Looking for Round-tails

It's that time of year...















when round-tailed ground squirrels (Spermophilus tereticaudus) wake up from winter hibernation and venture out of their underground burrows searching for new plant growth to eat. Round-tails look similar to groundhogs and prairie dogs, but they're much smaller, only about a quarter pound.
An amusing groundhog-like behavior they have is to stand up on their hind legs watching for predators. And, they will peep or whistle to warn others of impending danger.
Sabino Canyon is home to three kinds of squirrels, all ground dwellers. The most common are round-tails, and also easy to find are Harris' antelope squirrels, which resemble chipmunks. I rarely see rock squirrels; they are the closest to "normal" looking tree squirrels, but their tails aren't as bushy. These round-tail photos were taken at Sabino Canyon last summer. I hope to take more pictures of ground squirrels at the canyon this year.

This round-tail was peaking out from under a trash receptacle where it was hiding.
Then, it came out to get a quick drink from a puddle of rainwater.
It looks like the squirrel uses its tail the way a kangaroo does to help balance when standing up.

I've always been fond of squirrels. Growing up in Southern California, tree squirrels held my attention before I became interested in watching birds. I was surprised to learn that there are not any native tree squirrels in the Sonoran Desert. It does make sense though, since there aren't many tall trees. And it is cooler underground for desert squirrels. We haven't seen any squirrels in our yard yet.

But, I recently noticed dirt mounding up under some shrubs and discovered this nearly 2" wide hole in the ground under the bushes, and a weed with some tender ends nibbled off.


According to my field guide to desert holes, openings of the burrows of round-tailed ground squirrels are from 1.5 to 2.5 inches. I found it interesting to learn that they dig a network of tunnels with nest chambers three feet deep. I don't know how any animal can dig through the hard layer of caliche in my yard, but we'll see what happens.

I also found this strange cat atop a nearby wall overlooking our garden. So, maybe I won't be seeing round-tails in our yard, but I'm still on the lookout for them at Sabino Canyon.
Update: I spotted my first round-tailed ground squirrel of 2009 at Sabino Canyon on February 27th. This one was peaking out of a hole that was heavily guarded by spiny cholla stems.
This post is included in Carnival of the Arid #2. Visit Chris Clarke's Coyote Crossing to see more posts about deserts from around the world.