As quick as the call for volunteers went out to monitor owls in the wee hours of the morning, the routes were nearly filled throughout the state.

As of Thursday, only four routes remained unclaimed: Eustis, Farmington, Mercer and Raymond.

The Maine Audubon Society has been conducting the Maine Owl Monitoring Program for several years now in a partnership with the Maine Department of Inland Fisheries and Wildlife.

People who volunteer are considered citizen scientists and are given a compact disc and training material to learn the nine owl species they may hear during the surveys, which begin at 1 a.m. and end by 5 a.m.

“The most striking thing about it is how many people want to do it,” said Susan Gallo, a Maine Audubon Society wildlife biologist and coordinator of the owl monitoring program. “I have been swamped with e-mails and phone calls since the press release went out.”

More than 135 volunteers took part in the survey last year on 70 road routes and heard 231 barred owls, 55 great horned owls, 100 northern saw-whet owls, one eastern screech owl, one long-eared owl, two short-eared owls and four owls they couldn’t identify, according to the Maine Audubon field season summary.

Most routes had at least one owl detected during the 2006 survey, an improvement over 2005 and comparable to 2004.

At each stop, volunteers play a 13-minute CD, which has several minutes of silence along with hooting calls of the long-eared owl, barred owl and great-horned owls.

The total number of owls detected in 2006 is higher for all species compared to 2005, the society’s summary states. This is likely due to the lack of snow cover in 2006 that would have made prey more available.

The long-eared owl is a species biologists would like to learn more information about, Gallo said.

They are listed as a special concern in the state.

That is why this year’s project is playing the call of the uncommon long-eared owl instead of the more common northern saw-whet owl, so that biologists can learn more about where the long-eared owl lives and its habitat, Gallo said.

“Long-eared owls are very uncommon; that would explain why we know almost nothing about them,” Gallo said.

Biologists expect that the barred and great horned owls are more common, she said, and they’re trying to determine if they really are.

There’s a real hot spot in Central Maine where owls are, Gallo said. It’s a little pocket east of Route 95 in Waldo County that includes the towns of Union and Liberty

Volunteers involved in the project will make 10 stops along their road routes.

Citizen scientists will log information about what owls they heard, weather conditions and temperature among other data on a sheet and send it to Gallo.

The surveys are helping biologists to get an idea about how many owls live in the state, which is not an easy calculation because owls are active at night and breed during the winter, Gallo said.

Most bird surveys are conducted later in the early morning hours, she said.

The group is trying to determine how common species of owls are in Maine and if there are places that are expected to have owls have them or are missing them and to get information on them. The counts are conducted any night up until April 15.