## Ecology

###### *T.M. Poston and M.R. Sackschewsky* {#t.m.-poston-and-m.r.-sackschewsky .unnumbered}

Ecology is an integrating discipline that defines the relationships
between organisms and their environment. Ecological evaluations are
organized by broad habitat type and include terrestrial and aquatic
ecosystems. Terrestrial ecosystems include upland and riparian/wetland
habitats. This section addresses the habitat, flora, and fauna found in
terrestrial (Section 4.5.1) and aquatic ecosystems (Section 4.5.2). A
third section addresses species formally listed as threatened,
endangered, or special status by federal and state agencies (Section
4.5.3).

Other descriptions of the ecology of the Hanford Site can be found in
Cadwell (1994); Downs et al. (1993); ERDA (1975); Jamison (1982);
Landeen (1996); Rogers and Rickard (1977); Sackschewsky and Downs
(2001); Watson et al. (1984); Weiss and Mitchell (1992); and Poston et
al. (2004).

### Terrestrial Ecology

Terrestrial ecosystems on the Hanford Site include upland and
riparian/wetland habitat. Upland habitat at Hanford is influenced by
arid climate and characterized by vegetation and wildlife adapted to hot
summers, cold winters, and low precipitation. Riparian habitat occurs
along bodies of water and is inhabited by plants requiring more water
than that provided by precipitation. Wetlands are areas where some open
water is present and soils and associated vegetation reflect the
presence of water. The upland habitat within the Hanford Site, located
within the Columbia Basin (Plateau) Ecoregion is predominantly
shrub-steppe (Stroms *et al*. 1997). Shrub-steppe ecosystems are
typified by a shrub overstory and a grass and forb understory
(Daubenmire 1970). Lichens and mosses, often times referred to as
"microbiotic or cryptogamic crust," provide a soil stabilizing growth on
undisturbed soils in the shrub-steppe ecosystem. The Columbia Basin
(Plateau) Ecoregion historically included over 6 million hectares (14.8
million acres) of steppe and shrub-steppe vegetation across most of
central and southeastern Washington, as well as portions of
north-central Oregon. Much of this land has been developed for
agriculture, industrial, and other developments.

In the early 1800s, the dominant vascular plants in the area were big
sagebrush underlain by perennial bunchgrasses and forbs. With the advent
of Euro-American settlement, livestock grazing and agricultural
production contributed to colonization by non-native plant species that
currently dominate portions of the landscape. Agriculture and livestock
production were the primary subsistence activities at the turn of the
20^th^ century. Although these activities ceased when the Hanford Site
was created in January 1943, remnants of past agricultural practices are
still evident. Many places on the Hanford Site are relatively free of
non-native species and are extensive enough to retain characteristic
populations of shrub-steppe plants and animals that are absent or scarce
in developed or fire-impacted areas of the ecoregion. Because of its
location, the Hanford Site provides important connectivity with other
undeveloped portions of the ecoregion.

Large areas of the Hanford Site have experienced recent range fires that
influence the vegetation composition and distribution of wildlife.
During 1984, a major fire burned across 800 km^2^ (310 mi^2^) of the
Hanford Site (Price et al. 1986). During 2000, a range fire burned
across the Hanford Site consuming most of the shrub-steppe habitat on
the Fitzner-Eberhardt Arid Lands Ecology Reserve Unit, a small section
of the McGee-Riverlands Unit, and other southwestern portions of the
Site. The fire burned a total of 655 km^2^ (250 mi^2^) of federal,
state, and private lands before it was controlled (BAER 2000).

These fires have altered the composition of the shrub-steppe habitat.
Much of the year 2000 burn was considered to be low severity. Low
severity refers to a burn that leaves the soil structure and seed bank
intact. The belowground portions of most perennial plants were unharmed
and have returned. Much of the burned area is in various stages of
recovery. Sagebrush may take considerably longer to recover than
perennial bunchgrass areas depending on the availability of seed in the
soil, severity of the burn, and the distance to other seed sources.
Reestablishment of mature sagebrush stands is likely to take a minimum
of 10 to 20 years. Some of the burned areas continue to be invaded by
non-indigenous plant species such as Russian thistle (*Salsola tragus,*
formerly *kali)* and tumble mustard (*Sisymbrium altissimum)*. In some
areas, efforts have been taken to reestablish big sagebrush (*Artemesia
tridentata*).

