Environmental Assessment

AFFECTED ENVIRONMENT & ENVIRONMENTAL CONSEQUENCES CHAPTER 3
The lack of frequent, low intensity wildfire events over a prolonged period together with low recruitment
of large snags has significantly reduced the available habitat for this species over a large area. Activities
proposed by Opine and the other projects in the area would have a significant impact on reducing the
probability of future wildfires. However, the planned reintroduction of low intensity, prescribed fire in
many stands would mitigate this effect. Further, reduced stand densities in the preferred ponderosa pine
habitats would be beneficial together with increased sizes of trees and future snags. The Opine project
will treat approximately 2059 acres (35 percent of SS6 and 33 percent of SS7) of ponderosa pine habitat
in stages 6 and 7 by Alternative 2 and approximately 2560 acres (44 percent of SS6 and 37 percent of
SS7) by Alternative 3. Cumulatively, the action alternative effects on nesting and foraging habitats will
not lead to a trend toward Federal listing for the Lewis’ woodpecker.
Mammals
Bats
Townsend’s Big-eared Bat – The only MIS bat species present on the Deschutes National Forest is the
Townsend’s big-eared bat. Occurrence is documented on the Forest.
This species depends on caves for hibernation, raising young, and for day and night roosting. There is
one cave, Lavacicle, within the planning area. This cave does not have history of supporting many bats of
any species. There are extensive areas of lava within the planning area that could provide habitat. Some
of the known hibernacula within caves adjacent to the planning area are used by this species. Some small
lava formations occur within the planning area and bat usage of these areas due to their size would likely
be incidental. A few caves on the Bend-Fort Rock Ranger District harbor large winter hibernating
populations of this species, however, none are in the planning area.
This species forages in a broad range of forested conditions ranging from open savanna to fully stocked
conifer stands. Prey species are strongly associated with bitterbrush, ceanothus, and other shrub species.
Most foraging is suspected to occur within five (5) miles of day roost sites. Past research shows that
foraging along forested edges was most common and was apparently due to the availability both of prey
species, particularly moths, and protective habitat from predation.
The Central Oregon population, including those inhabiting the Deschutes National Forest, is estimated at
600 individuals (District survey records). Winter hibernacula counts have indicated a decline of
approximately 25 percent since 1986. The decline is probably due to a combination of factors including
the disturbance of hibernating bats, disturbance of maternity roosts, and the effects of past wildfires on
forage resources.
There are no identified direct or indirect effects identified for this species under Alternative 1. Assuming
no uncharacteristic wildfires, there would be no measurable effect on foraging habitat. However,
wildfire, particularly an uncharacteristic wildfire, would be expected to result in changes to existing shrub
densities, distributions, and structural components that could potentially negatively affect the quality,
quantity, and distribution of the prey base. This in turn could result in long-term reductions in resident
populations due to the lack of a suitable prey base.
Neither of the action alternatives would have measurable effects on this species. Mitigation measures
proposed for both alternatives limit effects to caves and rock outcroppings that provide, or could
potentially provide roosting habitat for this species.
Foraging habitat could be affected by the prescriptions for fuels treatments in shrub habitat. Alteration of
shrub habitat could influence prey availability within the planning area. A variety of shrub structure is
desirable in order to attract a variety of insect prey species. The action alternatives create a large amount
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