Dark, swooping, mammals that fly, mouths open, teeth bared, through evening skies, after hanging upside down by the thousands in caves all day, capture the imagination. Dracula, Batman, Silverwing. Bright, stinging eyes and menacing, fangy grins, oversized ears with thin veins pulsing, hearing every sound, tracking every movement, waiting for the right moment to swoop down and bite. Vampires shape-shifted into flying mammals, symbols of ghosts, death, disease ... the heavily mythologized bats are the real deal.
And these strange little creatures populate our nights. They invade our homes, sometimes without us knowing. They get called out in newspapers for rabies, for sheer fright factors. As much as we learn about bats, there's much more that we don't, and can't, know.
Brian Schaetz aims a yellow slingshot at the trees above the River Raisin in Lenawee County. He attaches a fishing line and shoots the line over the tree, then lowers it to Olivia Munzer standing in the river below. Munzer ties a line of thin black rope to the fishing lure, and Schaetz reels the rope back through the trees, looping it over a branch. Rope in hand, he jumps down the bank, ties the two ends together, and threads a 30-foot net onto both ropes. Then, with Sarah Friedl holding a second rope on the other side of the river, they hoist the thin, fishnet-stocking net into the air.
Extended above the river, the net is invisible to the naked eye and, hopefully, says Munzer, "the bats won't detect it with their echolocation." Schaetz, 32, Munzer, 30, and Friedl, 26, are biology students at Eastern Michigan University and out tonight to study the evening bats in Lenawee County. The bats use the River Raisin, without trees to fly through and ample mosquitoes hovering above it, as a highway through southern Michigan and, eventually, the Great Lakes.
Munzer, the leader of the project, wants to know evening bats' travel plans. Many Michigan bats fly south to caves in Kentucky and Tennessee to hibernate; others fly to abandoned mines up north, and some end up in homes or barns. "We don't know where the evening bats go yet," she says. Lenawee County "is the only place where we've actually found the evening bats in Michigan. We don't know how long they've been here or if they're expanding their range." On this, the last weekend in September, Munzer is hoping to catch one last bat before they go into hibernation.
In 2006, Schaetz and Munzer spent the summer netting and tracking bats around the River Raisin. During the day, they tracked bats to the trees where they roosted and recorded where they lived. At night, they caught bats to see which were flying and when. In two years, they caught 75 evening bats and confirmed 29 roost trees. Now, Munzer heads up the project and Schaetz helps. This evening, Friedl, who's currently studying whitefish spawning in the Detroit River, came along as an extra hand — familiar with bat research and the project, she's also inoculated against rabies.
As they wait, Munzer sets up the bat processing materials on the white lid of a large Tupperware bin, mosquitoes buzzing around her head. The sun sets early, and they use their headlamps as little as possible to keep the bats from flying away. Bats can see and hear, Munzer warns, they know we're here. In the background, crickets chirp, frogs gulp, and the anabat, an electronic device that picks up the bats' echolocation, emits a scratchy pulse whenever a bat flies by.
As the sun drops, so does the temperature. Though bats usually won't fly when the temperature dips into the 50s, some are flying tonight. They soar above the net and scoot under it. On a busy night, they've caught 32 bats here, on a slow night, they won't catch any. Schaetz watches a bat scoot under the net, skimming the river. Hopefully, some bats will be off their game — the bats that aren't paying attention are the ones that get caught.
A YEAR FOR BATS
This year, bats and rabies were all over the media. August 25: Grand Rapids Press, "Bats Carrying Rabies on Rise." September 8: CDC hosts the first annual World Rabies Day. September 9: The Associated Press and The Detroit News say, "Reports of Rabies Rise in Michigan." September 27: The Office's Michael Scott organizes Fun Run for Rabies. October 17: The Detroit Free Press, "Michigan Cases of Rabies Surge, Prevention Urged." By the end of October, 202 cases of rabies were reported, and 95.5 percent, 195, were in bats.
"This summer was unusual," says Dr. Kimberly Signs, zoonotic disease epidemiologist with the Michigan Department of Community Health, "very unusual." It started with more people calling about bats in their homes in July and August. Then, more and more bats were caught in homes and sent to the Department of Community Health for testing. Signs isn't sure what caused the increase, but this year has proved dramatic compared to the average year when only 40 bats tested positive for rabies, and even the previous peak year of 2000 when 61 did. And, the percentage of bats testing positive is higher — in 2006, 79 percent of the animals that tested positive for rabies were bats; in the peak year of 2000 some 91 percent were.
