This Brown Rat (Rattus norvegicus) checked out the infrared camera at a time when the Burrowing Owl, normally perched on the rock in the background, had flown away. That was wise timing. Arguably the owl is big enough to make this rodent’s life nasty, brutish, and short.
The rodent’s scientific name, Rattus norvegicus, by the way, is deeply unfair to Norway. As the Wikipedia article points out, at the time that British scientists stuck this label on the rodent, it was unknown in Norway.
In the 1960s and 70s, when this was the city dump, it swarmed with rats. Since the rats’ food source was covered over in the 1980s and the dump became a park, the assumption was that the rodents would go away. Apparently, some have stuck it out. Rats are said to be amazing burrowers, fully on a par with ground squirrels and gophers. Who knows? Maybe they’re feeding on Berkeley’s old garbage still.