The Eager Beaver is a 1946 Merrie Melodies short directed by Chuck Jones.
Plot[]
Beavers are "damning" a river! Another group of beavers are working on a big dam, with an obnoxious foreman who can't make up his mind on how to position the logs.
All the beavers are hard at work when Eager Beaver arrives on the scene, and while he's ready for action, he just can't seem to find a tree that nobody else has beaten him to. There's either somebody else in the way or he's in the way of somebody else. After nearly chopping our hero by accident, a tall, burly fellow points to a huge tree at the top of a mountain and yells "Why dontcha chop THAT tree down?!" Eager immediately sets to work. He soon finds that it's not as easy a job as it looks; the tree breaks his axe and explosives do nothing but blow up some of the rock the tree is growing in.
Meanwhile, a bird tells the other beavers to hurry up with the dam because a flood is approaching. They hurry it up, but when there's one log left, the foreman's obsession with precision wastes valuable time. Unaware of any trouble, Eager finally chops the tree down using a termite, and finds himself and the tree falling down into the canyon below. The flood sweeps the beaver and the tree downstream, the tree ultimately filling the gap in the crew's dam. The beavers cheer and give Eager a hero's welcome, and the foreman is crushed by his own falling log.