On September 19, 2005, the Center for Biological Diversity won a lawsuit against the Environmental Protection Agency (EPA) that requires the agency to consider the harmful effects of chemical pesticides on the California red-legged frog. The red-legged frog is listed as threatened under the federal Endangered Species Act (ESA).

In October 2006, the EPA and pesticide industry representatives signed a settlement agreement with the Center that prohibits use of 66 pesticides in and adjacent to core red-legged frog habitats throughout California until the EPA completes formal consultations with the Fish and Wildlife Service. The agreement requires the EPA to:

• complete formal consultations with the USFWS on the impacts of the 66 pesticides on red-legged frogs within 3 years;
• prohibit interim use of the 66 pesticides within and immediately adjacent to red-legged frog habitats, specifically designated critical habitat areas, aquatic features and upland habitats occupied by the frog;
• mandate pesticide-free buffer zones adjoining frog habitats (200 feet for aerial pesticide applications to prevent drift and 60 feet for ground applications to prevent runoff);
• allow exemptions for public health vector control programs, invasive species and noxious weed programs, uses approved under the Endangered Species Act, and other specific applications that pose little or no risk to frogs; and
• distribute an educational brochure for pesticide applicators and county agricultural commissions regarding the red-legged frog, impacts of pesticides and contaminants on frogs generally, and describing the interim restrictions on pesticide use in the settlement.

View the settlement agreement: final motion to enter stipulation, final stipulation. Read a press release about the settlement. View a map of the areas affected by the settlement.

The EPA's pesticide registration program is allowing thousands of pesticides to be used across California that may be harming the threatened California red-legged frog. Under the Endangered Species Act, the EPA is required to consult with U.S. Fish and Wildlife Service to determine if any of EPA's activities are harming listed species. A federal District Court ruling requires that the EPA must now initiate “consultation” under the Endangered Species Act for 66 of the most toxic and persistent pesticides authorized for use in California. View the CBD press release on the court ruling.

Recent studies (Declines of the California Red-legged Frog: Climate, UV-B, Habitat, and Pesticides Hypotheses. Pesticides and Amphibian Population Declines in California, USA.) have indicated that pesticides, particularly from large agricultural users, are negatively impacting populations of California red-legged frogs. The red-legged frog may not be the only species harmed by pesticides. Amphibians are declining across the globe and many scientists believe that industrial chemicals and pesticides may be to blame.


In a hard fought victory involving over thousands of supporting letters from the public and two federal lawsuits, the Center for Biological Diversity, the Jumping Frog Research Institute, Pacific Rivers Council, and the Center for Sierra Nevada Conservation won the designation of 4.1 million acres in 28 California counties as "critical habitat" for the endangered California red-legged frog. Building industry groups sued in 2001 to stop the habitat designation after critical habitat was originally designated on March 6, 2001. On April 13, 2004 the Fish and Wildlife Service re-designated 4.1 million acres of critical habitat in 31 separate areas. (Federal Register, Critical Habitat Proposed Rule). The Fish and Wildlife Service published a Recovery Plan for the California red-legged frog in May of 2002.

photo by Dr. Mark Jennings
photo by Dr. Mark Jennings

As defined by the Endangered Species Act, "critical habitat" includes all areas necessary to ensure the survival and recovery of threatened and endangered species. Federal agencies are not permitted to fund or authorize any activity that destroys or "adversely modifies" critical habitat areas. On federal lands managed by agencies such as the U.S. Forest Service, Bureau of Land Management, and the Bureau of Reclamation, such activities typically include timber sales, livestock grazing allotments, road construction, water diversions, and dams. On private lands, critical habitat is only protected if a federal permit or federal funding is required. Timber sales and large construction projects, for example, often require Clean Water Act permits and/or permits for the "take" of threatened or endangered species.

The Celebrated Jumping Frog of
Calaveras County

“Smiley said all a frog wanted was education, and he could do ‘most anything—and I believe him. Why, I’ve seen him set Dan’l Webster down here on this floor—Dan’l Webster was the name of the frog—and sing out, ‘Flies, Dan’l, flies!’ and quicker’n you could wink he’d spring straight up and snake a fly off’n the counter there, and flop down on the floor ag’in as solid as a gob of mud, and fall to scratching the side of his head with his hind foot as indifferent as if he hadn’t no idea he’d been doin’ any more’n any frog might do. You never see a frog so modest and straightfor’ard as he was, for all he was so gifted. And when it come to fair and square jumping on a dead level, he could get over more ground at one straddle than any animal of his breed you ever see.”

-Mark Twain

Mark Twain's Jumping Frog Nearly Extinct

The California red-legged frog is the largest frog west of the Continental Divide. Once so common it was a staple cuisine in San Francisco and Central valley, its numbers have plummeted to near extinction in recent decades. While Mark Twain's contemporaries instantly recognized the feisty hero of his tale The Celebrated Jumping Frog of Calaveras County as a California red-legged frog, few people today have been lucky enough to witness its famous leap.

It was once so abundant as to be a major human food source in the Bay area and the Central Valley. About 80,000 frogs were consumed annually in the late 1800s and early 1900s. As the population declined, bull frogs were exported from the East Coast to keep the "froggery" going. Bull frogs, however, are voracious predators. They helped drive the red-legged frog (and many other species) lower yet. Habitat loss to logging, wetland draining, water diversions, dams, cattle grazing, pesticides, urban sprawl, and agricultural expansion also decimated the species. California has lost 90% of it historic riparian areas and wetlands.

The California redlegged frog was listed under the Endangered Species Act in 1996. Historically common from Point Reyes National Seashore, inland to Redding and southward to northwestern Baja California, Mexico, it has been extirpated from 70% of its range. Its population has declined by at least 90%. It currently occupies coastal drainages in central California and scattered streams in the Sierra Nevada. A single population remains in Southern California. Rangewide, only four populations contain more than 350 adults.

The Global Amphibian Crisis

The red-legged frog is not alone in its plight. Amphibians are declining across the globe. While some scientists suspect a few central causes may be at work, others believe amphibians are being driven extinct by the same calamities threatening plants and animals in every ecosystem: habitat loss, water pollution, air pollution, ultraviolet light exposure, global warming, predation by introduced exotic species, and disease. While most species face only a few of these threats, however, amphibians seem to be susceptible to all of them. Though humans breathe through internal lungs which are protected from direct contact with air and water, for example, amphibians breathe partly (in some instances, completely) through their external skin. This places them in constant contact with the environment and all its pollution, radiation, and disease. Yet amphibians are not weak species. They have survived for millions of years- much longer than humans. Their decline may signal subtle yet radical ecosystem changes which could ultimately claim many other species including humans.

graphic Andrew Rodman ©2002
February 11, 2010
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