HARVARD — The Harvard PTA provided the funding for “Eyes on Owls,” an eye-opening lecture and slide program and live owl demonstration presented by naturalist Marcia Wilson in a second grade classroom at the elementary school last week.

Pupils from the four second grade classrooms participated in the program, which highlighted a study section the class has just completed on owls.

Wilson, a self-described second-generation owl lady, dates her fascination for these birds back to her childhood. Her mother gave live owl programs at the local science center. Both of her parents were bird watchers who kept multiple feeders at home. Wilson started bird watching at the age of 6 and belonged to Mass. Audubon Society’s Chipmunk Club. Now, birds are her business as well as her passion.

Wilson, who wears clothing and jewelry almost as owl-centric as her presentation, brought six owls to HES, including four rescued owls with disabilities that prevent them from living in the wild, like the owls at her home. Two exotic exceptions in her traveling entourage were six-month-old owls native to Costa Rica, who were born in the U.S.

The presentation, which included habits and habitat, distinctive features, owl-spotting tips and live introductions, focused on three owls common to New England: the barred owl, great horned owl and screech owl.

The pupils, who have been studying owls, were versed in owl vocabulary. They knew, for example, that claws are called talons, varied shades of brown feather colors that match tree bark are called camouflage and that saucer-shaped facial discs include not only the owl’s big eyes but hidden ears as well. Those strong legs, feet and talons are the “business end” of the owl, Wilson said, and along with acute eyesight and hearing, are tools the owl uses to capture its prey.

Noting that she had recently found fish bones in the pellets of a great horned owl, which is not a water bird likely to go fishing, Wilson speculated that the owl had picked the carcass of a fish found on the ice of a lake or pond.

Wilson said owl pellets are not “poop,” but discard raised through the digestive system and expectorated via the beak, like the way a cat coughs up a hairball. She was hopeful that an owl would hawk up a pellet to examine, but none did. She also warned her audience to look out for whitewash, which owls drop on the fly. These owls were tethered and did not fly free, but they flapped long wings impressively and looked ready to take off. Fortunately, Laurie Johnson of the PTA was on whitewash patrol, she said.

Owls don’t make nests of their own but reclaim the abandoned nests of other predators, so scout for signs under trees as you walk quietly through the woods, Wilson advised. Another way to spot an owl is by listening, she said, demonstrating the variety of calls and clicks and hoot combinations that identify a particular owl. Owls sleep during the day and hunt at night, so early morning and twilight are good times to hear them, she said.

She also cautioned that baby owls should not be taken away if found on the ground, as some well-meaning rescuers have done. Some of the owls at her home came from people who did that, she said, and as a result, the bird became “imprinted” on humans and could no longer survive in the wild. If you see a baby owl on the ground, put it back on the branch or into the nest if possible. Otherwise, leave the owl alone.

“The parents are probably close by,” Wilson said.

Injured owls are different. They need to be rescued. One of the owls — a lively great horned owl she brought to the school — was found on a N.H. roadside several years ago after having been hit by a car, she said. The Wilsons acquired the owl after it was treated at a wildlife rehab facility, where it was determined the owl could not be released back into the wild.

“This owl could live into his 30s or 40s, “ Wilson said.