The management of old-growth forest stands for wildlife requires identifying the wildlife species using such stands and also requires information on the features of stands that define the habitat of each species. The USFS (Region 5) and U.C. Berkeley have recently begun a cooperative study to develop such information for old-growth Douglas-fir in northwestern California. These studies required the development of sampling methods suitable for a wide variety of taxa (all vertebrates except fishes) over a large number of sites. All sampling is centered on 1 to 5 sample points located within each study stand, depending on stand size. Twelve ten-minute bird censuses are run at each point during each of 4, 3-month periods per year, using the variable-radius circular plot technique. Small mammals, reptiles, and amphibians are sampled at each point using combinations of live-traps and pitfalls. Larger mammals are surveyed using baited, smoked aluminum track plots, and we are attempting to survey bats using collapsible bat-traps. We measure vegetation characteristics' on 3 to 4, 0.04 ha circular elements randomly located near each sample point. Using these methods, we have identified 55 bird species, 19 mammals, 9 reptiles, and 7 amphibians in our preliminary surveys, as well as 94 plant taxa. Our methods may prove suitable for other studies including wildlife monitoring, elucidation of wildlife-habitat relationships, and general wildlife ecology research.
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