BAR HARBOR – Although the cranberry sauce served at Thanksgiving dinner may come sliced in perfect concentric circles and the turkey may be fresh from the grocery store freezer, a walk on the trails of Mount Desert Island will show that the tart berries still grow underfoot in the state and wild turkeys fly overhead.

An educational hike through Acadia National Park held Saturday will give the natural history of Thanksgiving, Lynn Havsall, manager of the Dorr Museum of Natural History at the College of the Atlantic, said Wednesday.

Though the sharing of treats is part of the day’s agenda, Havsall hopes that participants will leave having learned more about Maine’s three native types of cranberries and about the wild turkey’s demise and resurgence in the state.

“It’s not going to be so much gathering as a nature walk,” she said. “It’ll be nice to get in the park and walk around and work up an appetite for that Thanksgiving dinner.”

Maine is home to the commercially grown American cranberry and mossberry, a small cranberry that shares a genus with the blueberry and lingonberries, or lowbush cranberries.

Lingonberries are a circumboreal plant, or one that grows all around the northern hemisphere. They are popular in Scandinavia and Alaska, she said.

“It tastes very much like cranberries,” Havsall said. “All cranberries taste better after they’ve been hit by a frost, and we’ve had several frosts.”

Cranberries, a good source of vitamin C, were used for dyes by Maine’s American Indian tribes.

“Settlers were introduced by the Native American tribes to the cranberries,” she said. “Cranberries probably saved a lot of early settlers. The Indians knew it was a good food … and protected against scurvy.”

Turkeys are the undisputed star of the Thanksgiving table, but their popularity almost did the wild birds in.

“Massive, indiscriminate hunting really cut back on the species,” she said. “They used to be really abundant all across the Midwest and in New England.”

Wild turkeys scratch the ground for bugs, acorns and seeds, travel in gender-differentiated packs and are among the only birds in North America to be domesticated, she said.

“If Benjamin Franklin had had his way, the turkey would been our national bird,” Havsall said. “Maybe we’ll luck out and see some, or hear some.”

The free walk begins at 1 p.m. Saturday at the Dorr Museum at the College of the Atlantic. Call 288-5395 to register.