#### Vegetation

The Hanford Site contains some of the highest quality shrub-steppe
habitat in the state of Washington and the larger ecoregions in the
northwest. In some areas, unique and rare communities exist in spite of
past wildfires and the presence of non-native species introduced by man.
Because of the diversity of habitats on the Hanford Site, including a
relatively large elevation range of 1000 m, the riparian corridor, sand
dunes, and other special habitats, there is a high number of plant
species on site. A total of 727 species representing 90 families of
vascular plants are recorded for the Hanford Site (Sackschewsky and
Downs 2001). Of this total, 179 are non-native species. Cheatgrass
(*Bromus tectorum*) is the dominant non-native species. It is an
aggressive colonizer and has become well established across the Hanford
Site (Rickard and Rogers 1983). Hanford Site plants are adapted to low
annual precipitation (17 cm \[6.8 in.\]), low water-holding capacity of
the rooting substrate (sand), dry summers, and cold winters.

Microbiotic crusts are an important component of the shrub-steppe
communities found at Hanford. The microbiotic (or cryptogamic) crusts
generally occur in the top 1 to 4 mm (0.04 to 0.16 in.) of soil and are
composed of primarily algae, lichens, and mosses. These crusts are
formed by organisms and their by-products, creating a consolidated layer
of soil particles bound together by organic materials. Microbiotic
crusts are common in the semi-arid Columbia Basin, where the dominant
organism tends to be green algae (Johansen et al. 1993). The functions
of microbiotic crusts include soil stability and protection from
erosion; fixation of atmospheric nitrogen; nutrient contribution to
plants influencing soil-plant water relations; and increasing water
infiltration, seedling germination, and plant growth. The ecological
roles of microbiotic crusts depend on the relative cover of various
crustal components. Carbon inputs are higher when mosses and lichens are
present than when the crust is dominated by cyanobacteria. Nitrogen
inputs are higher with greater water infiltration. Soil surface
stability is related to cyanobacterial biomass as well as total moss and
lichen cover (Belnap et al. 2001). The lichen and mosses of the Hanford
Site were surveyed and evaluated by Link et al. (2000). They found 29
soil lichens in 19 genera and 6 moss species in 4 genera. Twelve (41
percent) lichen species are of the crustose growth form (flat and firmly
attached to the substrate), eight (28 percent) are squamulose (having
small, flat scales that do not adhere tightly to substrate), seven (24
percent) are foliose (having leaf-like lobes, attached in the center to
substrate by clusters of rhizomes), and two (7 percent) are fruticose
(plant-like growth attached at one point). More recent surveys have
found a total of 120 taxa of lichens and mosses on the Hanford Monument
lands surrounding the central portion of the Hanford Site (Evans et al.
2003).

Soll et al. (1999) conducted plant surveys on Fitzner-Eberhardt Arid
Lands Ecology Reserve Unit, the Wahluke Slope, central Hanford, and
riparian communities along the Columbia River shoreline from 1994
through 1997. These surveys tentatively identified 30 "potential"
terrestrial plant communities. Designation as a potential community
indicates a type of community that would exist in an area if it were
free of disturbance. In addition to characterizing potential plant
communities, Soll et al. (1999) found 112 populations/occurrences of 28
rare plant taxa on the Hanford Site. Rare plant taxa are defined by the
Washington Natural Heritage Program as plants that are followed because
of loss of habitat and dwindling populations. When combined with
observations preceding the 1994-1999 inventory, a total of 127
populations of 30 rare plant taxa have been documented on the Hanford
Site. A more general description of the vegetation cover types found on
Hanford, including shrublands, grasslands, microbiotic crust, tree
zones, and riparian habitat, follows.

**Shrublands**. Shrublands occupy the largest area in terms of acreage
and comprise seven of the nine major plant communities on the Hanford
Site (Sackschewsky and Downs 2001). Of the shrubland types,
sagebrush-dominated communities are predominant, with other shrub
communities varying with changes in soil and elevation. About 287 km^2^
(111 mi^2^) of shrub habitat dominated by big sagebrush was destroyed in
the year 2000 fire and is in various stages of shrub recovery.

Of the vegetation types found on the Hanford Site (Figure 4.5-1), those
with a shrub component (i.e., big sagebrush, threetip sagebrush
\[*Artemisia tripartita\]*, bitterbrush \[*Purshia tridentata\]*, gray
rabbitbrush \[*Ericameria nauseousa* previously *Chrysothamnus
nauseosus\]*, green rabbitbrush \[*Chrysothamnus viscidiflorus\]*, black
greasewood *\[Sarcobatus vermiculatus*\], winterfat \[*Krascheninnikovia
(Ceratoides) lanata*\], snow buckwheat \[*Eriogonum niveum\]*, and spiny
hopsage \[*Grayia (Atriplex) spinosa*\]) are considered shrub-steppe.
These stands typically have an understory dominated by bunchgrasses such
as bluebunch wheatgrass (*Pseudoroegnaria spicata* previously *Agropyron
spicatum)*, Sandberg's bluegrass (*Poa sandbergii \[secunda\])*,
needle-and-thread grass (*Hesperostipa comata* previously *Stipa
comata)*, Indian ricegrass (*Achnatherum* *hymenoides* previously
*Oryzopsis hymenoides)*, bottlebrush squirreltail (*Elymus elymoides*
previously *Sitanion hysterix*), and prairie junegrass (*Koeleria
cristata*), as well as a number of broad-leaf forbs. Heavily grazed or
disturbed areas often have an understory dominated by cheatgrass.
Heterogeneity of species composition varies with soil, slope, and
elevation. Vegetation types with a significant cheatgrass component are
generally of lower habitat quality than those with bunchgrass
understories. A list of common plant species in Hanford areas is
presented in Appendix B, Table B-1 and Sackschewsky and Downs (2001).