More bats in Michigan houses, bats falling over themselves and foaming at the mouth with rabies. There's manpower invested in preserving and understanding these animals, and keeping them out of homes — so what's going on here?
MICHIGAN BATS: A PRIMER
Michigan has nine bat species: big brown, little brown, hoary, red, eastern pipistrelle, evening, Indiana, northern, silver-haired. The big brown bat is Michigan's most common; wings outstretched, it's a foot long, on average. "They're not a monster bat," says Chris Percha, "the bat guy" and owner of Michigan Wildlife Management. Little brown bats are the second most common, half the size of the big brown. What they lack in size, they make it up in cuteness. "Big browns are ugly, facially," says Percha, "and the little browns have a teddy bear looking face."
The red bat, with a pouf of red fur, small eyes and pert nose, is, according to Allen Kurta, bat researcher and professor at Eastern Michigan University, "the most handsome of all the animals in the Great Lakes. But, it has a nasty disposition." One hundred years ago, red bats flew during the day, but that's long gone. Today, they look like pine cones or leaves hanging upside down in trees. The silver-haired bat, with upturned, snooty nose, and a grin that extends to its huge curved ears, also sleeps in crevices in old trees. Hoary bats have a small face and dog-like nose poking out of a thick, dense mane of black hair frosted white at the tips. After spending the summer in forests, they migrate, sometimes with groups of birds, to coastal regions for the winter.
Michigan's bats, Kurta admits, aren't the world's most interesting. They are, however, helpful. Michigan bats fly, mouths open, echolocating, and use their wings to scoop prey into their mouths. Each night, there are hundreds of thousands of bugs and tens of thousands of bats. "If something ever happened to the bat population," says Schaetz, "the insects would go out of control."
Friedl pulls a large bottle of Mountain Dew out of the Tupperware bin and takes a sip. Schaetz passes around a bag of chili lime peanuts. Friedl and Munzer pull the hoods of their sweatshirts tight over their faces to keep warm and protect their heads from mosquitoes. In the background, the anabat screeches and whines. "The anabat is a tease," says Schaetz. Sometimes, the bats corral insects against the net and eat them, making it sound like they're caught and giving the researchers away when they hurry over with their flashlights.
At 9:06 p.m. the anabat explodes with agitated squeaks and scratchy thumps. Friedl and Schaetz hurry to the river. Curled up in the net, the bat looks around, surprised, sending out annoyed shrieks, like a child caught playing where it's not supposed to. Friedl and Schaetz wade into the river and pull the net down. "What is it?" Friedl asks Schaetz who is prying the squealing bat from the net.
"A big brown," Schaetz replies.
Friedl giggles. "I forgot how much noise they make," she says.
Schaetz pulls the bat off the net and tucks it into a small mesh bag. They raise the net and walk ashore. In the bag, the bat squirms and flails; a high-pitched squeal emanates from Schaetz's front pocket. At the Tupperware processing station, Munzer looks it over, dog-like face poking out of a mass of brown fur, tiny, black, beady eyes watching us. It's an adult female brown bat, and its forearm measures 44 millimeters. It's definitely a big brown. They examine the wing membrane that, when stretched, resembles thin leather; a spider web of veins shows through the translucent dark brown skin. Using a tiny metal hole punch, Friedl punches the number 223 in the bat's wing, to mark the bat in case they catch it again.
The bat opens and closes its mouth, tiny pin-point rows of teeth flash as it echolocates and squeals. Munzer turns it over and strokes its back, a bony mass of soft, silky fur. The bat quiets for a moment, but picks its shrieking up again as soon as the massage ends. Schaetz pushes the bat into an orange plastic canister, like a large pill bottle, to weigh it — 20 grams. The bat, says Munzer, looks healthy; still they'll take it back to their field house to check it for parasites later that night.
Examination over, Schaetz puts the bat in the mesh bag, ties it shut, and hangs it on a small tree branch. The bat curls upside down, finally quiet. The moon, heavy and low, reflects bright white in the river. If the moon is too full, says Schaetz, the bats don't fly because the owls can see and catch them. Munzer shivers, the temperature has dropped to 57 degrees Fahrenheit. The anabat is silent.
At 10:40, the full moon's reflection lighting up the river, the three researchers pull the nets off the ropes and pack them away in plastic bags. They lug their supplies, and the mesh bag holding the last bat of the season, back to the field house where they shower and open a beer.
