In 2020, a moment of hope and excitement came when an endangered frog was captured in its tadpole form from the fire-ravaged mountains above Los Angeles.
But California’s amphibians may once again be the target of attack, necessitating a new rescue mission.
The fires are raging in the San Gabriel and San Bernardino Mountains, two of three mountain ranges in Southern California where mountain frogs survive in a few isolated streams. As of Saturday, the fires had burned more than 90,000 acres, and there are concerns the flames are encroaching on the frogs’ critical habitat.
“These fires are a high priority because they’re burning in the only place this species is known to live,” said Hans Singh, a biologist for the California Department of Fish and Wildlife’s South Coast region. The San Jacinto Mountains in Riverside County are the only other place the species hops.
On Thursday, Singh met with the U.S. Forest Service, the U.S. Fish and Wildlife Service and the U.S. Geological Survey to work out what to do about the frogs in the San Gabriel Mountains. (The San Bernardino Mountains are overseen by a different agency.)
He said that once it was safe, officials would travel to the rocky hillside to investigate what had happened to the frog.
Depending on what they find, “we may need to rescue the frog,” Singh said.
That could mean putting them in a cooler and taking them to a zoo to be part of a conservation breeding program, or it could involve releasing them into other rivers where they can survive.
“Each population is small and highly susceptible to stochastic events, particularly wildfires,” the U.S. Fish and Wildlife Service said of the frogs released last month.
The Mountain Yellow-legged Frog is named for its lemon-colored belly and hind legs.
If swooping in to save them sounds dramatic, consider their plight: Once native to the high mountains of the southern Sierra Nevada and Transverse Ranges, the frogs have, by some estimates, disappeared from California, with fewer than 200 of the medium-sized frogs thought to remain in the wild in Southern California.
Fires and extended droughts due to climate change are among the causes of this alarming population decline. Development, river diversions and other factors have caused the frog to lose its habitat. Disease and predation by invasive trout species have also exacerbated the frog’s plight. Marijuana cultivation and recreational use have not helped the situation, experts say.
The biggest threat, Singh says, is the secondary effects of the fires: Raging wildfires turn the green tree canopy and undergrowth to gray ash. The next rains then wash the bare soil and debris into rivers, physically displacing frogs and other residents and making it harder for them to find food.
When a forest is on fire, “the frogs will jump into the water to hide,” Singh said. “You don’t really think about whether a burning log will roll down and hit them.”
The Bobcat Fire, the largest in Los Angeles County history, has burned more than 100,000 acres and affected at least five frog “emergency sites” in the San Gabriel Mountains, according to a status assessment.
Frogs are of particular concern, but they are not the only aquatic creatures that may be at risk.
There is also growing concern about the Western Pond Turtle, California’s only freshwater turtle, which is found in more areas than the frog but is experiencing significant population declines.
Rescues and releases of dolphins, turtles and other sensitive species occur regularly.
Last month, USGS and CDFW workers rescued juvenile frogs from an area of the San Gabriel Islands where the population had “drastically declined” in a short period of time, Singh said. Last year, they documented 140 adult frogs. This year, they found none, but did find and pull up several juvenile frogs.
A federal survey of the San Gabriel Islands noted that the islands “have long been considered a stronghold for the frog,” but a survey this year found only one adult. Areas that once contained the frog are now off-limits to the public.
Around the same time the baby frogs were rescued, a group of small pond turtles that had been there since the Bobcat Fire also returned.
Singh didn’t miss the irony of the situation.
“We never expected a fire to break out less than a month after the release,” he said. “Sometimes you can’t predict the future. It’s really disappointing.”
Releasing mountain yellow-legged frogs in new locations and enhancing existing habitat is helping, a recent status survey concluded.
However, since our last survey in 2019, the threat has not changed or abated significantly.
When it comes to climate change and wildfires, “the timing and options for mitigating these threats are limited or unclear,” the report said.
