Bringing back California’s native frogs
When Al Murphy first took the reins at the UC Hopland Research and Extension Center (HREC) back in the 1950s, he had the joy of listening to California red-legged frogs living in a couple of perennial ponds. Maybe it was the frog chorus or just the rarity of year-round water that made Al and his staff decide to keep the sheep out and declare the ponds a biological area. Despite the designation as a biological area, the ponds have lost a good deal of biodiversity since Al's time.
The native frogs took a beating thanks to bullfrogs and exotic fish such as large-mouth bass that were introduced for sport fishing and by the time Kevin Lunde did his Ph.D. on chorus frogs at HREC in 2011, there were no native frogs to be found in the ponds. Also, by removing grazing and the use of fire to manage the rangelands surrounding the ponds, tule reeds dominate the pond's edge and invasive plants such as vetch spread across the higher ground.
The recent periods of drought are devastating for most of California's ecosystems, but were good news for the ponds. They went completely dry for the first time in recorded history, and the largemouth bass died off. The long, dry period also puts us at an advantage for bullfrog eradication while the habitat for the species is limited. As part of the restoration efforts, HREC staff removed some of the bullrush and community volunteers along with members from the California Conservation Corps spent the day translocating spike rush plants from nearby locations to the recently cleared areas along the edge of the pond to provide additional warm, shallow sunning areas for native amphibians.
Only time will tell if the spike rush takes hold and, in the meantime, we hope volunteers will return to help get rid of some bullfrogs. If we can keep the bass out and the bullfrogs under control, we can look forward to a time when red-legged frogs can safely return to HREC.
Thanks, HREC staff and GrizzlyCorps member Mona Latil-Quinn, for your help.