Nobody will be knocking on doors as they conduct an annual census this weekend.

Rather, they’ll be peering into backyards and wilder areas as they compile a snapshot of the North American bird population. And anyone with an interest in birding, or those who want to fight cabin fever, can participate.

A local event offering “looking tips” for novice counters as well as a refresher course for more experienced birders is set for Saturday during the the Great Backyard Bird Count at Thorn Creek Woods Nature Center in Park Forest.

The Beginning Birding for All event starts at 9 a.m. and will feature more than just tips for birders, according to Judy Dolan Mendelson, chairwoman of the Thorn Creek Management Commission.

“We really are promoting this open house as all things birds,” Mendelson said.

The bird count is part of the Audubon Society and Cornell Lab of Ornithology’s nationwide survey. No expertise is needed to participate in the count, Mendelson said, just a willingness to watch for and count birds for at least 15 minutes and report the findings to birdcount.org.

Among the Thorn Creek activities are a two-hour hike and hour-long bird watching session from a special viewing area. Bird viewing takes place inside a centuries-old church with windows that look out on an assortment of bird feeders.

There are more than 3 miles of trails in the 985 acres of woodland and wetland areas in the preserve, which make it an optimal place to see the varied species Mendelson characterizes as “winter residents.”

Winter months are prime time for bird watchers as the preserve attracts species of birds that Mendelson calls as “winter residents.” The hike begins at 9 a.m. and indoor viewing starts at 11 a.m.

April Richards, a naturalist at the nature center, said 151 species were spotted at the preserve in a recent count.

The more common woodpeckers, blue jays and cardinals are spotted frequently on the property. Nocturnal birds such as the barred owl and great horned owl are common to the nature preserve as well, she said.

“It is not at all unusual to hear an owl,” Richards said, “but owls are very difficult to see at any season.”

Birds considered rare have been seen on the property, including a sandhill crane resting in a wetland, she said.

Saturday’s open house will offer the opportunity to learn the distinctions among the species, Mendelson said. Experts will be on hand to offer tips on how identify birds by size, behavior and color patches.

Besides being fun and a way to get outside in the winter, the Great Backyard Bird Count, taking place Friday through Monday , is a way for area residents to contribute to an international scientific effort.

“This is a way to count casually and contribute to a census of birds so we can view trends,” Mendelson said. “The data is of great importance as it tells the whereabouts of bird species.”

Nature center volunteer David Schmidt said he wanted to build his “bird background” so he is taking part in classes at the center.

“I have learned a lot about birds, like recognizing the calls,” he said.

His wife, Vicki, is a bird enthusiast with nearly a dozen feeders in their backyard in Monee. The couple said the Cooper’s hawk is a common sight in their yard. One sighting they are hoping for is the courtship dance of the American woodcock.

Vicki Schmidt has taken part in the Great Backyard Bird Count in the past and plans to do so again by recording the birds she spots in her own yard.

More information at 708-747-6320. Thorn Creek Woods Nature Center is located at 247 Monee Road in Park Forest.

Barbara Dargis is a freelance reporter for the Daily Southtown.