Red-Legged Frogs and MALT-Protected Farmland

March 3, 2019

Protecting at-risk farmland from development does more than protect agriculture, it preserves habitat for wildlife.

And as stewardship project managers Kristin Guy and Eric Rubenstahl recently learned, one of the species benefiting from protected agricultural land is the California red-legged frog, a state and federally threatened species.

“A single MALT-protected property,” says Kristin, “can preserve hundreds of acres of habitat potentially used by spotted owls, red-legged frogs, coho salmon, bobcats, coyotes and songbirds, alongside cows, sheep, fruit trees and rows of vegetables.”

OUR STATE AMPHIBIAN: THE CALIFORNIA RED-LEGGED FROG

The California red-legged frog (Rana draytonii) is the official amphibian of the Golden State. Listed as threatened by California and federal agencies, this 2-5 inch creature, which can fit in the palm of your hand, makes its home from Northern California to the upper reaches of Baja California.

Currently, red-legged frogs inhabit 256 streams or drainages in 28 counties of California, primarily in coastal areas. In addition to loss and destruction of habitat largely in Southern California and inland, red-legged frogs contend with predation by non-native American bullfrogs (Lithobates catesbeianus) which were introduced from the Southern and Eastern United States.

Red-legged frogs need three distinct habitat types to thrive:

• Deep water habitat that allows them to escape from predators such as raccoons.
• Shallow water with cattails, rushes and other wetland vegetation that provides habitat for laying egg masses.
• Upland habitat which provides cover for foraging.

Importantly, managed grazed lands help red-legged frogs survive. The low grasses and bushes allow the frogs to more easily get around and see and avoid predators.

THE NIGHT SURVEY ON THE RANCH

Recently, Kristin and Eric joined Trish Tatarian, a biologist from Santa Rosa-based Wildlife Research Associates, to conduct a red-legged frog survey on a MALT-protected ranch in Hicks Valley. The goal of the survey was to simply determine the presence of red-legged frogs on a specific part of the property. This survey is a once-every-three-year event, measuring any change in the presence of this important and threatened species.

Kristin and Eric met Trish at the ranch as night fell and geared up with headlamps, flash lights and binoculars. Since this time of year is breeding season, the team focused on looking for the frogs near bodies of waters such as stock ponds, creeks and pools.

The team visited three different sites:

1) A larger pond with minimal wetland vegetation,

2) A smaller pond with abundant cattails and

3) An intermittent creek corridor littered with pools.

Why count frogs at night, you ask?

“We’re looking for eye shine,” said Eric. “By zooming in with binoculars we look for the distinguishing features to make sure that we are identifying red-legged frogs rather than American bullfrogs or other amphibians.”

“We have to watch our distance,” added Kristin. “If we get too close, we will spook the frogs, and they leap back into the deeper water for safety.”

The survey successfully confirmed the presence of red-legged frogs at this ranch, which in turn tells us that this habitat is continuing to support this species. In addition to finding reg-legged frogs, the team also found Pacific tree frogs (Pseudacris regilla), a California native species known for their vocal night chorus, and a common food source for the red-legged frogs.

THE CONNECTION BETWEEN MALT-PROTECTED LANDS AND WILDLIFE

From the rugged coastline and still waters of Tomales Bay, up deep redwood-shaded canyons, through chaparral, scrub and oak savanna, clear to the grassy tops of rolling ridges, Marin County provides refuge and resources for an extraordinary array of plants and animals.

Here you can find 41 animals and over 100 plants under special protected status, reflecting both the outstanding diversity and perilous fragility of our landscape.

When MALT protects a property, we make a promise to help permanently protect the land’s agricultural and natural values alike.

Our stewardship team works closely with landowners to advance sustainable land management. MALT offers landowners technical support, resources and funding for projects that protect or restore sensitive habitats like streams and wetlands, areas that animals like red-legged frogs make their homes.