**Grasslands**. Most grasses occur as understory in shrub-dominated
plant communities. Because shrubs have been removed by fire in many
areas, there are large areas of grass-dominated communities on the
Hanford Site. Cheatgrass has replaced many native perennial grass
species and is well established in many low-elevation (less than 244 m
\[800 ft\]) and/or disturbed areas (Rickard and Rogers 1983, Soll et al.
1999). Of the native grasses that occur on the Hanford Site, bluebunch
wheatgrass occurs at higher elevations. Sandberg's bluegrass is widely
distributed throughout the Columbia Basin and the intermountain west.
Needle-and-thread grass, Indian ricegrass, and thickspike wheatgrass
(*Elymus* *macrourus* previously *Agropyron dasytachyum)* occur in sandy
soils and dune habitats. Species preferring more moist locations include
streambank or riparian wheatgrass (*Elymus* *lanceolatus* previously
*Agropyron dasystachyum* var. *smithii*), bentgrass (*Agrostis* spp.),
bluegrass (*Poa* spp.), meadow foxtail (*Alopecurus aequalis)*,
lovegrasses (*Eragrostis* spp.), and reed canarygrass (*Phalaris
arundinacea*) (DOE 2001a). A list of common plant species in grassland
areas is presented in Appendix B, Table B-1.

**Trees.** Within the past few hundred years, the Hanford Site upland
landscape had few trees and the Columbia River shoreline supported a few
scattered cottonwood (*Populus* spp.) or willows (*Salix* spp.).
Homesteaders and Manhattan Project construction workers planted trees in
association with agricultural areas and housing camps. Shade and
ornamental trees were planted in the 1950s around former military
installations and industrial areas on the Hanford Site. Currently,
approximately 23 species of trees occur on the Site. The most commonly
occurring species are black locust (*Robinia pseudo-acacia)*, Russian
olive (*Eleagnus angustifolia*), cottonwood (*Populus trichocarpa)*,
mulberry (*Morus alba)*, sycamore (*Platanus occidentalis)*, and poplar
(*Populus* spp.). Many of these non-indigenous species are aggressive
colonizers and have become established along the Columbia River (e.g.,
mulberry, poplar, Russian olive), serving as a functional component of
the riparian zone (DOE 2001a). Trees provide nesting habitat and cover
for many species of mammals and birds.

![](media/image1.jpeg){width="6.492361111111111in"
height="7.704166666666667in"}

> **Figure 4.5-1**. Distribution of Vegetation Types and Areas on the
> Hanford Site, Washington, before the Year 2000 Fire

![](media/image2.jpeg){width="6.489583333333333in"
height="8.455555555555556in"}

**Figure 4.5-1**. (cont'd)

**Hanford Operational Facilities and Retired Reactor Areas.** Yearly
vegetation surveys are conducted around many of the Hanford Site
operational facilities and retired reactor areas including facilities in
the 100, 200, and 300 Areas (Figure 4.0-1). In addition, there have been
several studies that examined the vegetation in the 200 Area Plateau
region and vegetation north of the 300 Area (Sackschewsky *et al*. 2001,
Brandt *et al*. 1993).

The 100 Area upland region consists of old agricultural fields dominated
by cheatgrass and tumble mustard. Scattered big sagebrush and gray
rabbitbrush also occur throughout the 100 Areas (Landeen et al. 1993).
An area of natural big sagebrush habitat near the 100-D Area experienced
a significant and apparently natural decline during the mid 1990s
(Cardenas et al. 1997). A total area encompassing 17.8 km^2^ (6.9 mi^2^)
was affected, and a central core area of 2.8 km^2^ (1.1 mi^2^)
experienced more than 80 percent mortality of sagebrush.

Waste management areas, reactors, and crib sites are generally either
barren or vegetated by non-native species, including Russian thistle,
tumble mustard, and cheatgrass. Most of the waste disposal and storage
sites are covered with non-native vegetation such as crested wheatgrass
or are kept in a vegetation-free condition with the use of herbicides to
prevent plant root intrusion to waste constituents. Russian thistle and
gray rabbitbrush that occur in these areas are deep rooted and have the
potential to function as a pathway to other parts of the ecosystem
(Landeen et al. 1993).

