The California Red-Legged Frog, Hopping for
Recovery of Its Species
Recovery of Its Species
by Phoebe Conrad
"The decline of California Red-Legged Frog signals a lack of diversity and environmental quality in wetlands and streams that are essential to clean water and the survival of most fish and wildlife species" --Ramekon O'Arwisters; Curator of Exhibition, SFO Museum, San Francisco International Airport
(savethefrogs.com)
savethefrogs.com
"The decline of California Red-Legged Frog signals a lack of diversity and environmental quality in wetlands and streams that are essential to clean water and the survival of most fish and wildlife species" --Ramekon O'Arwisters; Curator of Exhibition, SFO Museum, San Francisco International Airport
(savethefrogs.com)
Description and Ecology:
Endemic to California and Baja California, Mexico, the California red-legged frog is the largest native frog in the western US (savethefrogs.com). As for appearance, the frog is usually a brownish, olive, or reddish brown color, and its abdomen or hind legs are many times red (relating to the species' name), and its back has small black flecks with irregular dark blotches. Besides this reddish tint that they may or may not have, one of its most distinguishing features is a dorsal fold that runs from its eye, down its back, to its rear (Recovery Plan). Their breeding season is from November through about April, and their average life span is usually lower than eight years but can be up to ten. When it comes to their habitat, they are primarily found in pools, ponds, or bodies of quiet, standing water and places with plant cover, in a Mediterranean climate (californiaherps.com); they use a variety of parts of these habitats, however, including the aquatic, riparian, and upland elements. Some frogs complete a whole life cycle in one particular habitat, but others use various different habitats throughout their lifetime. When water levels may be receding, these frogs tend to seek refuge in other places like under boulders, organic debris, and agricultural features (Recovery Plan).
www.werc.usgs.gov
Geographic and Population Changes:
At some point, this frog could be found in forty-six counties, ranging from Point Reyes National Seashore, to Redding, to Baja California, but by now, it’s been extirpated from at least twenty-four of those locations. Because of changes in its geographic range, this recovery plan addresses the status of the California red-legged frog in each of eight recovery units, including the Sierra Nevada Foothills and Central Valley, the North Coast Range Foothills and Western Sacramento River Valley, the North Coast and North San Francisco Bay, the South and East San Francisco Bay, the Central Coast, the Diablo Range and Salinas Valley, the Northern Transverse Ranges and Tehachapi Mountains, and the Southern Transverse and Peninsular Ranges. In each of these diverse locations, the numbers of frogs has dropped dramatically since earlier in the 1900s (Recovery Plan).
Listing Date and Type of Listing:
This species was listed under the US Endangered Species Act as threatened on May 23rd of 1996. It’s Recovery Plan was established September 12th of 2002 by the lead agency of the United States Fish and Wildlife Service (californiaherps.com).
Cause of Listing and Main Threats to Its Continued Existence:
The California red-legged frog is threatened mainly by human impacts on its habitat, like "urban encroachment, construction of reservoirs and water diversions, contaminants, agriculture, and livestock grazing,” and exotic predators and competitors intruding habitats (Recovery Plan). These threats often contribute to habitat degradation and loss for the species, which leads to increased fragmentation of livable habitats, affecting the frogs’ abilities to disperse and move between different habitat patches as necessary. The main predators of the frogs are bull frogs, introduced fish species, raccoons, herons, snakes, and newts. Unfortunately, like many other amphibians, these frogs are heavily affected by the Chytrid fungus as well, which has wreaked havoc on frog populations all over the world (Recovery Plan).
Description of Recovery Plan:
Recovery status and strategies differ for each of the eight units established for the California red-legged frog. Depending on the status of populations in each unit, the recovery goals could be to protect existing populations or to increase and stabilize populations. However, the overall strategies implemented in the Recovery Plan consist of reducing threats to protect existing populations, restoring and creating habitat to be protected from here on out, surveying and researching the populations, the species' biology, and its threats, and reestablishing populations within the geographic range it has been known to occupy (Recovery Plan).
Delisting (which could occur by 2025, with more than $10, 031, 500 in costs) this species will only be considered if:
1. Core areas contain suitable habitats that are protected and managed and these areas
lack threats to their quality.
2. Populations have been stabilized throughout the species' range, determined by
successful reproduction and survival into later years of life, which will be monitored through
a population monitoring program for about 15-year periods.
3. These populations are evenly distributed throughout a geographic range that will
conduce continued existence of metapopulations.
4. The species is reestablished in parts of its historic geographic range that allows at least
one population to be stable or increasing in each core area where the frogs had been absent
in previously.
5. The amount of habitat needed for connectivity, recolonization and dispersal has
been determined and managed for the frog, which will offer opportunities of dispersal to
help genetic exchange and recolonization.