A BAT'S YEAR
Bats spend up to nine months of their year, from fall through spring, hibernating, curled upside down, wings wrapped around them like a blanket to keep warm. In spring, they wake up and fly to southeast Michigan, have their babies, usually one or two per mating pair, raise their young, and start storing up fat for next winter. In midsummer, young bats are learning how to fly and they end up in living rooms or attics. "Bats who get in are disoriented and juvenile," Munzer says. "They don't know what they're doing." Other bats crawl into houses and take up roost in attics, hiding in crevices and under the warm, inviting wall insulation. That's where Michigan's bat men come in.
MAN VS. ROOF
Joe Willis, 25, animal control technician with Bat Specialists of Michigan, stands in front of the large, brown siding and stone house in Brighton. A black and white-going-grey baseball cap with a Detroit Tigers D on the front shades Willis's face from the sun. Around his waist, the tools of his trade, large scissors, a tape measure, and tubes of caulk hang in a tool belt. Bats, he says, judging by the guano left on the house's roof and the oily slick left by their fur, have been getting into the second floor through two construction gaps in the front of the house, spaces that builders left open to put shingles on the roof, but never filled in. Now, Willis is here to exclude the bats, he's caulked over the two spaces, and left small white PVC pipe one-way doors poking out of the house like awkward spouts.
When the bats fly out, Willis explains, they won't be able to get back in. Bats, with wingspans over a foot, can't just fly into a house; they have to land first and pull themselves together. The PVC pipes, one-way doors, protrude from the house just far enough to take away the bat's landing strip. After 30 days, he'll return to take out the one-way doors and seal the house for good. Still, bats are territorial, and will try to get back into their roosts regardless of PVC pipes, so Willis heads around back to patch up the remaining gaps.
Willis fell into bat exclusion and animal management, the family business, through his uncle, John Sullivan. Willis has worked with Sullivan for eight years, through his time studying communications and computer science at University of Michigan-Flint, and now full time. Bats make up most of his business; Bat Specialists did 317 exclusions this year. "Most houses have bats," he says, "and they don't want to admit it."
Willis props a ladder on the edge of the garage roof and climbs, mountain-goat-style, to the peak of the roof, one white Zoon earphone dangles from around his neck like a charm, the other is in his ear, playing sports talk radio. He walks along the top of the roof and then scoots down, caulk gun in hand, to the gap, where the second floor dormer meets the roof. Hanging onto the roof with one hand, he squirts white caulk into the gap (it'll dry clear) then smoothes it. Satisfied, he climbs back up to the peak, walks back to the edge, and climbs down.
One gap left, Willis moves the ladder to another spot, this time behind the house, and climbs up again. As he climbs, he kicks pine needles off the roof, sending them flying, and scenting the air with drying pine. "The gap is so big that it needs screen behind it," he says, "or the caulk will run out." With two screens cut to size, Willis pushes an earphone into his ear, hurries up the ladder, scrambles onto the roof and back to the gap. He wedges the small rectangular wire screens in the gap, then pushes them to fit. Above him, the late October breeze dislodges leaves that float down, littering the ground with drying yellow and red leaves. Willis snaps the screens in place and seals them with caulk, spreading it smooth with a plastic spatula. Then, caulk gun in hand, he climbs down.
MICHIGAN'S BAT MEN
Bats don't always roost in the attic, says Frank Frick, owner of Bat Masters, "a bat removal and exclusion specialist" that works throughout southeast Michigan. Usually they stay under the insulation and in any space in the ceilings, floors or walls. A full-grown bat doesn't need much room to get inside, just a quarter-inch opening. "Take a standard No. 2 pencil," Frick explains, "cut an inch-and-a-half off, and that's the size slit a bat needs to get in." If they can get their nose into a crack, they can flatten their bodies and squeeze through.
A typical Michigan house, says Robert Boyd, franchise owner of Critter Control in southwest Oakland County, has between five and 17 construction gaps that bats can squeeze through. Construction techniques have affected how bats roost. The big trees that bats used to roost in have been chopped down and, over time, bats have moved into homes instead.
Of course, bats also get in through the front door. In the evening, when the doors are left open, bats swoop in, settle down in curtains or under a chair, and wake up later that night, trapped. At that point, "tennis rackets are common," Boyd says, chuckling, but "the best way to do it is to remain calm, watch where the bat lands, let it rest for a while, then slowly approach it. Put on heavy gloves, then take a box or coffee can and place it over the bat. Slide the lid under it and take it outside and let it go." Or open the windows, turn the ceiling fan off, and let the bat find its way out using the air currents.
