Environmental Assessment

AFFECTED ENVIRONMENT & ENVIRONMENTAL CONSEQUENCES CHAPTER 3
Table 3-2 Winter Mule Deer Population Estimates for the North Paulina Management Unit, 1990 to 2006 (Source: Glen
Ardt, Regional Habitat Biologist, ODFW).
Survey
Year
Winter
Population
Estimate
Population Index
(Percent of Management
Objective)
2006 2,900 53
2005 3,300 60
2004 3,300 60
2003 4,400 80
2002 4,400 80
2001 4,400 80
2000 5,000 90
1999 5,100 93
1998 5,400 98
1997 4,100 75
1996 4,000 73
1995 3,900 71
1994 3,300 60
1993 3,900 71
1992 4,700 85
1991 5,000 91
1990 4,600 83
Population trends for this management unit have been in decline since 1998 when the population
peaked at an estimated 5,400 animals or 98 percent of the management objective. Past declines have
been attributed to severe, prolonged winter weather; however the current trend does not have this
contributing agent. ODFW is concerned about impacts to deer in the North Paulina area including: past
wildfires such as the Skeleton, Evans, and 18 fires, private land development, mortality of migrating
deer in the Highway 20 and 97 corridors, disturbance by recreationists, livestock grazing, poaching, and
habitat alterations by fuels management activities, particularly in the wildland-urban interface. This
trend, as exhibited by the estimated population numbers, suggests that current situation appears to be
deteriorating for mule deer and additional negative effects, including excessive road/trail densities, will
potentially cumulatively add to the impacts on the population.
Existing Condition Hiding Cover - Hiding cover provides security for deer during hunting season,
from poachers, and from some predators. Hiding cover was defined using the definition developed by
Thomas (1979), which requires vegetation capable of hiding 90 percent of a standing adult deer or elk
from the view of a human at 200 feet or less.
Table 3-3 summarizes existing hiding cover across the planning area. Acceptable cover stands for the
purposes of this table and the subsequent analysis are defined as stands with 75 percent or more good
cover. Marginal cover acres were determined by using 50 percent of the gross cover acres with a
maximum of 50 percent of the cover acres being in non-cover types. Non-cover is defined as
vegetation or other features that would not hide at least 90 percent of a deer at 200 feet distance.
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