Dragons are fierce and deadly and generally steer clear of people. Cow milk speeds up a dragon's growth.  Their diet also consists of large mammals and big fish like sharks. They will eat humans if they are very hungry.  They are solitary and sometimes called wyrms or drakes. Dragons lay eggs like snakes. Baby dragons can fit in your hand and look like salamanders, but a little larger and not as colorful. As they grow they begin to speak and reason. Some are quite wise yet the majority are tricksters. Dragons sleep a lot and appear lazy, but are quite swift both on land and in the air when they are hunting. Good indicators that dragons are about are a thick, poisonous vapor in the air and water that stings the throat and skin of whoever touches it. Dragons contaminate everything they touch with poison.
* photo courtesy of Arthur Spiderwick's Field Guide