|Rana draytonii, WEI|
Sharp Park Golf Course contains two threatened species the California Red-legged Frog, Rana draytonii, a species that has lost much of its habitat to development and a species that is often referred to as “Twain’s frog” because it was the central character in Mark Twain’s short story “The Celebrated Jumping Frog of Calaveras County,” it was a favorite competitor in jumping frog competitions—until the California red-legged frog was displaced by species imported from other parts of the world. Rana draytonii became a staple of the diet of the forty-niners during the California Gold Rush, and eventually became an item on the menu of San Francisco’s finest dining establishments. The golf course operation has been killing California red-legged frogs for many years. Every year when normal winter rains occur frogs begin to breed at Laguna Salada and Horse Stable Pond, laying egg-masses that attach to aquatic vegetation. Because of the golf course’s poor design and unfortunate placement, these same winter rains cause several of the golf course’s fairways to flood. For many years, the golf course would simply pump the water through the sea wall and drain the water off the course: and in the process strand frog egg masses that would desiccate and die, losing entire generations of this threatened species.
|Thamnophis sirtalis tetrataenia. WEI|
Sharp Park has also provided excellent habitat for the San Francisco Garter Snake, Thamnophis sirtalis tetrataenia. The snakes used Laguna Salada, a lagoon for feeding and the surrounding upland refuge areas and basking habitats. In the 1940s, herpetologist Wade Fox surveyed Sharp Park for the first time, and found the species abundant, suggesting the population was present long-before the recently constructed golf course altered the species’ habitats.
However, Fox also discovered that the golf course was having detrimental impacts on this endemic snake. 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. The population crash and the 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 San Francisco garter snake was protected by federal law by 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. For more information on these two species and the park visit the Wild Equity web site.