By Julian Schoen
The California red-legged frog, listed on the federal government’s endangered species list, is the subject of a habitat conservation project that aims to increase the frog’s population and solidify its survival.
Graniterock Company has redeveloped a quarry near Wilder State Ranch in Santa Cruz to create permanent man-made ponds that will harbor the fragile amphibians.
Dana Bland, a monitoring biologist working with the company, shared the blueprints of Graniterock’s restoration plan.
“They set aside an 11-acre plot where they mine sand,” Bland said. “They’ve put in one pond for the frogs.”
The need to preserve the frogs’ habitat has been sparked by threats from invasive foreign predators such as the bullfrog. Human destruction of natural terrain due to expansion and development has also led to the shortage of frog communities.
The California red-legged frog has recently seen a steep decline in its species count across the Central Valley.
However, Tim Hyland, assistant state park resource ecologist for the California Department of Parks and Recreation, explained that Santa Cruz was not specifically associated with the drop in red-legged frog populations.
“Santa Cruz today is still a stronghold for the red-legged frog,” Hyland said. “The listing by the U.S. Fish and Wildlife Service was not based on Santa Cruz, but the whole Central Valley. It was once a big wetland, and now has been drained for agricultural purposes.”
Valentine Hemingway, a UCSC graduate student in ecology and evolutionary biology and an intern at the Elkhorn Slough Natural Estuarine Research Reserve, elaborated on the substantial habitat loss of the frogs.
“Many amphibians worldwide are facing the consequences of habitat loss,” she said. “The threat is worldwide.”
Hemingway, satisfied with the conservation project, expressed some concern over the construction of permanent ponds that function year-round.
Having studied the species in depth, Hemingway said that the preferred habitat for the red-legged frog is ephemeral pools. These pools, which the frogs use as a breeding pond, only hold water for part of the year.
Although the frogs can still function in perennial pools, such pools also accommodate the California red-legged frogs’ predators, mainly the bullfrog, she said. “Permanent pools are good for toads, bullfrogs and fish that compete with the red-legged frogs,” Hemingway said.
Despite these fears, there is an air of optimism surrounding the project. Hyland added that the red-legged frogs are an integral part of the California environment and contribute to its wide diversity.
“The frogs have evolved here and are part of the landscape,” Hyland said. “They make California a special place. As long as we value the diversity of California, we must value the frogs as a component to it.”