San Francisco garter snake
Thamnophis sirtalis tetrataenia

The San Francisco garter snake has been called North America’s most beautiful serpent. It is a fantastically colored species, reflecting the character of the City it is named for. It is identified by its reddish-orange head with red, black, and blue racing stripes on its sides and back.

Click here to learn how to identify a San Francisco garter snake.

Unfortunately this harmless and gorgeous critter isn’t easily seen, in part because it is on the brink of extinction. Restricted primarily to San Mateo County, the species’ preferred habitats—wetlands and marshes with access to upland basking areas—have been hit hard by agricultural, residential, commercial, and even recreational development. There may be only one to two thousand individual San Francisco garter snakes remaining in the wild today.

Historically Sharp Park provided excellent habitat for the San Francisco garter snake. It contained a vibrant feeding lagoon, now called Laguna Salada, and upland refuge areas and basking habitats where the snake could rest and warm itself in the sun. In the 1940s, Dr. Wade Fox surveyed Sharp Park for the first time, and found the species to be abundant and of remarkable purity, indicating that the population was present long-before the recently constructed golf course altered the species’ habitats.

But Dr. Fox also discovered that the golf course was having detrimental impacts on this beautiful serpent. He found a snake killed by golfers in 1946, and noted that the species probably was frequently killed in this manner. Over the next few decades the snake’s population crashed, and in 2006 the U.S. Fish and Wildlife Service concluded a dead snake found on the property was killed by the course’s lawn mowers.

According to the U.S. Fish and Wildlife Service, this San Francisco garter snake
was killed by a lawnmower at Sharp Park Golf Course.

The population crash and on-going take of the species is particularly worrisome because the survival of the Sharp Park population is key to the success of the species’ overall recovery plan. When the plan was written, Sharp Park had one of only six known potentially viable populations of the species. The plan states that at least four more would need to be established if the species is to have any chance of recovering. Unfortunately, the population at Sharp Park Golf Course has crashed since that time: there may be fewer than 10-20 individuals left on the property.

The golf course does not have a permit to harm the snake, so it does not have any authorized mitigation measures in place to ensure that the most beautiful serpent in North America is kept safe from the ongoing maintenance and operations of the course. With such a rare species, the killing of even a single individual represents a major blow to the population: which is why it is essential for San Francisco to stop the killing and implement recovery efforts for the species as soon as possible.

The San Francisco garter snake was protected by federal law as early as 1967, and was listed as an endangered species under the Federal Endangered Species Act when the Act was passed in 1973. It is also protected as a Fully Protected Species under California law, and therefore killing the species is not only illegal, but it is also impossible to get a permit to kill the San Francisco garter snake except for restoration projects and scientific research.

Since the garter snake was protected great effort has gone into conserving the species, including the creation of a recovery plan and controlling developments to ensure that the species’ habitats aren’t adversely modified. However, many obstacles still remain to the snake’s survival. Indeed, it is even starting to lose its favored prey: the California red-legged frog is itself threatened with extinction due to development and other threats. Restoring Sharp Park will help both imperiled species thrive.