Tiny Endangered Mouse Gets Third Wild Home at Camp Pendleton
San Diego – October 06, 2026 -- San Diego Zoo Wildlife Alliance has established a third reintroduced population of endangered Pacific pocket mice at North San Mateo, a training area within Marine Corps Base Camp Pendleton.
The milestone marks 20 years since the Alliance launched its Pacific Pocket Mouse Conservation Program in 2006. Since then, the organization has released more than 500 Pacific pocket mice into new and existing populations across the species' native range in Southern California.
The mouse weighs about as much as three pennies
The Pacific pocket mouse is the smallest and one of the most endangered mammals in North America, roughly the size of a human thumb. Once believed extinct, it was rediscovered in 1993 when a small remnant population turned up in Orange County, prompting an emergency listing under the federal Endangered Species Act. Only three original wild populations survive today.