This is a newspaper article of some length, discussing use of taped calls to 
bring birds into view. It should be of interest to us all. 
Jim Williams
Wayzata

By Sandi Doughton
The Seattle Times

SEATTLE — On a spring morning in North Seattle, a chestnut-backed chickadee — 
let's call him Chuck — was taking care of business when he heard an alarming 
sound: the high-pitched song of another male.

Chuck swooped in to investigate. Perched in a hemlock, he cocked his head, 
listening for the intruder. Hearing no repeat, he voiced his "chick-a-dee-dee" 
challenge. He then flew off, paying scant attention to the gray-haired man 
holding an iPod-speaker combination the size of a coffee mug.
"I promise I'll never do this to you again," said Dennis Paulson, a veteran 
birder and director emeritus of the Slater Museum of Natural History in Tacoma, 
Wash.

Paulson was demonstrating a technique that's hatched a flap among 
bird-watchers: the use of recorded calls to flush out species for better 
viewing and photography.

These being folks who love nothing more than tramping around with binoculars, 
the sparring is mostly polite. It's a given that no one wants to harm a feather 
on a sparrow's head. But the question is whether being summoned by a phantom 
rival may, in some cases, actually put birds at risk.

"It stresses the birds, I wouldn't deny that for a minute," Paulson said. "But 
as far as I know, it's a very, very short-term stress." His personal rule is to 
use "playback" rarely and only where birds aren't likely to ever encounter 
recorded song again — deep in the woods or, just this once, his forested yard.

But for many other birders, playback has become a tool of first resort, thanks 
to the proliferation of smartphones and apps that can crank out tunes from 
every species on the planet. At the same time, birders share unusual sightings 
and hot spots via the Internet, which can mean the same birds are blasted over 
and over.

"It has gotten much more common," said Dr. Jack Stephens, president of the 
Washington Ornithological Society. He recalls the days when only the most 
expert birders bothered to cart bulky tape players into the field. "Now, you 
see people get out of a car and the first thing they do is pull out a recording 
and start to play it on a loop."

Like most birders, Stephens is middle-of-the-road on playback. He cringes at 
overuse. But, after 45 minutes of fruitless scanning on a Texas trip, a song 
snippet earned him a glimpse of a Swainson's warbler, one of North America's 
most secretive species.

While delightful to our ears, singing is serious for birds. Males pour their 
hearts out to impress the ladies. They trill to proclaim territory and keep 
other males away. Every strange song — whether from another bird or an iPhone — 
registers as a threat.
 
"That's why it works," said Sam Wasser, director of the University of 
Washington's Center for Conservation Biology. "The male is going: 'Oh, my god! 
There's another bird in my territory.'" The trickery is most effective during 
breeding season.

When the sought-after bird pops out, birders can snap pictures and tick off a 
box on their life lists. But the consequences to the bird can include 
heart-pumping anxiety, exposure to predators and an undefended nest and mate.

"I've seen woodpeckers respond to playback from birders ... and a sharp-shinned 
hawk comes and takes that bird out," said Martyn Stewart, a Seattle-based 
wildlife recording expert.

Stewart is "dead set against" the use of playback to lure birds — yet many apps 
and song libraries include his recordings. "It's ironic ... but I'm really 
instrumental in it," he said.

With 30-plus years of experience, Stewart easily can detect the difference 
between a relaxed bird and one responding to a threat. "You can hear the stress 
in their voice," he said. "Birders will say there's no harm done, but that's 
because they want to justify putting a bird on their list."
Federal biologists recently scaled back the use of recordings in spotted-owl 
surveys after it became clear that birds who "Whoo"-ed in reply were subject to 
attack by more aggressive barred owls.

One reason birders are so split on the use of playback is that there's little 
evidence pro or con. But a handful of studies suggest the practice is not 
entirely innocuous.

Ordinary life already is tough for birds, especially during breeding season, 
said University of Washington biologist Eliot Brenowitz, who studies brain 
wiring and bird song. In some species, males become accustomed to the voices of 
their neighbors, which makes them more likely to be alarmed by an unfamiliar, 
recorded call, he said.

University of Washington professor emeritus John Wingfield found testosterone 
levels increased up to tenfold in male song sparrows confronted with taped 
songs. They remained revved up for one to two days. "These males will continue 
to spontaneously sing and patrol their territory," Wingfield said. "They get 
very aggressive and attack other birds." And they were distracted from parental 
duties, such as feeding chicks.
Elevated testosterone also may suppress birds' immune systems, though that link 
is unproved, he said.

Wingfield's years of field research helped persuade him to give up the use of 
playback in his recreational birding. Daniel Mennill, who discovered playback 
can have romantic fallout for male birds, still makes judicious use of the 
technique.

"In moderation, I don't think it's going to have negative effects," said the 
University of Windsor, Ontario, biologist.

When Mennill and his colleagues bombarded male black-capped chickadees with 
recorded calls to simulate an aggressive rival, they discovered females were 
listening, too. Lady birds whose mates came out on the losing end of the 
singing contests were much more likely to engage in "extramarital" flings. 
Other males also took advantage, encroaching on the turf of neighbors who 
appeared weak.

"There's a message in there for bird-watchers," Mennill said. "It's conceivable 
that (aggressive use of playback) could influence the bird's reproductive 
output for that year."

———
Recorded birdcalls are banned in some parks and refuges, including the national 
parks. To many old-school birders, it's just considered lazy. But curmudgeons 
aside, playback is here to stay, said ornithologist, artist and bird-guide 
author David Sibley

After creating a bird-identification app, Sibley drew up a list of suggested 
guidelines for the proper use of recorded calls. Chief among them is to never 
target threatened or endangered species, to use only short snippets of song and 
to stop after a few minutes.

If the instant gratification that playback can provide draws more people to 
bird-watching and environmentalism, many birders argue that's a good thing. In 
some cases, luring a bird into the open with playback can be less disruptive 
than a group of people stomping around in the bushes, Sibley said. Even birders 
who just sit still can be disruptive. "You might end up sitting near a nest."

When alone, Sibley prefers to watch birds behaving naturally. He says he pulls 
out the handheld sound system only when he's leading field trips and doesn't 
want to disappoint.

"I find it sort of distracting," he said. "I end up spending more time messing 
around with the device, starting and stopping, setting the volume, and less 
time actually looking at birds."

(c) 2011, The Seattle Times.
Visit The Seattle Times Extra on the World Wide Web at 
http://www.seattletimes.com/.
Distributed by McClatchy-Tribune Information Services.


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