District wildlife biologist Bob Massey gave some reasoning for the rarity of roadkill beaver, a question raised by Len Genis with this photo of one in the south suburbs on I-57. Downstate biologist Bob Bluett added an interesting observation.
Good to hear from you. Although uncommon, it does happen. It is not something we actually track. However, there are a couple of reasons I can think of for the rarity.
1. Beavers are a mostly nocturnal animal, putting their active time at a time when traffic is generally lighter.
2. Beavers can be fairly large animals, creating natural avoidance by those driving when they are able to avoid them. If hit, the muscular beaver may also survive the encounter at least long enough to slip back into the water. In addition to road-kill, we sometimes get reports of beaver simply showing up dead.
3. Beavers are most comfortable in and close to wetlands, and do not venture far from water, even when seeking food. They are able to travel quite nicely via the culverts, road ditches, farm creeks and rivers; and don't really need to take out across roadways that often.
4. Even a large beaver has a very short profile, in which pick-ups and larger trucks simply pass right over them. When frightened, they can hunker down even tighter if necessary. This goes against one of the armadillo's escape mechanisms of bucking or springing to avoid predators which puts them right in the grill of oncoming traffic.
5. Road-kill beaver may be scavenged by predators such as fox, coyotes or even dogs. They are even picked up by people ( including highway departments) for a variety of reasons (during trapping season, have mounted for personal use, etc.).
Hope this sheds a little light on the subject.
It does, and makes a lot more sense than anything I came up with.
And Bluett made this interesting observation:
Seldom see road-killed beavers. An exception to this is when rivers are above flood stage and beavers' search for dry ground to sit it out leads them to elevated roadbeds.