was excluded from subsequent analyses. The remaining eight species with disjunct ranges within
the assessment area are included in the analyses
(table 17). Note that some of these eight species
also may occur in one of the components listed
above (for example, whooping crane (Grus
americana) is also an endangered species). Wild
turkey (Meleagris gallopavo) was included in this
list because, although its disjunct populations result from introductions, the species has naturalized in these ranges (it is a “desired nonnative
vertebrate” in the parlance of National Forest
Management Act Regulations 38 CFR 219) and
is a sought-after species of positive economic
and social importance. The database and map for
this component show percentage of the area of
each 4th code HUC with coverage by any or all
of these species (fig. 50). A count of species by
4th code HUC was not used as the measure
because, interestingly, many of these species are
distributed as allopatric (nonoverlapping ranges),
so that a simple count of species by HUC was
not a sensitive measure of distribution. The mapped results suggest that HUCs important to disjunct vertebrate populations occur in Montana,
northern Idaho, central Idaho mountains, Snake
River plain in southwest Idaho, along the
Washington-Oregon border, and in the Cascade
Range in Oregon eastward into the high desert
and Klamath Basin.
Diversity components—Component (2b): Mapped locations of biodiversity hot spots (of plants
and animals combined)—This theme was derived
by overlaying the maps of centers of concentration of biodiversity of plants and animals (component 2d, below) and generating polygons where
at least three centers overlap (see Marcot and
others 1997 for further information on conditions
within each hot spot). The database and map for
this component show percentage of the area of
each 4th code HUC with coverage by any or all
polygons of biodiversity hot spots (fig. 51). Seven
biodiversity hot spots were identified in various
locations throughout the basin assessment area.
Component (2c): Mapped locations of species
rarity and endemism hot spots (of plants and
animals combined)—This theme was derived by
overlaying the maps of centers of concentration
of species rarity and endemism of plants and
animals (component 2d, below), and generating
polygons where at least three centers overlap (see
Marcot and others 1997 for further information
on conditions within each hot spot). The database
and map show percentage of the area of each 4th
code HUC with coverage by any or all polygons
(fig. 52). Twelve hot spots of species rarity and
endemism were identified in various locations,
mostly in southern Washington, in Oregon, and
southwestern Idaho. One major concentration
area is the Columbia River Gorge.
Component (2d): Mapped locations of centers
of concentration of biodiversity, and of species
rarity and endemism (for plants and animals
combined)—This theme was derived as polygons
mapped by expert panels during the panel meeting
on natural areas (see Marcot and others 1997 for
further information on methods). The database
and map show percentage of the area of each 4th
code HUC with coverage by any or all polygons
(fig. 53). Collectively, centers of concentration
for plants and animals occur in many locations
throughout the basin assessment area.
Ecological integrity goal 3: manage
for multiple ecological domains and
evolutionary timeframes
The overall concept of managing for multiple
ecological domains and evolutionary timeframes
entails ensuring that unique species assemblages
by geographic area are recognized and provided
for, and that the full trophic ladder occurs (represented here by distributions of large vertebrate
carnivores). Other components of this goal also
may entail ensuring that the full range of historic
and current habitat conditions and terrestrial communities are provided, including mid-scale and
site-specific microhabitats and substrates; however, these components were not mapped for this
analysis.
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Table 17—Examples of vertebrate species with disjunct distributions in the basin
assessment area, as mapped at the broad scale
Species
code
Scientific name
Common name
BUFWOO
Bufo woodhousii
Woodhouse’s toad
GRUAME
Grus ameriana
Whooping crane
LAMZON
Lampropeltis zonata
California mountain kingsnake
MELGAL
Meleagris gallopavo
Wild turkey
RANCLA
Rana clamitans
Green frog
RANSYL
Rana sylvatica
Wood frog
RHILEC
Rhinocheilus lecontei
Longnose snake
SONSEM
Sonora semiannulata
Ground snake
Legend
Species = 0%
Species 1 − 20%
Species > 20 − 40%
Species > 40 − 60%
Species > 60 − 80%
Species > 80 − 100%
4th field hydrologic
units
State boundaries
Basin boundary
ICBEMP
Figure 50—Percentage of each 4th-code hydrologic unit in the basin assessment area that includes
mapped distributions of vertebrate species with disjunct populations (see table 17 for list of species).
88