If you're hiking along the Natchez Trace National Scenic Trail this spring, be alert for wild hogs/NPS file photo of Natchez Trace National Scenic Trail along the Potkopinu section

You know you should be alert for grizzly bears in the Northern Rockies, and sharks in the surf are a concern, but have you ever worried about hogs while hiking in a national park?

Great Smoky Mountains National Park in North Carolina and Tennessee does have wild hogs, but the latest alert for hikers to watch for rowdy boars comes from the Natchez Trace Parkway, where officials and visitors have witnessed increased feral hog activity from milepost 0-40. The number of feral hogs is on the rise statewide and directly correlates to more sightings along the Parkway, according to the National Park Service.

Like many wildlife species, feral hogs will be most active at dawn and dusk.

“Feral hogs have great senses of hearing and smell. They typically avoid contact with humans, but in the spring females may exhibit aggressive behavior to protect their young,” says the Parkway's chief of resource management, Dr. Lisa McInnis. “The Parkway is especially vulnerable to feral hogs because of the long, linear nature of the habitat. This year, feral hogs are causing significant damage to the agricultural fields and the mowline of the Parkway from their rooting activity.”

Caution is encouraged this spring when hiking or biking near the southern end of the Parkway. Visitors should be aware of their surroundings and avoid walking through dense undergrowth where feral hogs may be encountered. If a feral hog is seen, do not approach it. Stop, stay calm, and back away slowly and diagonally to avoid an encounter and give the animal a wide berth, or wait for it to leave the area.

If the animal is aggressive, vacate the area immediately by climbing a tree or other nearby structure. Most experts recommend the diagonal side step escape to avoid charging animals or use a calm voice to deter the animal.