Woodpeckers peck wood in order to get the insects hiding beneath the bark. Woodpeckers have an extremely acute hearing and are capable of hearing bugs crawling around under bark. If they don't hear them , theuy surely can feel the vibrations the insects create as they move about. Powerful muscles and a tough bill are necessary to produce the tremendous force needed to break through the bark. Besides, the woodpecker has strong, grasping feet that work together with the stiff tail feathers, allowing the bird to position itself for its strenous pecking. After the hole is drilled into the tree, it can't grab the bugs with the bill is the same size as the hole. What it does is that it inserts its long, sticky tongue, which is 3 times longer than its bill, into the hole to catch the insect, pull it out and eat.
BITS OF FACTS
A gila woodpecker escapes the heat of the desert by making a nest inside the giant saguaro cactus plant, which is the largest of all cacti The temperature inside is 30 degrees cooler