Thrush

A thrush is a slender, small to medium-sized bird known for its harmonious song.
== History ==
The thrush is said to have belonged to an ancient breed known by Thorin's ancestors. The Men of Dale were able to understand the language of the bird, and they served the men as messengers. Bilbo was skeptical that any of the Lakemen still spoke the thrush language, but was proven wrong when the bird told Bard the Bowman of Smaug's only weak spot, thus enabling Bard to kill the dragon.
== Portrayal in adaptations ==
A thrush appears at the end of the film, The Hobbit: An Unexpected Journey, flying towards the Lonely Mountain. It begins tapping a snail shell against the side of the mountain and the echoing of the tapping is heard all the way into the treasure room, causing Smaug to awaken.
The thrush is seen again outside of the Lonely Mountain in The Hobbit: The Desolation of Smaug during the secret passage's opening.