DOI: 10.5063/aa/nrs.681.2
title: Pine Marten Habitat Preferences at Sagehen, California

description: MASTERS THESIS: Marten (Martes americana) habitat preferences were assessed in the Sagehen Creek Watershed, Tahoe National Forest, California, from July 1979 to September 1980. Fourteen martens were captured 47 times. The incidence of marten tracks on smoked aluminum plates in 42 baited plywood cubbies indicated that martens prefer red fir and riparian habitat associations: brush and Jeffrey pine associations were selected against. Radio-locations for 1 male and 3 female martens indicated preference for riparian associations in the lower Sagehen Basin, and for red fir associations in the upper Sagehen Basin (above 2050 m elevation). Mean home range size for the 4 martens was 3.74km^2. Inner isopleths of the harmonic mean home range model indicated intensive use of riparian areas and adjacent old-growth red fir stands. Micro-habitat analyses indicated that martens in the lower basin strongly prefered sites close to water or meadows having dense herbaceous cover and 40-60% tree canopy closure; in the upper basin martens preferred red fir stands, close to meadows, having high densities of large trees, snags, stumps, and logs. In the lower basin, martens foraged primarily in riparian habitats and near meadow edges, but often moved upslope into mixed conifers to find suitable resting sites; old-growth red fir stands were used both for foraging and for resting in the upper basin. Although live trees were frequently used as resting sites during summer, snags were strongly prefered. Snags used for resting were typically large, broken-topped fir snags retaining most of their bark. Live trees used for resting were usually large, deformed lodgepole pines having mistletoe (Aroeuthobium campylopodon) bundles. During winter, resting sites were beneath snow provided snow cover was sufficient; short, highly decayed fir snags or tall fir stumps were preferred, and 76% of all winter rest observations were in cavities containing chickaree (Tamiasciurus douglasii) middens. Forest management recommendations are proposed for 3 management zones: Zone 1 comprises riparian associations and meadow edges, Zone 2 comprises adjacent forest stands, and Zone 3 comprises more distant forest stands. Management objectives for Zone 1 emphasize maintenance of herbaceous ground cover. In Zone 2, timber harvest should be by single-tree selection (maintaining 40-50% canopy closure) or small group selection (&lt;0.25 ha). At least 8 snags/ha greater-than or equal to 38 cm dbh, including 1 greater-than or equal to 70cm dbh, should be retained, along with 6 logs/ha and 6 stumps/ha greater-than or equal to 60cm in diameter. At least 12 fir tress/ha greater-than or equal to 70 cm dbh should be retained to provide for future snag recruitment. A greater variety of silvicultural practices are acceptable in Zone 3, where maintenance of habitat diversity and travel corridors are the major objectives. Clearcuts in Zone 3 should be less-than or equal to 100m across with scattered groups of trees left within them, and travel corridors of at least 30% canopy closure should be left connecting important habitats.