John Tagliabue / New York Times News Service

COPENHAGEN, Denmark — Mikael le Dous has it in for bikers.

Le Dous, 56, a power plant engineer, rides a bike himself, as do his children, although he also has a car. He just wishes bikers would behave.

“We call cyclists the plague of the pavement,” he said.

Le Dous, a bearded, animated man, doesn’t just grump about delinquent bikers. As the head of the Danish Pedestrian Association, which he founded six years ago, he has dedicated his spare time to doing something about them.

Armed with a digital camera and a video-recording device mounted on the dashboard of his car, he photographs bikers who ignore traffic lights, go up one-way streets the wrong way or plow through pedestrian areas without dismounting, gathering material to present to the authorities to argue for stricter surveillance of cyclists.

Sometimes, he says, the results of biker misbehavior can be fatal.

“It happens occasionally that you’ll have an older woman, not hit but surprised and frightened by a bike so that she falls and maybe even dies,” he said. “Then they say, ‘Is the cyclist to blame because she’s an old hag?’ ”

In a nation dedicated to bicycling, however, le Dous has been fighting an uphill battle. The association now has only about 160 members, with a meager annual budget of a little over $2,000. But the focus of their annoyance is clear.

“I cycle a lot. We don’t mind cyclists,” le Dous said over coffee on a recent afternoon. “We mind people who don’t respect the law.”

Andreas Rohl thinks he has seen the future and is convinced that it moves on two wheels. Over at the city’s immense neo-medieval town hall, he heads a strikingly successful program to make bicycles the dominant means of transportation. Every day, 55 percent of Copenhageners travel to work or school on a bike, although last year, he admits, the number sagged a bit because of a severe winter. Why so many bikes? Simple, he says: “Because it’s easy; it’s an easy way to get around.”

A flip side to bike lanes

Broad bike lanes abound in the Danish capital, population 1.2 million, and bikers fill them. Some thoroughfares, including bridges over the harbor, are exclusively for bikes. On some days, Rohl boasts, as many as 36,000 bikers swarm through the Norrebrigade, one of the streets leading to the city center that now consists of wide bike paths in both directions, squeezing narrow lanes for cars and buses.

Ullaliv Friis, 66, a retired city official who is the pedestrian association’s managing director, says that she appreciates all this, but that there is a flip side. Many retirees and older people live in the row houses in a suburb north of the city center where she makes her home. The sidewalks have become risky for them, she says, because of stray cyclists. “The cyclist has taken over everything,” she said.

Le Dous looks enviously at a group he sometimes considers his nemesis, the Danish Cyclist Federation. Founded in 1905 and boasting 17,000 members around the country, the federation wields the enormous clout in Denmark on matters of traffic that automobile associations have elsewhere.

With 25 employees in its main office, the federation has grown in recent years to make the bike an exportable item, not just physical bicycles and biking equipment but also consulting and advice for cities elsewhere seeking to become more biker friendly. In 2009, the federation cited Mayor Michael Bloomberg for his effort to promote biking in New York (even as angry groups of New Yorkers protested the removal of bike lanes along Bedford Avenue in Brooklyn).

Frits Bredal, 46, a former television journalist who is the federation’s spokesman, said it was aware of anger over bikers.

“There is resistance from people who are frustrated by the fact that cities are flooded with bicycles,” he said. “I am a car driver, I am also a cyclist,” he said. “If I bring my car into the city, I’m invariably frustrated.”

Yet he adds: “Bicycles are not just nice and cute; they will be, and should be, a central part of Danish transport policy, local and national.”

Bike safety has improved recently, he said, thanks to a range of measures, including wider bike paths and programs to alert bikers to the need for discipline. “Last year, we had the lowest number of traffic accidents ever, including the lowest number of fatalities involving bicycles ever,” he said. In 2010, the number of seriously injured cyclists dropped to 92, including three fatalities, compared with 252 seriously injured only five years earlier.

Like many in Copenhagen, Natalia Privalova, 37, an office manager, has two bikes, including a cargo bike with a wooden platform in front to transport her children. Cyclists respect pedestrians, she said, then tempered the assertion by adding, “when they follow the rules.”

“Of course,” she said, “rush hour is another story.”