The undisturbed portions of the 200 Areas are characterized as
sagebrush/cheatgrass or sagebrush/Sandberg's bluegrass communities. The
dominant plants on the 200 Area Plateau are big sagebrush, rabbitbrush,
cheatgrass, and Sandberg's bluegrass (Sackschewsky and Downs 2001,
Sackschewsky et al. 2001). Most of the waste disposal and storage sites
are planted with crested or Siberian wheatgrass to stabilize surface
soil, control soil moisture, or displace more invasive deep-rooted
species like Russian thistle.

Vegetation surveys were conducted at the 300-FF-5 Operable Unit located
north of the 300 Area during 1992. The shrub-steppe vegetation community
in the unit is characterized as antelope bitterbrush/Sandberg's
bluegrass with an overstory of bitterbrush and big sagebrush and an
understory of cheatgrass and Sandberg's bluegrass (Brandt et al. 1993).

**Riparian and Wetland** **Areas**. Riparian areas are vegetated
wetlands, especially associated with rivers and streams, and include
shoreline areas along sloughs and backwaters. Wetlands also include
the shorelines of lakes, ponds, vernal pools temporarily formed by
melting snow in basalt outcrops, industrialized ponds, and irrigation
wasteways and ponds on the Wahluke Slope.

Riparian habitat that occurs in association with the Columbia River
includes riffles, gravel bars, backwater sloughs, and cobble shorelines.
These habitats occur infrequently along the Hanford Reach and have
acquired greater significance because of the net loss of wetland habitat
elsewhere within the region. Vegetation that occurs along the river
shoreline includes water smartweed (*Polygonum amphibium*), sedges
(*Carex* spp.), reed canary grass (*Phalaris arundinacea)*, bulbous
bluegrass (*Poa bulbosa*), common witchgrass (*Panicum capillare)*, and
large barnyard grass (*Echinochloa crusgalli)*. Rushes and sedges occur
along the shorelines of the Columbia River and at several sloughs along
the Hanford Reach. Trees include willow (*Salix* spp.), mulberry (*Morus
alba)*, and Siberian elm (*Ulmus pumila).* A list of common Hanford Site
riparian plants is provided in Appendix B, Table B-1.

Noxious weeds are also becoming established along the riparian zones of
the Hanford Reach. Purple loosestrife (*Lythrum salicaria)*, tamarisk
(*Tamarix parviflora*), yellow nutsedge (*Cyperus esculentus*), reed
canary grass, knapweed (*Centaurea* spp.), and yellow star thistle
(*Centaurea solstitialis)* are some of the more common species found
near or on wetlands on the Hanford Site. The Department of Energy and
the USFWS have an ongoing program to control populations of noxious
weeds with aerial applications of herbicides.

Some wetland habitat exists in the riparian zones of some of the larger
spring streams on the Fitzner-Eberhardt Arid Lands Ecology Reserve Unit.
These are not extensive and usually amount to less than 0.01 km^2^
(0.004 mi^2^) in size, although the riparian zone along Rattlesnake
Springs is probably about 2 km (1.2 mi) in length and consists of peach
leaf willows, cattails, and other non-indigenous plants. Rattlesnake and
Snively Springs support highly diverse biological communities (Cushing
and Wolf 1984) that include bulrush (*Scirpus* spp.), spike rush
(*Eleocharis* spp.), and cattail (*Typha latifolia)*. Watercress
(*Rorippa nasturtium-aquaticum)*, which persists at these sites, is also
abundant for a large portion of the year. In the past 30 years,
introduced trees and shrubs have become established in the riparian zone
along these springs. The riparian transects associated with Snively and
Rattlesnake Springs were greatly impacted by the year 2000 fire (BAER
2000) (Figure 4.5-2).

Other wetland habitats can be found within the Saddle Mountain National
Wildlife Refuge Unit and the Wahluke Unit. These two areas encompass all
the lands extending from the north bank of the Columbia River northward
to the Hanford Site boundary and east of the Columbia River from Ringold
Springs north to Highway 24 in Adams County. Wetland habitat in these
areas consists of fairly large pond habitat resulting from irrigation
runoff. These ponds have extensive stands of cattails and other emergent
aquatic vegetation surrounding the open-water regions (Figure 4.5-1).
They are extensively used as nesting sites by waterfowl and support
populations of warm water fish that have been introduced by the
irrigation network.

**Other Habitats**. Basalt outcrops, river bluffs, dunes, and islands
occur on the Hanford Site and their unique qualities create habitat for
a distinct assemblage of vegetation (DOE 2001a). The top of Rattlesnake
Mountain, Umtanum Ridge, Gable Butte, and Gable Mountain include rock
outcrops and have thin rocky soils. Plant communities dominated by thyme
buckwheat (*Eriogonum thymoides*) and Sandberg's bluegrass most often
occupy these basalt outcrops.

