DALLAS -- Picture Big Bird. Now picture Big Bird careening toward your oncoming car at 30 miles an hour.

"It's not so funny when Big Bird is an emu and he's coming at you," said Johnny Waldrip, chief deputy sheriff in Grayson County (Sherman), Texas. "When you've got a wild emu running down a major highway, you've got a problem."

He and other law enforcement officials said stray emus spooking horses, chasing cattle into fences, startling rural homeowners and sending cars swerving on backwoods roads have become common occurrences from the Houston suburbs to the Red River and in the rolling ranch country west of Fort Worth.

Authorities said the problem has escalated in the past year as beleaguered emu ranchers, lacking any market for what was once billed as a replacement for beef on America's dinner plates, have freed hundreds and possibly even thousands of birds they can't afford to feed.

"I think everybody's getting calls on 'em," said Lufkin animal control director Cathy Clark, executive secretary of the Texas Animal Control Association. "I know for counties here in East Texas, it's become pretty routine."

In one of the most publicized cases, authorities in Parker County, west of Fort Worth, had to auction 211 of the birds last week after a roundup. Following state stock laws, Parker County Sheriff Jay Brown had to keep the birds 18 days and then advertise in local newspapers before selling them.

Sheriff Brown said at least 100 more birds are still roaming from a 400-emu flock that wandered from a ranch on the county's northeast side last fall.

Before the roundup, Sheriff Brown said, dozens of dead emus were found across the countryside. Some had been struck by cars and trucks, though no one reported injuries or serious damage, he said.

The elderly owner of the ranch where the birds escaped told authorities that only 25 were his and that the others had been dumped there by other emu ranchers, Sheriff Brown said. The county managed to sell all the captured birds to buyers ranging from emu growers to a woman with a petting zoo and a few people who wanted to eat them -- but they brought only $2 to $4 each, a fraction of the estimated $4,000 spent to house and feed them.

Officials from other parts of the state said Parker County was lucky to get anything.

"I had one that brought $2, but that's because it was little and it was cute," said Chief Deputy Waldrip of Grayson County. "Sometimes, we have a hard time giving them away."

It's a long way from the emu craze of the early 1990s, when a productive breeding pair fetched $50,000 or more.

Those Texas-sized prices and promoters' heady promises that low-cholesterol emu meat would become a grocery-store staple convinced thousands of Texans to jump into the fledgling industry.

In 1994, just before the market crashed, one study predicted that 2.5 million of the gangly, flightless Australian imports would be raised nationwide by 1998. Texas promoters boasted that half those birds would be Texans.

Then the emu bubble burst.

Within weeks, back-yard ranchers and big operators alike were stuck with birds they couldn't sell and feed bills of at least $100 a year per bird.

At least some stopped feeding their emus. In Lufkin, authorities responding to an animal cruelty complaint last March found 30 dead birds and 69 starving, Clark said. They later were told the flock originally had numbered 400, and its owner had more than $100,000 sunk into the operation, she said. A similar starvation case was discovered last summer in Navarro County, near Corsicana, Texas.

Other frustrated ranchers began killing emus. An elderly Parker County man was briefly investigated last summer after he used his shotgun to kill 64 of his 76 birds.

Some ranchers simply opened their emu pens and hoped their worthless birds would become someone else's problem.

That someone else, said authorities across Texas, is the state's sheriff's departments and animal control officers.

Just how big is the problem? Big enough to have become a regular rural annoyance, authorities said. Its full extent is anybody's guess, however, because no one knows how many Texas emus there are.

Texas Emu Association president Tom Thomason said he has no accurate population figures, but he doesn't dispute an estimate from one of his board members that about 300,000 birds are scattered on farms and ranches statewide. Thomason said about 3,000 Texans are still raising emus, and Texas is thought to have more than half the nation's emu population.

Law enforcement authorities said they know firsthand that a lot of those birds are on the loose. Though no serious emu-related accidents have been reported around the state, the birds have become a regular headache for rural law enforcement.

In Johnson County, near Cleburne, sheriff's deputies said they rounded up at least 50 last year.

In Grayson County, near Sherman on the Oklahoma-Texas border, authorities finally had to hire an official emu wrangler last summer.

"We sent out our cowboys after the first emu, and that emu whipped our cowboys pretty bad," Chief Deputy Waldrip said. "The cowboys said, 'We quit.' We realized right quick we weren't set up to deal with this."

Although normally docile, dim-witted and shy, according to McCartney and other emu experts, the birds can be dangerous when cornered. Their pipe-stem legs pack a mean kick against anything standing in front of them -- and each of their six toes is tipped with long, curved talons. A healthy adult bird stands up to six feet tall and weighs up to 100 pounds.

Emus run up to 30 mph, can jump four or five feet into the air from a standing position, and stretch themselves up to seven feet or more when frightened. On the loose, they terrify even the most unflappable cow ponies and can easily outmaneuver the few that are not afraid to approach them, emu experts said.

"It's kind of comical to watch a couple of uniformed deputies try to corral one. It gets pretty exciting," said Otto of Fort Bend County. "If you're in front of them they can drop kick you real quick, and with those claws they can flat tear up a pair of Wrangler jeans."

A few tangles with emus have persuaded some counties' officials to let the birds keep roaming unless they pose a road hazard or other serious problem.

Trinity County authorities quit trying to capture the birds last year after one sheriff's deputy was slashed badly enough to require stitches and a second deputy, responding to a complaint about emu spooking cattle, ended up being chased himself.

Trinity County Chief Deputy Richard Steptoe said the embarrassed deputy finally had to shoot the bird to keep it from attacking him.