OTTAWA - Police forces in some parts of the country say drivers are slowing down as the price of gasoline continues to rise.

It's a phenomenon that's catching the attention of radar gun-wielding traffic cops across North America. Natural Resources Canada recommends drivers stick to or below the posted speed limit to save on fuel. Studies have found increasing speed to 120 kilometres an hour from 100 can increase fuel consumption by 20 per cent, the department says.

But as drivers ease up on gas pedals, some are also using their brakes less - especially at stop signs.

"Absolutely, we have noticed a decrease in speed," says Sgt. Cam Woolley of the Ontario Provincial Police.

"We've also noticed a decrease in discretionary travel."

That's not to say there are no speeders.

But many Canadians, it seems, are changing their driving habits as the cost of a litre of gasoline soars to new heights. The average national price reached almost $1.40 per litre at gas pumps Friday, up from just over $1.08 in the first week of July a year ago, says

Provincial police in Ontario report drivers slowing down, especially on Canada's busiest highway, the 401.

There has also been an increase in some locations in complaints about people doing so-called "rolling stops."

"It seems to be up, where people aren't coming to a full stop" if they think they can save gas by not having to accelerate from a stopped position, said Woolley.

There are also fewer drivers on the road when the roads are wet, which could result in fewer weather-related automobile accidents, Woolley predicts.

"A lot of the summer travel is really weather sensitive now," he said.

"People that rent (cottages), or day-trippers, if the weather forecast isn't really good, they don't go."

More and more people are using carpooling lanes as well, he said.

In Nova Scotia, police are issuing just as many speeding tickets as they have in the past. But they're being issued more and more to habitual speeders, says Cpl. Joe Taplin, an RCMP spokesman in Halifax.

"People are slowing down," said Taplin.

"However, they are still getting people on the excess speeding. The overall mean speed is dropping, but you still have your hard-core speeders that are still continuing to speed."

It appears gasoline prices aren't having the same impact on traffic infractions in Alberta, where gasoline prices just this week rose above $1.30 per litre, on average, and are typically lower than in the rest of the country.

RCMP in Alberta say there has been no noticeable slowdown on the highways, or the number of tickets being issued.

Transportation experts and some law-enforcement professionals caution that it's too early to draw a direct link between driving speeds and pump prices.

But Woolley says he's convinced there is a correlation.

Police forces in Canada don't track or publish exact statistics on highway speeds. In the United States, however, some states that do keep records have also noticed speeds dropping.

Data from electronic monitoring of average speeds along some stretches of interstate highways show speeds were down in the first five months of 2008 in Tennessee, Virginia, Washington and Wisconsin.

And of 20 states that compile figures on citations issued by state troopers, the number of speeding tickets was down in 13 states, and up in seven from Jan. 1 through the end of May.

If reduced speeds are a positive effect of higher gasoline prices, there have been negative effects on drive habits as well.

Some people who used to speed, but who've slowed down, still insist on driving in the fast lane, says Woolley.

"The worst part of the fuel saving is there are some people who are changing their speed, but not their lane discipline," he said.

"They'll stay in the left lane of an expressway and do 90 kilometres an hour and make everybody behind angry."