Most days I take the dog for a walk in a wooded area near my house. Many of those days I see rabbits. Very often I see what appear to be the same rabbits in the same spots - similar size, similar position, exact same location. As the fall has progressed, I’ve noticed these rabbits have gone from brown to white. This seemed appropriate at the time, as they turned white just prior to the first snowfall.
However, we’ve had very little snow since then, mostly rain and above-freezing temperatures, and on more recent walks some of these recurrent rabbits seem to be showing a subtle increase in the overall number of brown hairs, almost as though they are backing away from a full-white coat and hedging their bets with a scattering of brown.
How quickly can rabbits change colour with seasonal changes? Can they go back-and-forth between colours within a season? Do they have to turn over their whole coat to make this work? - I realize that another idea would be that I’m seeing different rabbits, maybe the survivors after all the white ones get eaten, but that isn’t my impression.
Imp of the Perverse is my lovely and talented wife, sometimes mentioned on the boards as “Ms. Attack”. This is her first post here, so I thought I’d introduce her, and also ask for help with this vexing rabbit question. Yesterday I actually saw one of the rabbits in question, and they do seem to be semi-brown. Unlike Imp, I can’t say that I’ve seen this particular rabbit as a white rabbit before.
What do rabbits do if the snow never comes? Are they just screwed, wandering the verdant landscape with a big “eat me, I’m delicious” sign?
I can answer your last question. If snow never comes they’re just screwed. Their defense against predators is to lie very still, which doesn’t help as much when you’re a different colour than the landscape. If there’s at least a little snow here and there you might get away with it, but if no snow comes you get eaten and your species is out-competeded by rabbits that don’t turn white in winter.
Rabbits molt twice in a year, once in the autumn, when it turns white, and then in the spring, when its new fur grows in brown. It’s a biological adaption that they have no control over. If you removed this type of rabbit from it’s environment for example, it would continue to follow this color changing process.
Argh. I just read about one of the polar species and have forgotten again whether it was the polar fox or hare, but still: in this animal, the change from brown summer to white winter coat was triggered by temperature - so if the winter would get so mild that no snow came, they would presumably keep their brown coat. (and obviously, that’s why this trigger evolved over other ones, to counter mild winters with little snow).
The change in spring from white to brown was triggered by daylight lenght on the other hand.
Are you sure about that? Because I once read (or I believe I read) that for ptarmigan, it’s the length of the day that triggers the change from brown to white as well.
We don’t have rabbits up here, but I’ve seen hares (jackrabbits) crouching down under a bush, apparently totally convinced that their white pelt gives them ample camouflage among the brown and yellow grass. Even if they are a bit more prone to running instead of hiding when you get too close (like just outside the range of a normal shotgun)