If interested in more information about the California red-legged frog species or how to save these frogs, check out these sites:
Endemic to California and Baja California, Mexico, the California red-legged frog is the largest native frog in the western US (savethefrogs.com). As for appearance, the frog is usually a brownish, olive, or reddish brown color, and its abdomen or hind legs are many times red (relating to the species' name), and its back has small black flecks with irregular dark blotches. Besides this reddish tint that they may or may not have, one of its most distinguishing features is a dorsal fold that runs from its eye, down its back, to its rear (Recovery Plan). Their breeding season is from November through about April, and their average life span is usually lower than eight years but can be up to ten. When it comes to their habitat, they are primarily found in pools, ponds, or bodies of quiet, standing water and places with plant cover, in a Mediterranean climate (californiaherps.com); they use a variety of parts of these habitats, however, including the aquatic, riparian, and upland elements. Some frogs complete a whole life cycle in one particular habitat, but others use various different habitats throughout their lifetime. When water levels may be receding, these frogs tend to seek refuge in other places like under boulders, organic debris, and agricultural features (Recovery Plan).
Geographic and Population Changes:
At some point, this frog could be found in forty-six counties, ranging from Point Reyes National Seashore, to Redding, to Baja California, but by now, it’s been extirpated from at least twenty-four of those locations. Because of changes in its geographic range, this recovery plan addresses the status of the California red-legged frog in each of eight recovery units, including the Sierra Nevada Foothills and Central Valley, the North Coast Range Foothills and Western Sacramento River Valley, the North Coast and North San Francisco Bay, the South and East San Francisco Bay, the Central Coast, the Diablo Range and Salinas Valley, the Northern Transverse Ranges and Tehachapi Mountains, and the Southern Transverse and Peninsular Ranges. In each of these diverse locations, the numbers of frogs has dropped dramatically since earlier in the 1900s (Recovery Plan).
californiaherps.com
Listing Date and Type of Listing:
This species was listed under the US Endangered Species Act as threatened on May 23rd of 1996. It’s Recovery Plan was established September 12th of 2002 by the lead agency of the United States Fish and Wildlife Service (californiaherps.com).
californiaherps.com
Cause of Listing and Main Threats to Its Continued Existence:
The California red-legged frog is threatened mainly by human impacts on its habitat, like "urban encroachment, construction of reservoirs and water diversions, contaminants, agriculture, and livestock grazing,” and exotic predators and competitors intruding habitats (Recovery Plan). These threats often contribute to habitat degradation and loss for the species, which leads to increased fragmentation of livable habitats, affecting the frogs’ abilities to disperse and move between different habitat patches as necessary. The main predators of the frogs are bull frogs, introduced fish species, raccoons, herons, snakes, and newts. Unfortunately, like many other amphibians, these frogs are heavily affected by the Chytrid fungus as well, which has wreaked havoc on frog populations all over the world (Recovery Plan).
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| scopeblog.stanford.edu |
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| soundwaves.usgs.gov |
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| frogmatters.wordpress.com |
Description of Recovery Plan:
Recovery status and strategies differ for each of the eight units established for the California red-legged frog. Depending on the status of populations in each unit, the recovery goals could be to protect existing populations or to increase and stabilize populations. However, the overall strategies implemented in the Recovery Plan consist of reducing threats to protect existing populations, restoring and creating habitat to be protected from here on out, surveying and researching the populations, the species' biology, and its threats, and reestablishing populations within the geographic range it has been known to occupy (Recovery Plan).
Delisting (which could occur by 2025, with more than $10, 031, 500 in costs) this species will only be considered if:
1. Core areas contain suitable habitats that are protected and managed and these areas
lack threats to their quality.
2. Populations have been stabilized throughout the species' range, determined by
successful reproduction and survival into later years of life, which will be monitored through
a population monitoring program for about 15-year periods.
3. These populations are evenly distributed throughout a geographic range that will
conduce continued existence of metapopulations.
4. The species is reestablished in parts of its historic geographic range that allows at least
one population to be stable or increasing in each core area where the frogs had been absent
in previously.
5. The amount of habitat needed for connectivity, recolonization and dispersal has
been determined and managed for the frog, which will offer opportunities of dispersal to
help genetic exchange and recolonization.
So after all of this information that I hope you found helpful, I leave you with this:
Let's save the frogs!
red-legged.causevox.com
If interested in more information about the California red-legged frog species or how to save these frogs, check out these sites:
http://www.biologicaldiversity.org/species/amphibians/California_red-legged_frog/
http://www.parksconservancy.org/conservation/plants-animals/endangered-species/red-legged-frog.html
http://wildequity.org/species/22
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