What is the leading cause of death among beavers?

Answer 1

Surprisingly the leading cause of death among beavers is getting hit by a tree they just cut down. (Well actually if you think about it or have ever cut trees for firewood its not that surprising).

The next is starvation and or predation caused by the parents driving the young out of their territories in the fall. Beavers are actually quite territorial and are very vulnerable until they get a den.

The third is probably trapping.

Answer 2

I don't know of a reference, but in most places in the US, the leading cause of death is probably from trapping--beavers are intentionally removed because their dams can cause the failure of bridges, culverts, and drainage ditches.

Answer 3

In North Carolina, I would say being hit by cars. I have also read that over all, beavers are killed by falling trees, because they aren't very good at anticipating where the tree will fall.