Southern Pacific Rattlesnake
Crotalus oreganus helleri
Federal and State Protections
Countries of Occurrence
United States of America, Mexico
States or Providence
California (USA), Baja California (Mex)
The Southern Pacific rattlesnake generally grows to 30 to 44 inches in length and is highly venomous. The photo here is of a juvenile, and a range map of the other subspecies under C. oreganus is also below. Like most other rattlesnakes, they are generalist feeders and occupy a wide range of habitats. They also inhabit Catalina Island where they can be much darker than on the mainland.
Fun Fact: The venom of the Southern Pacific rattlesnake varies substantially between populations likely depending on habitat. In certain areas, this subspecies of C. oreganus has developed neurotoxic venom. You can also see in the map that this rattlesnake can only be found in California and Baja California.