CHICAGO — Ever since he was laid off in March, Frank Beil has been on the lookout.

He keeps an eye out for cars moving slowly down the street or strangers walking along the sidewalk of his suburban Chicago neighborhood. He wonders about the times he answers the phone and the caller hangs up.

“You don’t know if that might be people staking you out, finding out if you’re home or not,” said the 71-year-old hospital chaplain from Glenview.

Beil is watching for burglars, and police nationwide credit him and those like him for one of the few bright spots of the recession: The number of home burglaries is falling in some cities and towns.

“With a lot more unemployed people, a lot more people are staying home, and they see more in their neighborhood,” said Sgt. Thomas Lasater, who supervises the burglary unit of the police department in St. Louis County, Mo., where authorities recorded a whopping 35 percent drop in burglaries during the first six months of 2009.

The trend is showing up in communities big and small.

In Minneapolis, the number of burglaries reported in roughly the first nine months of the year dropped more than 15 percent compared with the same period last year, and more than 25 percent compared with that period in 2007. In Boston, the 2,199 burglaries reported in roughly the first nine months of the year is 335 fewer than in the same period last year.

Aurora, a city of 170,000 outside Chicago, had 560 burglaries through the end of September, a 15.5 percent decrease from the same period last year. And in Shelby, N.C., a town of 21,000, the number of burglaries through August was 23, compared with 60 for the same time last year.

In many cities, other crimes including homicide, robbery and rape have been dropping for several years, according to FBI statistics. But burglary stands out because it was actually rising between 2007 and 2008, and experts expected that trend to continue as the recession dragged on and unemployment rose.

The phenomenon has surprised both police and crime researchers. “We were thinking, ’Here we go,”’ said Theo Glover, deputy police chief in Rockford, a struggling manufacturing community in Illinois that consistently has the state’s highest jobless rate, hitting 16.9 percent in August.

Instead, Rockford had 1,849 burglaries through mid-October, or more than 400 fewer than in the same period last year.

A national total of this year’s burglaries will not be available from the FBI until late next year, but experts said the anecdotal evidence from individual cities paints an unexpected picture.

Richard Rosenfeld, a sociologist at the University of Missouri-St. Louis who has studied crime trends, said rates typically rise during a recession, especially property crimes.

“We’ve seen that in every single recession in the U.S. at least since the ’50s,” he said. “I would have expected by now some upward movement in burglary numbers.”

The burglary rate has, in fact, climbed this year in some cities, including Houston, San Jose and Chicago. But in Chicago, the rate is climbing at a slower clip than it did last year.

In other places where burglary rates already were dropping, they are falling even faster. That includes Los Angeles, where the number of burglaries in the first three quarters of 2009 fell 6 percent, compared with 1 percent during the same period in 2008.

Some police believe the falling price of copper and other scrap metals — a target of burglars who strip the metal from vacant homes — may have contributed to the trend. But they say that alone would not explain why burglaries are dropping so steeply in so many places.

Phoenix police detective James Holmes believes his city’s 14 percent drop in burglaries in the first nine months of this year mostly reflects a stepped-up effort to target habitual burglars and expand neighborhood watch programs. But he said residents clearly are paying more attention, and more people are home to keep watch.

“We are getting a lot more calls of suspicious activities in our neighborhoods,” he said.