The White Bluffs border the Columbia River along the northern shoreline
from RM 376 downstream to RM 356 presenting a steep environment with
sparse and patchy vegetation. Dense patches of Indian ricegrass occupy
the top of the bluff area. Primary shrubs found on the slopes of the
bluff are greasewood and spiny hopsage. Bluff areas provide habitat for
sensitive species (e.g., Hoover's desert parsley \[*Lomatium
tuberosum*\] and the White Bluffs bladderpod \[*Lesquerella
tuplashensis*\], a Washington State endangered plant).

Bitterbrush and Indian ricegrass dominate a large dune area north of the
Energy Northwest complex along the Columbia River shoreline (Figure
4.5-1). The terrain of the dune habitat rises and falls between 3 and
5 m (10 and 16 ft) above ground level, creating areas that range from
2.5 to several hundred acres in size (U.S. Department of the Army 1990).
The dunes vegetation consists of a mosaic of shrubs and grasses,
primarily bitterbrush and gray and green rabbitbrush with understory
forbs and grasses that include scurfpea (*Psoralea lanceolata)*,
needle-and-thread grass, and thickspike wheatgrass. Smaller dunes
containing basalt grains that impart a dark color to the sand are found
near the 100-F Area and westward across the Site north of Gable
Mountain. As a result of the fire that occurred during 2000, temporary
dunes have formed along State Route 240 east to the 200 West Area and
Army Loop Road. These burnt areas are in various stages of recovery.

![](media/image3.jpeg){width="5.898611111111111in" height="7.6875in"}

> **Figure 4.5-2**. Area of Hanford Site, Washington, Burned as a Result
> of the June 27 to July 2, 2000, Wildfire

Island habitat accounts for approximately 4.74 km^2^ (1.8 mi^2^) (Hanson
and Browning 1959) and 64.3 km (39.9 mi) of river shoreline within the
main channel of the Hanford Reach (Figure 4.5-3).^(^[^1]^)^ DOE owns and
administers the upland portions of Locke Island (RM 371-373.5) and
Wooded Island (RM 348-351). The Washington State Department of Natural
Resources manages the shorelines of Locke and Wooded islands. Landslides
caused by rotational slumping in the White Bluffs area caused
accelerated erosion of Locke Island by the Columbia River. Shoreline
riparian vegetation on the islands includes willow, poplar, Russian
olive, and mulberry. Before regulation of river flows by dams, trees
were generally not found along river shoreline habitat, with the
exception of small willows and a few juniper trees near the 100-B/C Area
and Riverlands. The most common tree to establish itself along the
shoreline is mulberry. Species occurring on the island interior include
buckwheat, lupine, mugwort, thickspike wheatgrass, giant wildrye,
yarrow, and cheatgrass (Warren 1980).

West Lake and its immediate basin represent a habitat that is
characterized by highly saline conditions (Poston et al. 1991). These
conditions occur most likely from the evaporation of water from the pond
and the accumulation of dissolved solids during the early years of
operations on the Hanford Site. West Lake is now classified as a waste
site under the Comprehensive Environmental Restoration, Compensation,
and Liability Act of 1980 (CERCLA) (42 USC 9601, *et seq*.). Water
levels of the pond fluctuate with wastewater discharge levels in the 200
Areas. Dominant plants at West Lake include salt grass (*Distichlis
stricta*), plantain (*Plantago* species), and salt rattlepod (*Swainsona
salsula*). Bulrush (*Scirpus* species) grows along the shoreline;
however, the water in the lake is too saline to support aquatic
macrophytes. The water level of West Lake has dropped following the
decrease in water discharged to the ground in the 200 Areas during the
early 1990s, exposing large sections of saline mud flats and salt
deposits along the shoreline.

A series of vegetation/land cover maps (Appendix C) were prepared to
provide information on available habitat in support of a review of
ecological data for clean-up activities along the Columbia River
shoreline (Poston et al. 2004). These maps represent the best available
information on vegetation cover types and plant associations located in
specific areas at the time the data were collected (from 1997 to 2004).
Vegetation communities are subject to change depending on climatic
conditions, physical disturbance, progress with clean-up, and natural
recruitment and succession at the sites. For descriptions of upland
vegetation the reader is referred Sackschewsky and Downs (2001); for
descriptions of riparian vegetation, see Section 8.0 of the Hanford Site
Annual Environmental Report (Poston et al. 2004).

