FERC Project No. 2079 - PCWA Middle Fork American River Project ...

4.2 KNOWN CRLF RECORDS
4.2.1 Records Within the Study Area
There is only one known CRLF record within the study area (Table 2 and Map 3). In
June 2001, a single adult CRLF was observed in an ephemeral pool north of
Pennsylvania Point, on the western end of Ralston Ridge (CNDDB 2007, PG&E 2004).
Experts believe the frog was at this site during dispersal (Barry, pers. comm., 2007a).
The site, which is on a right-of-way below a PG&E transmission line, was almost
completely burned in the Ralston Ridge wildfire of 2006 and remains almost completely
denuded. The pond, which appears to have been formed in a depression caused by
ground disturbance and erosion resulting from logging operations, was completely dry in
2007 during helicopter surveys completed for this Site Assessment. No frogs have
been detected at the site since 2001 (Barry, pers. comm., 2007a).
No CRLF were observed during ground surveys conducted in 2007 for this Site
Assessment. In addition, there were no incidental sightings of CRLF recorded during
numerous aquatic surveys conducted for the MFP in 2005 through 2007 as part of early
relicensing studies.
4.2.2 Records Outside the Study Area, but within the MFAR Watershed
There are two additional CRLF records outside the study area, but within the MFAR
watershed (Table 2 and Map 3):
One CRLF museum specimen was found in the vicinity of Michigan Bluff, in
1916, approximately 1 1/3 mile north of the study area.
In 2006, a population of more than fifty CRLF was observed in ponds on private
land at Michigan Bluff, just less than one mile north of the study area. All life
stages were observed at the site (i.e., eggs, tadpoles, metamorphs, and adults),
and the population is believed to be reproductive (Fesnock, pers. comm., 2007).
4.3 CRLF HABITAT CHARACTERISTICS
4.3.1 Upland Habitat
The USFWS defines upland habitats broadly as those which “provide food and shelter
sites for CRLF and assist in maintaining the integrity of aquatic sites by protecting them
from disturbance and supporting the normal functions of the aquatic habitat” (USFWS
2006). For example, upland habitats may be riparian areas immediately adjacent to
aquatic breeding areas, or grasslands that contain seeps and springs (USFWS 2002).
Adult CRLF may move from spawning pools into deeply shaded forest streams during
the summer, and seek shelter in root masses and undercuts (Barry, pers. comm.,
2007c). Due to the fact that CRLF in coastal California are known to make longdistance
movements “without regard to topography, vegetation type, or riparian
corridors” (USFWS 2002), any upland habitat that does not contain significant barriers
to dispersal may potentially be used by CRLF. Barriers to dispersal defined by USFWS
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