

His first autumn in the Black Hills, Tigner read existing biological research on South Dakota bats.He found the studies spotty and incomplete.Some had literally been shotgun surveys; people had shot foraging bats to determine species.There was little data on population or distribution, and no information on how weather influences annual populations.He would have to establish baseline statistics himself.

Armed with the scant data available, Tigner began a winter survey of hibernating bats, meticulously recording data.He located a number of sites that he would revisit in subsequent years to compare populations.

When summer came, Tigner worked with biologists Bill Aney and Brad Phillips on a National Forest Service-funded summer population survey.
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Working alone much of the time, but with interested parties and collaborators when possible, Tigner visited dozens of sites a month, capturing bats as they left caves and mines or as they flew low over bodies of water, feeding on night-flying insects.He recorded information on every bat captured –– species, weight, length of forearm to help distinguish between similar species with overlapping ranges, sex, and for females, reproductive condition, whether lactating, non-lactating or pregnant.

The first two years Tigner banded bats so he could discover migration patterns when he recaptured the same individuals.One silver-haired bat he banded at a pond near Whitewood was later recaptured near Denver.

A pervasive source of friction between bats and people is that contact commonly occurs in human homes.In four of five homes they inhabit, bats go undetected, Tigner said.But like juveniles of all species, bat pups are inclined to get into trouble, especially in early summer when the pups are learning to fly.Unlike juveniles of other species, encounters with humans often end disastrously for young bats.After all, these are not cute little Bambis or cuddly bunnies –– for many people, they are among the homeliest and scariest creatures they have encountered.

One might wonder why a bat would choose to roost in a house at all.First, many attics are a fine substitute cave, Tigner says, providing darkness, a bat-pleasing temperature and a sheltered space where pups can learn to fly.Also, bats have lost much of their natural habitat.He said 10 of the 11 species found in the Black Hills commonly use trees for day roosts, maternity roosts and nursery roosts, taking shelter beneath loosened bark on snags in larger trees.One species, the silver-haired bat, uses tree cavities for maternity roosts.But there aren't many big, old trees left in the Hills, and there is stiff competition for cavities.Cavity nesting birds, squirrels and other forest dwellers can readily evict a bat.Birds, snakes, raccoons and many other creatures also harass, kill and eat bats.The latest Black Hills National Forest Land and Resource Management