Boyd says bats are common in houses. As many as 15 to 20 houses in his area, west of Woodward to Wixom, see bats each night. This is "prime bat area" because there are homes with lots of gaps next to swamps, ponds and forests. Frick says he usually finds pockets of bats in newer structures, those built within the last 10 or 15 years.
One bat isn't a big deal. When you see more than one, the bats are living inside your walls. You'll hear a "noise like pitter patter, like raindrops at nighttime," Boyd says. Or, look for the bat droppings, or guano. "They look like a burnt Rice Krispy," he says. "They crumble into fine particles when they're touched," and they're pungent, with a hard-to-describe odor, "like a cross between coffee and chocolate."
Rabies only claims one or two American lives each year. The last case of rabies in humans in Michigan occurred in Hillsdale County in 1983 from a rabid bat bite. Bats are always the species with the most positive tests for rabies, says Signs. "We don't understand as much about rabies in bats as we do in other species. It hasn't been as well studied." Rabies travels along nerves, through the brain stem and into the brain. Animals with rabies, Signs says, have abnormal behavior. They'll find you during the day, instead of at night, and they're not afraid of you. They'll stumble toward you, slow and lethargic, or foaming-at-the-mouth aggressive.
When the Department of Community Health gets animals for testing, it needs the brain intact (don't smash the bat in your house over the head). Researchers open the bat's skull and collect the brain tissue. Then they use a direct fluorescent antibody test. The brain will glow neon if the animal has rabies.
It is treatable, if you get a shot of rabies immune globulin and five follow-up vaccines before the symptoms — headache, fever, irritability — set in. If you don't, the symptoms escalate into delirium, paralysis, and all but inevitable death.
BAT MASTERS AT WORK
Greg Frick, 29, and Chuck Wagenbach, 37, bat exclusion specialists with Bat Masters' "friendly" bat outline drawn on their bright orange-yellow T-shirts, set up ladders and arrange their equipment outside a Sterling Heights house. Their boss, Frank Frick, 54, oversees the job, watching them through sunglasses that block out the late October sunlight.
In mid-September, Frick and his crew installed 11 check valves, small rectangular boxes with wire flaps that let bats out, but not in, over gaps in the house's roof. Now, a month later, certain that the bats have all left, they're back to take out the check valves and seal up the house.
Greg climbs up the ladder, hops onto the roof, and walks across the peak. Sitting above a check valve taped into the hole where the second floor roof meets the first floor's peak, he pulls it out, tosses it to the ground, and cuts away the tape that was holding it in place.
"What do you need up there?" Wagenbach calls from the ground.
"A piece of clay metal, the clips, and the gun," Greg says.
Wagenbach, large pair of scissors, thin piece of metal, and caulk gun in hand, climbs up the ladder and gives them, one at a time, to Greg. The check valve leaves a gaping hole. Before they put the check valve in, the gap extended 6 inches long, about three-quarters of an inch wide. Greg cuts the metal, folds it in half to match the incline of the roof, and taps it into place, fitting along the roofline and the shingles. "It's not going anywhere," he says, and climbs down.
As a kid, Frank worked with his family's sheet metal and roofing company and learned about bats from working on buildings. Now his three sons, including Greg, have worked with him at Bat Masters. For a while, Frick was the only bat excluder in the area, but then others came out of the woodwork. Now, says Frick, "any guy with a truck is a bat man." For Frick, bat exclusion is all about sealing the outside of a house, not getting the bats. "You don't need to be a biologist to do this," he says, watching Greg standing on the ladder two floors above him, "you just need to be great at working on a structure."
Another check valve sits above the garage roof. Greg climbs onto the roof, pulling a roof board behind him so he can sit and kneel without sliding off. He pulls out the check valve while Wagenbach stands guard. Greg cuts a small piece of metal to fit under the eave. A white cloth hangs out of his back pocket and waves in the breeze. The metal cut, Greg slides it under the edge of the roof and nails it in place.
"Caulk," Greg calls to Wagenbach who retrieves the gun and tosses it up to Greg. Caulking finished, Greg seals the metal in place and climbs off of the roof, holding two nails in his teeth. There are more gaps to be filled in the front of the house. Greg props the ladder near the front door, and climbs up. In a month or so, when they're in the neighborhood again, they'll come back to check on their work.
Still, all the caulk in the world won't stop bats. As territorial as the rest of us mammals, they're not about to be controlled. "Nature," says Frick, "does what nature wants to do."Samantha Cleaver is a freelance writer. Send comments to firstname.lastname@example.org