The maps in Appendix C are subsets of maps originally constructed using
aerial photography and limited ground surveys and should be appropriate
for use in project planning. Maps are updated as information becomes
available. However, the extent and boundaries of the vegetation cover
types may change over time and the accuracy of the boundaries is further
limited by the resolution of the source data used for mapping (usually
+/- 20 to 30 m \[66 to 98 ft\] depending on the source). Reference to
these maps cannot be used in place of project-specific site biological
surveys for compliance. To access the most recent vegetation maps
maintained for the areas of the Hanford Site, visit the PNNL project web
site for the Ecological Monitoring and Compliance (EMC) Project
(<http://www.pnl.gov/ecomon>) or request updated maps from the EMC
Project at PNNL.

![](media/image4.png){width="6.488888888888889in"
height="7.495138888888889in"}

> **Figure 4.5-3**. Columbia River Islands in the Vicinity of the
> Hanford Site, Washington

#### Wildlife

The characterization of Hanford Site wildlife includes descriptions of
mammals, birds, reptiles, amphibians, and insects. Approximately 300
species of terrestrial vertebrates have been observed on the Hanford
Site. The species list includes approximately 46 species of mammals
(Appendix B, Table B-2), 246 species of birds (Appendix B, Table B-3), 6
species of amphibians, and 10 species of reptiles (Appendix B, Table B-
4) (Soll and Soper 1996, Brandt et al. 1993). From 1991 to 1993, surveys
for birds, mammals, insects, and vegetation were conducted at several of
the 100 and 300 Area operable units (Brandt et al. 1993, Landeen et al.
1993). Soll et al. (1999) recently summarized its observations of birds
and mammal surveys. These surveys did not account for all of the species
that have been documented historically on the Hanford Site. For example,
221 species of birds were observed in the bird surveys of The Nature
Conservancy's biodiversity 4-year effort (Soll et al. 1999). This number
falls short of the 238 species identified historically (Landeen et al.
1992). By combining the 1994-1999 list of The Nature Conservancy with
the site list (Landeen et al. 1992), a total of 258 species of birds
have been documented on the Hanford Site (Soll et al. 1999). There are
144 bird species considered common to the Hanford Site (Appendix B,
Table B 3). Site wildlife communities are generally associated with
specific vegetation communities.

**Shrub-steppe and Grassland Wildlife**. The shrub and grassland habitat
of the Hanford Site supports many groups of terrestrial wildlife.
Species include large animals like Rocky Mountain elk (*Cervus elaphus)*
and mule deer (*Odocoileus hemionus)*; predators such as coyote (*Canis
latrans)*, bobcat (*Lynx rufus)*, and badger (*Taxidea taxus)*; and
herbivores including deer mice (*Peromyscus maniculatus)*, harvest mice
(*Riethrodontonomys megalotis)*, ground squirrels (*Spermophilus* spp.),
voles (*Lagurus* spp., *Microtus* spp.), and black-tailed jackrabbits
(*Lepus californicus)*. The most abundant mammal on the Hanford Site is
the Great Basin pocket mouse (*Perognathus parvus)*. Many of the rodent
species and some predators (badgers) construct burrows on the site.
Other non-borrowing animals including cottontails (*Sylvilagus
nutalli)*, jackrabbits, snakes, and burrowing owls (*Athene
cunicularia)* may utilize abandoned burrows of other animals.

There was a reported sighting of a cougar (*Felis concolor)* on
Fitzner-Eberhardt Arid Lands Ecology Reserve Unit by experienced
biologists during the elk relocation effort in March 2000, supplementing
anecdotal accounts of other observations of the presence of cougars at
the Hanford Site.

Mule deer rely mainly on shoreline vegetation and bitterbrush shrubs for
browse (Tiller et al. 1997). Elk, which are more dependent on open
grasslands for forage, seek the cover of sagebrush and other shrub
species during the summer months. Elk first appeared on the Hanford Site
during 1972 (Fitzner and Gray 1991), and have increased from
approximately 8 animals observed in 1975 to approximately 900 in 1999.
The Rattlesnake Hills herd of elk that inhabits the Hanford Site
primarily occupies Fitzner-Eberhardt Arid Lands Ecology Reserve Unit and
private lands that adjoin the reserve to the south and west. They are
occasionally seen on the 200 Area Plateau and have been sighted at the
White Bluffs boat launch on the Hanford Site. The herd tends to
congregate on Fitzner-Eberhardt Arid Lands Ecology Reserve Unit in the
winter and disperses during the summer months to higher elevations on
the reserve, private land to the west, and the Yakima Training Center.
Efforts were taken in March 2000 to remove and relocate about 200 elk
from the Fitzner-Eberhardt Arid Lands Ecology Reserve Unit and another
31 elk were removed during 2002. Special hunts adjacent to the Hanford
Site during 2000 accounted for the removal of 207 additional elk. The
fire in June 2000 temporarily destroyed nearly all the elk forage on
Fitzner-Eberhardt Arid Lands Ecology Reserve Unit. The herd moved onto
unburned private land west of the site, to unburned areas on central
Hanford, and along the Columbia River near the 100-B/C and 100-K Areas.
Elk have returned to burned areas as the vegetation recovered.

