Name those Rodents
Chip
October 19, 2023 - Late summer and fall are a very busy time here. Squirrels are frantically collecting and storing every edible thing they can find. If they happen to find another squirrel’s “pantry” a bit of stealing follows. One, which I will call Chip, zips behind a large rock with an acorn. Another, Giant Man, watches then zips in when Chip leaves. It would be funny but Chip is doing all the work and gets very little reward meaning he probably won’t make it through the winter. About four weeks ago a third squirrel entered the competition for food. I‘ll call the third squirrel Lotto.
All three are different species of squirrel. Chip is clearly a chipmunk. Giant Man is about seven times Chip’s size. Both are ground squirrels. Lotto is a tree squirrel. He’s about five times Chip’s size. Giant Man steals from everyone. I’m not familiar with any of their species. Sure I have seen tree squirrels and chipmunks but not these specific species.
Five species of chipmunk live in Colorado. They are Cliff, Colorado, Hopi, Least, and Uinta. Here is a summary of their basic traits.
Cliffs - Small size, lives in northwest Colorado
Colorado - Medium to large size, Southern Colorado to the Front Range, very distinct dorsal stripes
Hopi - Small size, from Yampa river south to Eagle county west to Gunnison, have very little black in dorsal stripes
Least - Smallest size, Dispersed communities throughout the state, five dark stripes with four light stripes
Uinta - Medium size, western Colorado and eastern Utah, more red/orange in color than other chips, back has three dark and four pale stripes, white dots on ears
From these location, Chip could be either a Hopi or Least Chipmunk but he has clear black stripes which eliminates Hopi. Also he is very small. A Least Chipmunk is typically 0.88 to 2.33 oz compared to an Eastern Chipmunk which is 2 to 5 oz. Knowing what he is, I was curious about his life expectancy which is 2 to 6 years.
Chip, a Least Chipmunk (Neotamias minimus)
For scale, the two buds on the twig behind him are 2.25 “ apart and the diameter of the twig in that area is 1/16”.
As for Giant Man, he also has stripes on his back but not on his face as seen below. The lack of stripes on his face means he is not a chipmunk. He clearly is not a marmot or a prairie dog which, for this part of the state, means he is a Golden-Mantled Ground Squirrel (Callospermophilus lateralis). They have two light colored stripes on their back which are surrounded by darker fur.
Giant Man Showing his Strips
This species is 9 to 11.5 inches long (tail included) and weighs between 4 and 14 oz.
Giant Man Eating Stolen Acorns
That leaves the tree squirrel, Lotto. I called him Lotto because he spends most of his time in our Gambel Oak. (Gambel for the oak tree and gamble meaning games of chance are spelt differently. Still, close enough to name a squirrel.) At first I though he was an Albert’s squirrel because he is dark gray to black with a white underside. But Albert’s prefer Ponderosa Pine and typically have ear tufts. They can lose the tufts from July to September. But I don’t see them growing back. Also Lotto is too small.
The other two options would be Red and Fox squirrels. Fox are the largest of the tree squirrels in Colorado and Red are the smallest at 0.4 to 0.56 lbs. From his eating habits and size I am concluding that Lotto is a Red squirrel whose winter color just happens to be on the darker side.
Lotto
I’m thinking that Lotto must have left his mom’s territory about a month ago to establish his own at our house. Work hard little guys. Winter is cold and long.