It may be a good time to revisit your jobsite security: More heavy equipment is stolen in July than any other month of the year, according to a new report from the National Equipment Register and National Insurance Crime Bureau.

The highest volumes of equipment theft typically occur during the peak construction months.

The summer months, when construction activity is usually in high gear, collectively made up for about one-third of all heavy equipment thefts last year, says the July 21 report.

During 2010, NICB received 13,374 reports of heavy equipment theft, valued at approximately $400 million. Last July, it received 1,493 reports, the highest month for the year, followed up closely by June and August. The lowest number of reported incidents came in December, at roughly 700.

About 19% of the reported stolen equipment last year was found. "Recovering stolen equipment and identifying the rightful owners remains a challenge," says Joe Wehrle, president and CEO of NICB.

The most frequently stolen pieces of equipment, says the study, were landscaping equipment, such as mowers. That category is followed by loaders, such as skid-steers, wheel loaders and loader-backhoes. The smaller the equipment, the more likely it is to be stolen, experts say.

Although frequency of theft has remained flat for the last few years, it remains the top insurance claim. Theft last year occurred most frequently in Texas, Florida, North Carolina, Georgia and South Carolina.

Which brands are most at risk? According to NER, the top-ten stolen marques in 2010 were John Deere, Kubota, Caterpillar, Bobcat, Case, Cub Cadet, International, New Holland, Ford and Takeuchi.

Fleet owners can reduce the risk by locking up machines, surrounding small iron with larger equipment, keeping up-to-date records of machine serial numbers and offering records to authorities when a theft occurs, experts say.