Recovery Plan for the Northern Spotted Owl - DRAFT

each population of these animals is genetically unique and that when onepopulation is extirpated, a portion of the genetic diversity within the species inquestion is lost and probably is not recoverable. This information, coupledwith the concerns raised by Blaustein and Wake (1990) with respect to recentglobal declines in many amphibian populations, calls for careful considerationof the impacts of management practices on populations of these animals.Del Norte Salamander (Plethodon elongatus)Distribution and habitat.-The Del Norte salamander occurs in humid coastalforests from near Port Orford, Curry County and Powers, Coos County, Oregon,to near Orick, Humboldt County, California, and inland to near Salyer, TrinityCounty, and Seiad Valley, Siskiyou County, California, from sea level to around3,900 feet (1,200 meters) (Stebbins 1985). It is often found in rock rubble ofold riverbeds, road fills, outcrops, and moss-covered talus. It generally occursin drier situations than the Dunn's salamander. Stebbins (1985) andHerrington (1988) found that the Del Norte salamander occurred almostentirely in forested talus areas. Using time-constrained search methods,Raphael (1988) found the species present in all six of his forest seral stages butmost abundant in mature and old-growth timber. Abundance seemed correlatedwith a hardwood understory. Welsh and Lind (1988) found this speciesto have a higher abundance in older forest stands and a lower relative abundanceon drier stands. Welsh (1990) considered the Del Norte salamander(along with the Olympic salamander and the tailed frog) to be a species longassociated with elements of the arcto-tertiary forest.Ecology and management.-Welsh (1990) stated that the close association ofthe Del Norte salamander with old-growth forests probably is due to thepresence of microhabitat and microclimate factors that occur there, and thatthe species has evolved with habitats existing only in these forests. Thespecies retreats to deeper crevices in talus during hot, dry, or cold periods, butmay occur under surface objects during warm, wet weather (J. Beatty, OregonState University, Corvallis, pers. obser). The Del Norte salamander has a fairlylimited distribution in southwestern Oregon and northwestern California.Within its range, it most often occurs in moist (not wet) situations, usuallyassociated with talus or outcrops in older forests. Raphael (1988) has estimatedthat removal of old-growth fir forest within its range would result in a 75percent population reduction. Because of its restricted range and associationwith older forests, no timber harvest should be considered in conservationareas where this species occurs.Siskiyou Mountain Salamander (Plethodon stormi)Distribution and habitat.-The Siskiyou Mountain salamander occurs inJackson County, Oregon, and northern Siskiyou County, California. It is notsympatric with any other Plethodon, but occurs within 9 miles of P. elongatus(Brodie 1971). Populations of P. stormi are associated closely with talusdeposits and fissured rock outcrops. Individuals occasionally may be foundunder coarse woody debris, but only during the wettest weather and alwaysnear talus. Populations are densest on heavily wooded, north-facing slopeswith talus (Nussbaum et al. 1983).Ecology and management.-Soil temperatures where P. stormi have beencollected during daytime were 3.50 to 11.3 0 C. Individuals are closest to thesurface during spring (March to April) and fall (September to early November).However, even in dry summer weather, some may come to the surface to feedat night. They usually lie with their heads near the opening of their shelter392