Happy 50th, Endangered Species Act!

Amy Gotliffe, VP Conservation
March 8, 2023

Calls to protect our nation's wildlife began in the early 1900s in response to the near extinction of species like bison, whose numbers were once in the tens of millions. it was clear that, without protection, many of our nation's native plants and animals would become extinct. After decades of building unified support to save our national heritage, in 1973, our country took unprecedented action, and Congress passed the Endangered Species Act (ESA).

Bison family at Oakland Zoo.

The ESA aims to prevent extinction and recover species to the point where the law's protections are unnecessary. The 50th Anniversary invites all of us to celebrate how far we have come and inspire our citizenry to do even more.

Zoos and aquariums have become an essential part of the recovery program for many endangered species listed under the Endangered Species Act. AZA-accredited (Association of Zoos and Aquariums) frequently partners with other organizations, including government agencies, to protect endangered species and their environments. With the help of keepers, veterinarians, researchers, and educators working for and with zoos and aquariums, many recovery programs have the tools and resources they need to prevent extinction.


At Oakland Zoo, we have also committed to this national vision for wildlife.


Many of our key Conservation Focus Species are U.S. endangered or threatened species: The grizzly bear, gray wolf, condor, and American bison, represented by animals at Oakland Zoo. Other work happens behind the scenes:

Two of Oakland Zoo's four rescued grizzly bears playing in their expansive pool at California Trail. Photo: Steven Gotz.

The riparian brush rabbit is one of California's most endangered mammals, threatened by a deadly virus, Rabbit Hemorrhagic Disease Virus Serotype 2 (RHDV2), and found only in California's Central Valley in the San Joaquin River's ecosystem. In partnership with the U.S. Fish and Wildlife Service, and the California Department of Fish and Wildlife, Oakland Zoo helps vaccinate these rabbits from the fatal virus and deter possible extinction.


The native yellow-legged frog, which once hopped throughout California's upper elevations, has seen a precipitous population decline of more than 90 percent in the past decade due to chytrid disease. This skin fungus thickens the frog's skin so they can't breathe. Oakland Zoo collects tadpoles, inoculates them, then releases them back to the wild. 

A yellow-legged frog inoculated against chytrid and released back into the wild.


Without zoos, there would be no Condors. In 1986, the last wild California condor was taken into captivity, amounting to a mere 27 remaining California condors on our planet. Luckily, an alliance of organizations and zoos came together to conserve, breed, and release these giants into the wild, bringing to a halt the extinction of a magnificent species. Oakland Zoo is proud to be part of the California Condor Recovery Program to help rehabilitate sick and injured Condors.


Gray wolves in California are protected by Oakland Zoo's collaboration with the California Department of Fish and Wildlife and Working Circle to bring ranchers and conservationists together to steward a shared landscape.

Resident Oakland Zoo gray wolf male Sequoia, with pups, 2019. Photo: Steven Gotz.

Oakland Zoo collaborates with many partners doing critical work for black-crowned night herons, mountain lions, and black bears to keep them off the endangered species list, where we envision all American animals belong.


Oakland Zoo's Public Campaigns protect other endangered species from the threats of the illegal wildlife trade and deadly encounters in our oceans from single-use plastics. Our dynamic education programs inspire compassionate and activated Bay Area youth, ensuring a hopeful future.

Members of Oakland Zoo's Heron Rescue Team surveying downtown Oakland rookeries for black-crowned night herons in distress.


Remember the bison that inspired the origins of the Endangered Species Act? Oakland Zoo is part of an historic alliance that breeds heritage bloodline bison onsite and releases them into the wilds of Montana and the care of the Blackfeet Nation people, ensuring this species never comes close to extinction again.


Oakland Zoo is on the ground, in the field, across the country, and in partnership with our community, to support this incredible national vision. 


Happy birthday, ESA! Take it from the 100-year-old Oakland Zoo; the best is yet to come.