I saw a small white mammal dash under a log a few weeks ago, and reflexively thought I’d seen an ermine. It was about a half mile up in the woods behind the house. It took a minute to dawn on me that it was summer, and ermines should be brown now.
I went back the next day and staked things out, and learned the animal was, in fact, an albino chipmunk. I also learned I was no nature photographer. The best I’ve been able to do so far was a poor cell phone picture and some flashes of game camera video. But it has been a good learning experience.
I was able to locate the burrow the white chipmunk was seeking refuge in, which seemed a good indication I was in the core area of its home range. It appeared to be young-of-the-year, based on its size. According to Mark Elbroch and Kurt Rinehart, in their book “Behavior of North American Mammals,” chipmunks are born blind and hairless in April or May, after a month-long gestation. But in just five weeks they emerge from their natal den and are ¾ of their adult size.
I set up a game camera and recorded thousands of videos over a seven day stretch. With the exception of false triggers, a gray squirrel who occasionally sauntered by, and oddly, a hummingbird, all the other daytime pictures – hundreds of them – were of chipmunks. But the white one appeared in only about a dozen of the photos, spaced semi-regularly over the whole seven day span. It just didn’t come out very much.
So why? It could simply be that it’s a young animal and not yet brazen enough to venture far. According to Elbroch and Rinehart, young of the year stick around the natal den for one to three weeks after first emerging, building courage, learning through play. There were several videos of a different young-of-the-year chipmunk chasing the white one, which seems to jive with this.
After the exploratory window, the mother bars the kids from the den and they disperse. Chipmunks are solitary animals, and with the exception of breeding seasons and the child-rearing window for mothers, they spend their lives alone.
Of course another theory as to why the white chipmunk doesn’t come out much is that its eyes are bad. People with albinism are considered legally blind. So if it is a true albino, and all the footage I’ve seen suggests it is, it likely has vision problems.
So how rare are albino animals? According to the National Organization of Albinism and Hypopigmentation, one in every 18,000 – 20,000 people in the U.S. has some type of albinism. A web search turned up an abstract from 1954 that estimated rates of albinism in gray squirrels in Maine at 1 in 10,000 – that’s the closest I could get to chipmunk. The Missouri Department of Fisheries documented a ratio of 1 in 20,000 in their stocked catfish inventory. We’ll never find an actual number, but safe to say it’s pretty rare.