It is very important not to disturb hibernating bats because they can lose valuable energy reserves and die. All bats can see. It is a very sophisticated sonar system inaudible to the human ear. The bat emits signals that go in waves. When the sound-waves strike an object, they return to the bat's ear as echoes.
Bats suck our blood.
There are only three species of bats that feed on blood. Vampire bats live in Mexico and Central and South America. There are no vampire bats in the United States. They lap, not suck, small amounts of blood from tiny wounds they make in wild and farm animals. They rarely attempt to feed on humans because human blood is not palatable to them.