Shrub-steppe and grassland provide nesting and foraging habitat for many
passerine (i.e., perching) bird species. Surveys conducted during 1993
(Cadwell 1994) reported the occurrence of western meadowlarks
(*Sturnella neglecta)* and horned larks (*Eremophila alpestris)* more
frequently in shrub-steppe habitats than in other habitats on the
Hanford Site. Soll et al. (1999) reported a total of 41 species that are
considered steppe or shrub-steppe habitat dependent. Long-billed curlews
(*Numenius americanus*) and vesper sparrows (*Pooecetes gramineus)* were
also noted as commonly occurring species in shrub-steppe habitat.
Species that are dependent on undisturbed shrub habitat include sage
sparrow (*Amphispiza belli)*, sage thrasher (*Oreoscoptes montanus)*,
and loggerhead shrike (*Lanius ludovicianus)*. Both the sage sparrow and
loggerhead shrike tend to roost and nest in sagebrush or bitterbrush
that occurs at lower elevations (DOE 2001a). Ground-nesting species that
occur in grass-covered uplands include long-billed curlews, western
meadowlark, and burrowing owls.

Common upland gamebird species that occur in shrub and grassland habitat
include chukar (*Alectoris chukar)*, partridge (*Perdix perdix)*,
California quail (*Callipepla californica)*, and ring-necked pheasant
(*Phasianus colchicus)*. Chukars are most numerous in the Rattlesnake
Hills, Yakima Ridge, Umtanum Ridge, Saddle Mountain, and Gable Mountain
areas of the Hanford Site. Less common species include greater sage
grouse (*Centrocercus urophasianus*), and scaled quail (*Callipepla
squamata*). Greater sage grouse were historically abundant on the
Hanford Site; however, populations have declined since the early 1800s
because of the conversion of sagebrush-steppe habitat to farmland,
hunting, and destruction of habitat by range fires. Surveys conducted by
the Washington Department of Fish and Wildlife and PNNL during 1993 and
biodiversity inventories conducted in 1997 (Soll et al. 1999) did not
observe greater sage grouse in the sagebrush-steppe habitat at
Fitzner-Eberhardt Arid Lands Ecology Reserve Unit. Greater sage grouse
were observed on Fitzner-Eberhardt Arid Lands Ecology Reserve Unit
during 1999 and 2000.^(^[^2]^)^ A greater sage grouse was killed by an
automobile near the 100-F area in the spring of 2003; however, this is
considered an abnormal occurrence for this part of the Hanford Site. The
fire in June 2000 destroyed potential greater sage grouse habitat, and
it is unlikely that greater sage grouse will return until the vegetation
has recovered to a point where it can support them.

Among the more common raptor species that use shrub and grassland
habitat are the ferruginous hawk (*Buteo regalis)*, Swainson's hawk (*B.
swainsoni)*, and red-tailed hawk (*B. jamaicensis)*. Northern harriers
(*Circus cyaneus)*, sharp-shinned hawks (*Accipiter striatus)*,
rough-legged hawks (*B. lagopus)*, and golden eagles (*Aquila
chrysaetos)* also occur in this habitat, although infrequently. During
1994, nesting by red-tailed, Swainson's, and ferruginous hawks was known
to occur in 41 nests located across the Hanford Site on high voltage
transmission towers, trees, cliffs, and basalt outcrops. Since the
mid-1990s, the number of breeding ferruginous hawks (a Washington State
threatened species) on the Hanford Site has increased, due, in part, to
their use of steel powerline towers for nesting in the open grass and
shrub-steppe habitats.

The side-blotched lizard (*Uta stansburiana)* is the most abundant
reptile species occurring on the Hanford Site. Short-horned (*Phrynosoma
douglassii)* and sagebrush (*Sceloporus graciosus*) lizards are also
found on the Hanford Site, but occur infrequently. The most common snake
species include gopher snake (*Pituophis melanoleucus)*, yellow-bellied
racer (*Coluber constrictor)*, and western rattlesnake (*Crotalus
viridis)*.

Many species of insects occur throughout all habitats on the Hanford
Site. Butterflies, grasshoppers, and darkling beetles are among the most
conspicuous of the about 1500 species of insects that have been
identified from specimens collected on the Hanford Site (Soll et al.
1999). The actual number of insect species occurring on the Hanford Site
may reach as high as 15,500. A total of 1509 species-level
identifications were completed during 1999 and 500 more are expected.
Recent surveys included the collection of 40,000 specimens and have
resulted in the identification of 43 new taxa and 142 new findings in
the state of Washington (Soll et al. 1999). The high diversity of insect
species on the Hanford Site reflects the size, complexity, and
relatively undisturbed quality of the shrub-steppe habitat.

