If you're a property owner or manager, you don't really want to see one of Dave Cheaney's guys park a company truck across from your place. He runs a Ballard business called National Bird Control, which does exactly what its name states...Those pigeons causing havoc across the street may just decide to make your property their new home...He understands why all this might be upsetting. "It's what I call the `cute factor.' They're cute little birds," says Cheaney. So Cheaney understands how his "last resort" solution to pest birds might be especially upsetting to some...Cheaney euphemistically calls the latter method a "mechanical extraction." The mechanical part comes from using a high-powered, compressed-gas Beeman-brand rifle with a scope. The manufacturer says it shoots pellets at a minimum of 950 feet per second. "We're not going to say we shoot pigeons. That sounds kind of heartless," he says. "You try to be politically correct...It is perfectly legal to shoot these birds, as long as local gun laws are followed. According to the state's Department of Fish and Wildlife, these three invasive species "may be killed at any time." Introduced by well-meaning people to North America, these birds have gone on a population rampage. A 1903 book called "Birds of Ohio," says, "Without question the most deplorable event in the history of American ornithology was the introduction of the English Sparrow." The sparrows have been known to attack native bluebirds, for example, "leaving a blood-covered mother bluebird who fatally tried to protect her young."...If "mechanical extraction" of pigeons sounds a little reminiscent of military talk, well, Cheaney, 51, did spend six years in the Marine Corps...Border Patrol in Texas, and for the Snoqualmie Police Department, before answering an ad from a pest-control firm and gaining experience in that field. Eventually, in 1999, with $100 he had in savings and $500 borrowed from Dianna Forbes, now his wife and partner in the business, he started National Bird Control. His first job was for $3,000 to use netting to deal with pigeons that were nesting all over the recessed neon sign at Anthony's HomePort restaurant at Shilshole Bay. Now, his company of half-a-dozen people proudly claims clients that have included Costco, Safeway and Harborview Medical Center. Cheaney gets called when bird droppings make a sidewalk a slippery slog, or bacteria-laden particles from the droppings waft through air vents. Sometimes, Cheaney brings his 114-pound yellow lab, Sergeant, who is adept at running through a parking garage and catching a pigeon in his mouth but not killing it. There is an incentive for building owners to call a bird-control company. "We live in a very litigious society," says Cheaney. "Everybody tries to sue somebody." In 2009, for example, a New York City man ended up being awarded more than $6 million by a jury after he suffered spinal injuries slipping on pigeon droppings at a subway station. And, sometimes, National Bird Control gets called because the birds are just plain annoying, deciding to build nests right above bedroom windows in apartment complexes. Last week, one of the jobs consisted of going through all the rain gutters at such an apartment complex in Everett. The gutters had previously been covered with wire mesh by another company, but gaps had been left, and sparrows managed to get in. Using an articulated lift that could go 45 feet high, one of the technicians, Mark Norman, pulled out the nests, filling up a large plastic garbage sack. "Twigs, leaves, candy wrappers, feathers from bigger birds, grass...The nests were empty, says Norman, the hatching season being in the spring. But if he does find birds in the nests, the adults are let go to fly away...On an evening last week, the crew was in downtown Seattle, at Second and Seneca, at the Safeco Center. A couple of weeks ago, they had installed a 2-inch-wide electrified track system along the second- and third-floor ledges of the building. Pigeons had been hanging out at the ledges, their excrement bombarding the sidewalk and pedestrians below. The electrified tracks deliver a shock equivalent to touching a 12-volt car battery, says Cheaney. "It doesn't hurt them, but it's enough of a jolt so that they don't forget it anytime soon." Inside the building, office workers reported hearing popping sounds from the strips...Watching below, a woman who happened to walk by wants to make sure the pigeons won't be electrocuted...All the time, Cheaney has to weigh the public-relations aspects of controlling pest birds. Among his clients is one of the national hardware chains, for which he travels around the country...Instead, Cheaney uses soft "mist nets" hung from the rafters, which the sparrows fly into, and tumble down into pouches without being hurt. Such netting can work in a box store, but it's hard to use it in a parking garage, says Cheaney. There are too many nooks and crannies where a pigeon can fly around, and they also fly considerably slower than a sparrow and so see the netting and avoid it.At one box store, Cheaney and his crew caught 236 sparrows. "The health department had been threatening to close the store," he says...Plenty of other buildings with ledges for the pigeons to move to and relieve themselves with their acidic, corrosive droppings. Says Cheaney, "The fancier, the prettier architects try to make buildings, the birds are going, `Thank you.