Do beavers Despawn?

Multiple times now, Beavers have despawned before I have a chance to kill them all. Was wondering if this is just the way the game is coded or ?
Today, i found a small pack of beavers, 2 of them. I engaged the first one, took him down. Then, while im carving out his brain, and finish up, I look up and find the 2nd one has disappeared. I do a search of the area... nothing.
Its possible the beaver just took off and moved very far away. But I searched a good distance in all directions... nothing.
Was wondering, do they run if one gets attacked? Do they despawn?
The first several beavers Ive fought, i was able to kill the whole pack. The last 3 times Ive engaged them, they all disappear after I take down the first one...?
Today, i found a small pack of beavers, 2 of them. I engaged the first one, took him down. Then, while im carving out his brain, and finish up, I look up and find the 2nd one has disappeared. I do a search of the area... nothing.
Its possible the beaver just took off and moved very far away. But I searched a good distance in all directions... nothing.
Was wondering, do they run if one gets attacked? Do they despawn?
The first several beavers Ive fought, i was able to kill the whole pack. The last 3 times Ive engaged them, they all disappear after I take down the first one...?