Humans and wolves are the beaver's predators.
beaver
To keep them safe from wolves and other predators
One wetland animal, the beaver survives by building a dam.
A beaver has a few ways to protect itself. Its first line of defense is, of course, to be well-hidden from predators. It has a good, hidden-from-view place to stay inside its dam. The dam is out in the water, and the beaver den is part of the dam. Very few predators know about the den inside the dam. And if they learn about the existence of the den, it's practically unreachable in the water. Some animals will swim out to the dam and try to get at the beavers there, but I don't think very many succeed. If a predator (let's say a bobcat is after our beaver) should get to the dam out in the water, they next have to break into the den from above. The beavers have sharp front teeth! (Strong enough and sharp enough to cut down trees!) They can discourage a bobcat from continuing to try to break into the dam. If a beaver should be caught out in the open by a bobcat, he can whack! that bobcat a mighty blow with his tail! Say the bobcat gets an opening, and grabs the beaver's tail. He starts dragging the beaver away, but the beaver fights back with his big front teeth, and his claws on the front legs! I think there would have to be several bobcats that can gang up on the beaver in order to win this fight! The beavers would help each other, too. If another beaver is near, he would help the first beaver get away, then join him.
a beaver holds its breath for as long as it can
Beavers are on the endangered species list because 200 years ago, man use to hunt beaver and they have so many predators and they can not move fast on land.
If you call someone an eager beaver it means they are busy/enthusiastic/keen in doing something. Just as beavers are when building their dam.
animal eat beaver?
They were used as building Dams, and when they pat their tail against the water that means they warn predator's away or to signal danger.
One wetland animal, the beaver survives by building a dam.
There is a new solution I came across that a company is working on it is called The Beaver Defeater. It will keep beavers from building dams in critical areas such as culverts to stop the damages of Beaver flooding. You can check out the device for yourself at http://www.thebeaverdefeater.com