Final Environmental Impact Statement Rio de los Pinos Vegetation ...

Final Environmental Impact Statement Rio de los Pinos Vegetation Management Project
patchy distribution of deadfall, dead standing and newly regenerating trees and shrubs would
likely occur across the landscape. Some areas may continue to provide suitable habitat for those
species requiring closed-canopy forested areas and may even improve in quality as more coarse
woody debris becomes available and the understory vegetation is released.
Under this alternative, the proposed changes would be expected to mimic beetle infested areas in
the backcountry and wilderness areas adjacent to the analysis area, creating less of a habitat
mosaic across the landscape than either of the action alternatives.
Alternatives 2 and 3 -
The effects of timber harvesting upon sensitive species and their habitat are similar for both
action alternatives. The differences between the alternatives is more of a function of the number
of acres involved with each alternative with fewer treated acres resulting in less potential for
impacting sensitive species or their habitat than alternatives with more acres to be treated. To
summarize, the overall potential impacts upon the eight species are addressed below.
Sensitive Amphibians - There is a slight possibility that direct toad mortality could
occur during harvest operations through crushing of individuals, eggs, or underground burrows
by heavy equipment, although given the current scope of the project and lack of both current and
historic boreal toad documentation in the Analysis Area, this likelihood is low. Leopard frogs are
much more restricted to water than are boreal toads and as such are less impacted by the effects
of timber harvest activity, particularly given the harvest restriction in riparian areas (project
design criteria 2.5-5).
Removal of a large amount of overstory would change site conditions on the ground
and could impact boreal toad survival and reproduction by changing the microclimate in
the understory. Harvest would result in a more open canopy. More openings could impact toad
habitat by increasing the risk of predation and decreasing surface moisture. Woody debris are
used by toads as shelter. Regardless of the alternative selected, boreal toads would be expected to
have sufficient woody debris available for shelter, should they be present within the analysis
area.
Sensitive Avians - The proposed sales would result in fewer snags being available in the
future for nesting and in less structure in the form of woody debris for avian species and their
prey, particularly boreal owl’s main prey species - the red-backed vole. Removal of beetle
infested trees could degrade habitat for boreal owls in the immediate project site and may make
them more vulnerable to predation. However, the spatial distribution and concentration of trees
remaining should continue to provide suitable habitat for this species within the analysis area.
Protection measures for existing regeneration (see PDC 2.5-4), would protect some of the
smaller trees 8” dbh and below, that are currently used by boreal owls for roosting.
Harvested areas would fairly rapidly convert into more open habitat in the short term and this
impact would be beneficial to several avian species (goshawk and olive-sided flycatcher).
Through time, a patchy distribution of deadfall, dead standing and newly regenerating trees and
Chapter 3 – Affected Environment & Environmental Consequences Page 3-49