The U.S. Fish and Wildlife Service Wednesday announced a recovery plan for the endangered Southern California population of mountain yellow-legged frogs.
The finalized plan, developed in response to legal action by the Center for Biological Diversity, calls for a wide array of recovery actions and research efforts to deal with the multitude of threats to the survival of the amphibian.
“With so few of these frogs left, it’s a relief to finally have a plan in place to help them survive,” said Jenny Loda, a CBD biologist and attorney dedicated to protecting rare amphibians and reptiles. “Non-native predators and pollution are the major threats, so this plan is a big step toward saving these remarkable little creatures from extinction.”
Since the 1900s, mountain yellow-legged frogs have disappeared from nearly all of their former range in Southern California, according to the CBD. By the 1990s, fewer than 100 were thought to remain in a handful of isolated headwater streams.
Predation by introduced fish, primarily non-native rainbow trout, is one of the best-documented causes of the frogs’ decline. Another primary threat is habitat damage from recreation and other factors, Loda said.
The recovery plan prioritizes the continuation of captive-breeding efforts and augmentation of existing populations, as well as reestablishing populations in areas historically occupied by the frogs.
The plan emphasizes dealing with major threats to the frog, including predatory non-native trout and pollutants, such as chemicals used in wildfire management and illegal marijuana operations. It calls for range-wide surveys and monitoring, research on genetic diversity and chytrid fungus and addressing recreational impacts, including those from hiking, swimming and rock-climbing.
“It will be no small feat to recover these highly endangered frogs in the wild, with their numbers so low, but we need to try,” Loda said. “I’m hopeful that our federal and local government agencies will do the hard work of stopping these frogs from being lost forever.”
The mountain yellow-legged frog occupies rocky, shaded streams with cool waters originating from springs and snowmelt. A “distinct population segment” of mountain yellow-legged frogs in Southern California has been federally listed as endangered since 2002.
Once the most abundant amphibian in the Sierra Nevada and Transverse Ranges, mountain yellow-legged frogs in Southern California lived across a wide range of elevations and in a wide variety of wetland habitats. But the frogs are now limited to 10 precariously small populations in the San Gabriel, San Bernardino and San Jacinto mountains.