A fly-by-night fascination.

Byline: Scott Maben The Register-Guard

Hissing and clicking, the bat sinks its teeth into Shonene Scott's skin.

The Portland State University graduate student barely notices. Besides, she's had her pre-exposure rabies vaccination.

"I usually let them just gnaw away on my hand," Scott said. "It doesn't break the skin, and I guess I deserve it."

But it makes it difficult to examine the tiny mammal, so she blows on its furry head to distract it. The bat lets go, and Scott continues taking its measurements as a group of observers crowd around in the dark woods north of Springfield.

They might have been mistaken for an "X-Files"-like satanic cult huddled under the stars if not for the high-tech gadgetry and scientific purpose of the late-night outing, a highlight of a bat conservation workshop this week in Eugene.

More than 50 wildlife biologists and forest managers from the Northwest convened to learn how bats use forest habitat, such as roosting in clusters under the bark of big trees. They also got to see the latest advances in acoustical monitoring and other technology to detect and identify bats.

The meeting, sponsored by Bat Conservation International of Austin, Texas, also gave bat experts the chance to cast the elusive and often feared mammal in a positive light.

"Bats are more often misunderstood than understood, even in the world of biology," said Pat Ormsbee, Eugene-based bat specialist for the Pacific Northwest region of the U.S. Forest Service. "They are not all that frightening, and they keep to themselves. They rarely interface with people."

But as with wildlife everywhere, bats face an uncertain future due to loss of habitat.

More than half of the 48 species of bats in the United States are in severe decline or already listed as endangered, and worldwide bat populations are falling, largely due to clearing of tropical rainforests, according to Bat Conservation International, a nonprofit advocacy group.

Bats also suffer as a result of insecticide spraying and intrusions on their colonies, careless cave explorers and rock climbers, for instance, who disrupt maternity roosts, Ormsbee said.

"I think it's very important to both educate people about the biology and complexity of the species as well as what they can actually do to further the conservation of the species group of bats," she said.

Protecting bat habitat

Learning how to protect the dead trees, caves and old mines that bats use in the Northwest was a thrust of this week's workshop, co-sponsored by The Wildlife Society, the Forest Service and the federal Bureau of Land Management.

One critical area of concern for managing bat habitat is how many tree snags to leave and where, Ormsbee said.

"When we create snags or leave snags in a unit that's been harvested, they don't stay up there forever," she said. "If your intention is to make sure we have snags into the future for bats and for cavity nesters such as pileated woodpeckers, you have to manage it out over time."

Another point of the meeting was to highlight the services bats perform for society. Nearly 1,000 kinds of bats account for almost a quarter of all mammal species around the world, and most are highly beneficial. They are the primary predators of night-flying insects that cost farmers and foresters billions of dollars annually, said Dan Taylor, director of the Bats and Forests Initiative for Bat Conservation International.

Bats also feed on mosquitoes and can play a role in reducing insect-borne diseases, such as the West Nile Virus. A single little brown bat can catch 1,200 mosquito-size insects in one hour.

Those are just some of the reasons why it's important for forest managers to ensure bats thrive in their native forest habitats, Taylor said.

Darca Morgan, a wildlife biologist for the Stanislaus National Forest near Sonora, Calif., attended the workshop because she's responsible for analyzing the effect of all federal actions on three sensitive species of bats in that forest.

"There's really very little information about these species, so I'm trying to learn as much as I can about them," Morgan said. "It's a little bit embarrassing how little we know about the bat."

She began thinking this week about the spots, including a pond she knows about in an oak woodland, where she's likely to find the Townsend's big-eared bat, red bat or pallid bat.

"I'm pretty excited," Morgan said. "All of a sudden your brain starts to look at habitat in a new way."

She said she hopes to employ some of the bat detection techniques she saw late Tuesday night when workshop participants gathered along a remote logging road in the McGowan Creek area northwest of Mohawk.

High-tech bat detection

It was a cool, clear night, which can keep the warm-blooded animals from flying. But the bat experts knew where to find them - around a small pond.

In addition to snapping up insects, American bats also drink - water, not blood - during their night forays. They swoop down and skim the surface of the pond, opening their mouth to scoop up some water.

PSU's Scott demonstrated a hand-held bat detector, a device that picks up a bat's high-frequency calls - the pings of its unique ability to use sonar to navigate and find prey. The sounds are translated for human ears as a series of chirps.

Scientists also use radio tags with exceptionally small transmitters and sophisticated night-vision equipment, similar to that used by the military, to track bats in flight.

But the latest innovation was on display on the hood of a car parked a few yards away. Joe Szewczak, a professor at Humboldt State University in Arcata, Calif., demonstrated a computer program that renders a graphic representation of bat calls. By comparing the picture of a bat call to a library of thousands of recorded calls, Szewczak can identify the species of a passing bat without ever seeing it.

Bat researchers are still building that archive of acoustic sounds, including from Oregon's 15 species. But they also are collecting morphologic and genetic data on bats.

Scott, who is researching the distribution of the Yuma myotis bat, showed how to make a positive identification of a species by measuring such features as ear length, forearm length and thumb length on Northwest bats, which typically are smaller than a human fist.

But to confirm an identity, Scott turned to the animal's genetic signature by taking a DNA sample from its wing. She demonstrated the technique on the field trip, in the light of a half-dozen head lamps, after the group caught five bats in the fine mesh of mist-nets strung across the pond.

Holding the wing down flat against a cutting board, she pressed a small, sharp punch against the thin membrane and turns it a few times. The bat was left with a tiny hole in its wing, which will heal in a few weeks, and the researcher was left with a 3-millimeter-wide biopsy.

For about $50, a DNA test on the sample will confirm the species. And the samples are archived at PSU for future research. The school's biology department now has more than 3,000 such samples from bats in the region, and researchers trade samples with other institutions across North America.

In conjunction with the Forest Service, PSU also is collecting DNA from bat feces, which is faster and easier than catching bats at night, said Jan Zinck, a biology professor at the school.

"We can put gutters under bridges and collect a whole summer's worth of guano," Zinck said.

Even old guano can reveal the genetic identity of the bats that left it.

"We can go back years and figure out which bats were in certain mines or caves," Zinck said.

Such techniques will help public agencies and private land managers know if a particular bat exists in an area as well as whether they have properly and thoroughly looked for the animals, Zinck said.

Part of the challenge is that bats don't always return to the same spot. They may choose from several roost sites in the day and several more at night, Zinck said.

"And we really don't know where they go in winter, and that's when the breeding occurs," she said. "So bats are much more complex and elusive than a lot of the other animals we manage for."

BAT TRIVIA

The common little brown bat of North America is the world's longest lived mammal for its size, with life spans sometimes exceeding 32 years.

Red bats that live in tree foliage throughout most of North America can withstand body temperatures as low as 23 degrees during winter hibernation.

The world's smallest mammal is the bumblebee bat of Thailand, weighing less than a penny.

Mexican free-tailed bats sometimes fly up to two miles high to feed or to catch tailwinds that carry them over long distances at speeds of more than 60 mph.

Fishing bats in tropical Latin America 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.

Bat droppings in caves support whole ecosystems of unique organisms, including bacteria useful in detoxifying wastes, improving detergents and producing gasohol and antibiotics.

An anticoagulant from vampire bat saliva may soon be used to treat human heart patients.

Less than one-half of 1 percent of bats contract rabies and those that do normally bite only in self defense and pose little threat to people who do not handle them.

- Bat Conservation International Inc. (www.batcon.org)

CAPTION(S):

Researchers meet around a table to take DNA samples from bat wings. Shonene Scott (right) is a Portland State University graduate student.