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Below is some detailed information about the Salamanders being monitored
Western Redback Salamander (Plethodon vehiculum)
This species is found from southern Oregon to southern British Columbia,
west of the Cascade and Coast mountains (Stebbins 1985; Leonard et al.
1993). In British Columbia, they are found throughout Vancouver Island
and on the mainland in the Fraser Valley as far as Hope (Green and Campbell
1984). Curiously, they have not been recorded from any of the Gulf Islands
and are absent from most of the other islands surrounding Vancouver
Island. This contrasts dramatically with A. ferreus (see section 2.1).
Plethodon vehiculum are found within leaf litter and Sword Fern (Polystichum
munitum) bases, under moss, rocks or CWD on the forest floor, and under
or among rocks on talus and rock outcrops (Leonard et al. 1993). They
favour damp, but not wet, shady areas of the forest and can be very
abundant (Davis 1996, 1998). Ovaska (1988b) reported a high degree of
site-specificity and small home ranges. Most movements of individuals
between captures over a two-year period were < 3 m. On Vancouver
Island, salamanders move from underground retreats during warm wet weather,
so peak surface abundance occurs in the spring and autumn, depending
on recent weather conditions (Ovaska and Gregory 1989). Courtship and
mating occur mainly in October and November (Ovaska and Gregory 1989),
but eggs are laid the following summer. Eggs and nests are not well
documented, probably because eggs are laid beneath the surface (Leonard
et al. 1993). Hatchlings appear in the autumn and take two to three
years to reach sexual maturity (Ovaska and Gregory 1989). Prey consists
of terrestrial invertebrates.
There is no evidence that P. vehiculum are endangered at the present
time or that they require special protection. However, numbers are reduced
in clearcuts (Dupuis et al. 1995; Dupuis 1997; Davis 1996, 1997, 1998)
and in second-growth stands (Dupuis et al. 1995; Dupuis 1997). Abundance
varies greatly across apparently homogeneous habitat, but at least some
populations appear to be very stable (Davis 1996, 1998). Very dense
local populations may act as source populations for adjacent less favourable
habitat.
For natural history notes see Peacock and Nussbaum (1973), Ovaska (1987,
1988a,b), Ovaska and Gregory (1989), and Davis (1996, 1998). For field
identification, descriptions can be found in Nussbaum et al. (1983),
Green and Campbell (1984), Stebbins (1985), Leonard et al. (1993), and
Corkran and Thoms (1996).
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