Xerospermophilus tereticaudus
Silhouette: Joseph Smit · PhyloPic
In 3 days ~30% in a week ~60%
The round-tailed ground squirrel (Xerospermophilus tereticaudus), known as "Ardillón cola redonda" in Spanish, live in the desert of the Southwestern United States and Northwestern Mexico. They are called "ground squirrels" because they burrow in loose soil, often under mesquite trees and creosote bushes.
Most round-tailed ground squirrels are very small. Weight at birth is approximately 3.9 grams (0.14 oz). Adults weigh around 125 grams (4.4 oz). All have a long round tail and long, hairy hind feet. They have no fur markings, instead having a uniform sandy color, which matches the soil they burrow in. The underside of their body is usually a lighter shade. Round tailed squirrels average 204 to 278 millimetres (8.0 to 10.9 in) in length including the tail which is from 60 to 112 millimetres (2.4 to 4.4 in) long.
The gestation period is 28 days. An average of 5.4 pups are born in each litter. They reach sexual maturity at 325 days. There is little information on the longevity of these animals but one wild born specimen lived to approximately 8.9 years in captivity. They are prey animals for coyotes, badgers, hawks and snakes. Round-tailed ground... Wikipedia →
Recording0:21
United States · 2025
© Daniel Donovan · iNaturalist · CC BY-NC 4.0
Recording0:12
United States · 2026
© nmoorhatch · iNaturalist · CC BY-NC 4.0
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Saguaro National Park | 🇺🇸 United States | |
| 2 | Joshua Tree National Park | 🇺🇸 United States |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Arizona-Sonora Desert Museum | 🇺🇸 United States | |
| 2 | Jardin zoologique de la ville de Lyon | 🇫🇷 France | |
| 3 | Grizzly & Wolf Discovery Center | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Round-tailed Ground Squirrel sighting in Mesa on a given day, based on 62 verified sightings from GBIF citizen-science data. It is the 6th most-seen of the 12 mammals we can rate there. Over three days the chance rises to about 30%, and over a week to about 60%, if each day is a fresh chance.
February, April–May and July
In those months about 20% of wildlife watchers report a Round-tailed Ground Squirrel in Mesa on a given day, against under 5% in August to November, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Round-tailed Ground Squirrel sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
3rd of 3
Of the 3 cities where we can rate Round-tailed Ground Squirrel sightings, Mesa ranks 3rd at about 10%. The best odds are in Phoenix (United States, about 30%) and Las Vegas (United States, about 10%).
Same family: Sciuridae
The closest relatives of the Round-tailed Ground Squirrel that you can see in Mesa (family Sciuridae, Squirrels) are Rock Squirrel (about 50%) and Harris' Antelope Squirrel (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Round-tailed Ground Squirrel is recorded against all the mammals logged in Mesa (62 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
