The California Ground Squirrel (Otospermophilus beecheyi), which used to be called the Beechey Ground Squirrel, is a very common rodent throughout the western U.S. and Baja California.  These seed-eating characters live in the ground, as their name suggests, in a network of burrows which they excavate themselves as a colony group.  Some of these burrows are used communally, however, each individual squirrel has its own private entrance. 

These ground squirrels are often preyed upon by rattlesnakes, and here at the UC Hopland Research & Extension Center, it is the large, adult Pacific Western Rattlesnake that fills this role.  The California Ground Squirrel has evolved with the rattlesnakes and has developed interesting behaviors to counteract the predation ...such as chewing the shed skins of rattlesnakes and then licking the pups to disguise their scent, sand-kicking the snake to get it to rattle which allows the squirrel to assess the size and risk-level of the snake, and swishing of its (squirrel's) tail (which is super-heated) which conveys a confusing message to the snake's heat-sensing organs.  All of these facts have been discovered by a UC Davis interdisciplinary research team over the course of several decades.  Some squirrel populations also have levels of immunity to the snake's venom.

Here at UC-HREC, the ground squirrel burrows and their feces play an important role in the reproduction of the sand fly which transmits a species of malaria found in Western Fence Lizards.