The dung was actually thawing him out! He lay there all warm and happy, and soon began to sing for joy.
A passing cat heard the bird singing and came to investigate.
Following the sound, the cat discovered the bird under the pile of cow dung, and promptly dug him out and ate him.
Morals of this story
(1) Not everyone who shits on you is your enemy.
(2) Not everyone who gets you out of shit is your friend.
(3) And when you're in deep shit, it's best to keep your mouth shut!