📍 San Mateo
Eastern Fox Squirrel (Sciurus niger)
The all-black coat comes from a recessive melanistic variant that switches off the usual rusty-orange pigment, leaving individuals uniformly dark from nose to tail.
Fox squirrels are not native to California — they spread across the Bay Area after introductions in the early 20th century and now outnumber the native Western Gray Squirrel across much of San Mateo’s parks and neighborhoods.