Prey (2011)

Synopsis: One night, several deer inexplicably hurl themselves against the electric fence of a farm. Discovering deep bites on the animals bodies, the farmer and visiting family members (who have gathered for a tense reunion) penetrate deep into the surrounding forest. They carry guns, expecting to encounter wild predators, but what they are bewildered to find is an environment ravaged by a mysterious evil force. And as the sun slowly sinks away, howling resounds through the forest. The hunters have become prey! This modern-day horror film blends elements of The Descent, Jaws and Deliverance into an original picture of human nature scarier than the darkest woods.     Source: Amazon.com