Fishers were studied concurrently at two sites in the coastal mountains of Shasta-Trinity National Forest in northwestern California, one where timber was heavily harvested, and the other lightly harvested.

"The main differences between the two sites were total length of logging roads and amount of forest harvested by presalvage logging." (369)

21 fishers were radio-collared, 169 telemetry locations in light harvested area, 260 locations in heavily harvested area. (372)

"Differences between habitat availability and use were primarily the result of selection by adult females." (372)

"We hypothesize that management practices that reduce mature conifer habitat and increase the proportion of hardwoods created suboptimal fisher habitat." (373)

"Our results indicate that within the [lightly harvested] site, fishers select areas with overhead canopy." (373)

"The effects of presalvage or selective logging are less apparent than those of clear-cutting, but these practices may have a greater impact on fishers over time, especially if the harvest involves large areas." (375)

"If our hypotheses prove correct, timber management practices that result in open stands, an abundance of hardwoods, and xeric conditions over large areas create conditions unsuitable for the maintenance of fisher populations. For fisher populations to be maintained, extensive clear-cutting of mature closed conifer forest should be minimized and selective cutting conducted so that adequate habitat is provided for all fisher age and sex classes." (375)