Chipmunk ID – any ideas?

Matt Miller and I were on the north rim of the Grand Canyon last week and I took a few photos of what I assumed was a Uinta chipmunk near the camp site. I didn’t realise at the time that Colorado Chipmunks are also present in the park. As our main target was Abert’s Squirrel we didn’t pay a lot of attention to this critter.

Would anyone like to say whether this animal is the Uinta or Colorado flavour?



  • Scott Flamand

    The stripes seem to extend all the way down the back and they appear, in the picture, to be very black. Those 2 characteristics would lead me to think Colorado. Uinta’s do not show as much contrast and usually have browner stripes. Also the stripes don’t usually go all the way down the back. (I do think I have seen exceptions to that last idea) When they are found in the same area the Unitas are usually found at higher elevations. All that being said they can be very hard to tell apart.

  • jj2b


    I did a good bit of research on the area this summer, and I found nothing about Colorado Chipmunks being on the Kaibab Plateau. Were you up around Jacob Lake when you saw it?

    I’ll second Scott’s skepticism about how far the dorsal stripes extend as a field mark, but because the stripes can appear differently depending on the animal’s posture. I have a series of shots of one chipmunk in CA where in most it appears the dorsal stripes go all the way to the tail, but in one shot there is a good 1-2 inches of gray rump in between.

    I am almost positive chipmunks can erect the hairs on their tails and change the appearance of the tails, maybe they can scrunch up the skin on their rumps 🙂

    They are a tough group, but puzzling them out is what makes it fun, IMHO.


    • Scott Flamand

      I just read that the subspecies of Uinta Chipmunk found in the Kiabab has darker stripes than the one I am used to seeing in Utah… so those dark stripes that I thought made it look more like a Colorado may not be that helpful. I agree with John that chipmunks can be tough and fun!

  • Jon Hall

    Thanks very much everyone who commented on this. I talked to a couple of biologists from the region and it seems that:
    1. Uinta and Colorado Chipmunks occur on the north rim (this photo was taken in the campsite) and Uinta are the more common in the area.
    2. The distinct stripes and orangey (rather than brown) colouration suggests it is a Colorado Chipmunk
    3. But it is almost impossible to tell the two species apart with 100% certainty.

    So I think I will have to put it down as an “I am not sure”!

  • vladimir dinets

    I am pretty sure it’s a Colorado. Assuming the photos (especially the top one) show the actual coloration, such bright orangish flanks would be way out of normal Uinta range. Uintas basically look grayish-brown, not orangish.

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