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National Park Service
U.S. Department of the Interior
San Francisco Bay Area Network
Resource Briefing July 2010
Red Legged Frogs at Mori Point
The Importance: What are the long-term threats to the survival of the California
red-legged frog?
The federally threatened California red-legged
frog (Rana draytonii) has been eliminated
from 70 percent of its former range, which
once extended from Mendocino County to
Baja California. It is now found primarily in
coastal drainages in central California, from
Marin County south to San Simeon.
In the 1880s, a booming commercial
demand for frog’s legs led to over-harvest
of this species. Today, the primary threat to
red-legged frogs comes from habitat loss
caused by human activities and natural
disturbances like agriculture, timber harvest,
California red-legged frog (Rana draytonii)
development, and recreation. The degree of
threats varies by geographic location, and
many populations are threatened by more than one of these factors at a time. Additionally, numerous
non-native plants and predators have been introduced into existing habitat. In particular, predation
by introduced bullfrogs and fish has significantly contributed to the decline of red-legged frogs. These
non-native species were introduced to California in the late 1800s and early 1900s, and have become
established throughout most of the state.
Mori Point in the Golden Gate National Recreation Area is a prime example of a site where red-legged
frogs have been affected by human disturbance. Prior to the National Park Service’s acquisition of the
land in 2004, a history of intensive recreation had caused a large network of informal trails that eroded
the landscape and altered its hydrology. These activities had significant impacts on critical habitat for
the red-legged frog and many other species.
The Project: Golden Gate National
Recreation Area and Golden Gate National
Parks Conservancy have conducted an
extensive habitat restoration project on the
newly-acquired land at Mori Point.
The recovery plan for the California red-legged
frog, released in 2002, is a collaborative effort among
the U.S. Fish and Wildlife Service and several other
organizations. The plan details a number of actions
to guide management and recovery of the species.
Newly constructed trail at Mori Point
Newly constructed elevated boardwalk at Mori Point protects red-legged frog habitat (Photo: Mason Cummings)
Because of the geographically varied status of this species and differing levels of threats throughout its
range, recovery strategies differ by site.
Overall, the strategy for recovery of the
species involves four steps:
1. Protecting existing populations by reducing threats.
2. Restoring and creating habitat that will be protected and managed in perpetuity.
3. Surveying and monitoring populations and conducting research on the biology of and threats to the species.
4. Reestablishing populations within its historic range
A crew of volunteers helps plant native vegetation around one of
the newly restored frog ponds at Mori Point
The Mori Point restoration project was
conceived to address the need to protect
habitat for the various federally listed species at the site. In response to the problem of encroaching
trails and related patterns of erosion, the Golden Gate National Recreation Area and its partner
organizations worked to construct a well-defined trail to guide visitors away from disturbed areas,
restoration areas, and sensitive habitats. The project’s long-term benefits are drawn from improved
hydrologic connections between wetlands, uplands, and ponds. Frog pond restoration continues
today with the planting of thousands more native wetland plants.
Additional Resources:
Summary written by Mason Cummings. For more information regarding the Mori Point restoration
project, contact Susie Bennett, [email protected], or for more information about red-legged frogs
contact Garry Fellers, [email protected]