In partnership with the California Department of Fish and Game, the San Francisco Recreation and Park Department is rehabilitating the Lily Pond in Golden Gate Park. Phase one of the rehabilitation includes the removal of the highly invasive African clawed frog. The African clawed frog is a species of concern due to its ability to rapidly degrade aquatic ecosystems. Because of the frog’s invasive nature they are illegal to own, transport or sell without a permit in many states, including California. Under the supervision of the California Department of Fish and Game, an integrated, least-toxic approach to frog removal has been developed, which involves hand capture of the frog and the use of carbon dioxide in solution. In addition, the removal requires fencing the pond, cutting the vegetation within and around the pond, as well as covering the pond with netting and tarps. Following the removal of the African clawed frog, the Lily Pond will be positioned for future beautification and renovation, once funds are made available. We anticipate the 1st phase of the rehabilitation to be completed in Spring 2013.
The infestation of African clawed frogs at Lily Pond in San Francisco’s Golden Gate Park has been known for several years. The estimate is that at this time less than ten adult frogs remain in the pond. The California Department of Fish and Game (CDFG) has been assisting the San Francisco Recreation and Park Department (RPD) in its efforts to implement an effective Eradication Plan, and subsequently restore the pond and its environs to a visually pleasing public use destination. The recent PETA Alert Notice contains erroneous information regarding the joint efforts.
The establishment of a population of this species outside of its natural habitat (the arid/semiarid regions of southern Africa) are of particularly concern because of it profound disruptive impacts to aquatic ecosystems. African clawed frogs are scavengers and will eat almost anything living, dying or dead and any type of organic waste. African clawed frogs are highly invasive producing many hundreds of eggs each reproductive cycle, which in San Francisco's Mediterranean climate can occur up to four times a year. Translocation of this species outside of its current location could easily and significantly impact critical habitats for a number of California's aquatic organisms, including species listed under the Federal Endangered Species Act, such as red-legged frog, coho and coastal Chinook salmon, steelhead trout, California and giant garter snake, etc. The expansion of established populations within California associated with translocation of frogs from this location is a very real threat.
The recent PETA Alert Notice contains erroneous information. CDFG and RPD have not proposed draining the pond to suffocate the African clawed frog population. Such an action would be counter-productive in that it would likely result in dispersal of adult frogs and have little or no impact on aestivating adults or the eggs which would remain viable for some time. Further, adult African clawed frogs, although a fully aquatic species, are air breathers.
Another apparent error in the PETA Alert pertains to the number of African clawed frogs at this location indicating that it is likely that the pond contained over a thousand frogs. However, this is no longer the case as most all of the frogs have been removed. The joint efforts are now directed at the eradication of any remaining eggs and tadpoles with as much care as possible to undertake the eradication program in a humane a way.
For more information about the eradication plan, please contact California Department of Fish and Game:
Eric J. Larson,
Environmental Program Manager
California Department of Fish and Game
7329 Silverado Trail
Napa, CA 94558
707-944-5528; FAX: 707-944-5563