**Riparian Wildlife**. Riparian areas provide nesting and foraging
habitat and escape cover for many species of birds and mammals.
Shoreline riparian communities are seasonally important for a variety of
species. Willows trap food for waterfowl (e.g., Canada geese \[*Branta
canadensis*\]) and birds that use shoreline habitat (e.g., Forster's
tern \[*Sterna forsteri\]*) as well as providing nesting habitat for
passerines (e.g., mourning doves \[*Zenaida macroura*\]). Terrestrial
and aquatic insects are abundant in emergent grasses and provide food
for fish, waterfowl, and shorebirds.

Mammals occurring primarily in riparian areas include rodents, bats,
furbearers (e.g., mink \[*Mustela vison*\] and weasel \[*Mustela*
spp*.*\]), porcupine (*Erithizon dorsatum)*, raccoon (*Procyon lotor)*,
skunk (*Mephitis mephitis)*, and mule deer. Beavers (*Castor
canadensis)* rely on shoreline habitat for dens and foraging. River
otters (*Lutra canadensis)* have been observed infrequently in the
Hanford Reach. During the summer, mule deer rely on riparian vegetation
for foraging. Mule deer use Columbia River islands for fawning and
nursery areas. Beaver and muskrat (*Ondatra zibethica)* rely on
shoreline habitat for dens and foraging. The Columbia River and
Rattlesnake Springs provide foraging habitat for bats including Yuma
myotis (*Myotis yumanensis*), small-footed myotis (*Myotis subulatus)*,
silver-haired bats (*Lasionycteris octivagans)*, and pallid bats
(*Antrozous pallidus)*, all of which feed on emergent aquatic insects
(Becker 1993).

Common bird species that occur in riparian habitats include red-winged
blackbird (*Agelaius phoeniceus)*, American robin (*Turdus
migratorius)*, black-billed magpie (*Pica pica)*, song sparrow
(*Melospiza melodia)*, and dark-eyed junco (*Junco hyemalis)* (Cadwell
1994). Upland gamebirds that use this habitat include ring-necked
pheasants and California quail. Predatory birds include common barn owl
(*Tyto alba)* and great horned owl (*Bubo virginianus)*. Burrowing owls
have been observed on some of the islands in the Columbia River. Species
known or expected to nest in riparian habitat are Brewer's blackbird
(*Euphagus cyanocephalus)*, mourning dove, black-billed magpie, northern
oriole (*Icterus galbula)*, lazuli bunting (*Passerina amoena)*, eastern
kingbird (*Tyrannus tyrannus*), western kingbird (*Tyrannus
verticalis)*, and western wood peewee (*Contopus sordidulus)*. Bald
eagles (*Haliaeetus leucocephalus)* have wintered on the Hanford Site
since 1960. Great blue herons (*Ardea herodias*) and black-crowned night
herons (*Nycticorax nycticorax)* are associated with trees in riparian
habitat along the Columbia River and use groves or individual trees for
perching and nesting. On occasion, great blue herons have constructed
nests in the large metal powerline towers that are present on the shores
of the Columbia River.

The Hanford Site is located in the Pacific Flyway, and the Hanford Reach
serves as a resting area for neotropical migrant birds, migratory
waterfowl, and shorebirds (Soll et al. 1999). The area between the Old
Hanford Townsite and Vernita Bridge is closed to recreational hunting,
and large numbers of migratory waterfowl find refuge in this portion of
the river. Other species observed during this period include American
white pelicans (*Pelecanus erythrorhynchos)*, egrets (*Casmerodius
albus)*, double-crested cormorants (*Phalacrocorax auritus)*, coots
(*Fulica americana*), and common loons (*Gavia immer)*.

Along with the reptiles and insects identified in the grasslands
discussion, six amphibians have been identified on the site. The Great
Basin spadefoot toad (*Scaphiopus intermontanus)*, western toad (*Bufo
boreas*), Woodhouse's toad (*Bufo woodhousei)*, Pacific tree frog (*Hyla
regilla)*, tiger salamander (*Ambystoma tigrinum)*, and bullfrog (*Rana
catesbeiana)* are the only amphibians found in close proximity to water
on the Hanford Site (Soll et al. 1999, Brandt et al. 1993).

**Wildlife Occurring in Other Hanford Site Habitats**. Bluffs provide
perching, nesting, and escape habitat for several bird species on the
Hanford Site. The White Bluffs and Umtanum Ridge provide nesting habitat
for prairie falcons (*Falco mexicanus)*, red-tailed hawks, cliff
swallows (*Hirundo pyrrhonota)*, bank swallows (*Riparia riparia)*, and
rough-winged swallows (*Stelgidopteryx serripennis*). In the 1970s and
'80s, Canada geese used the lower elevations of the White Bluffs for
nesting and brooding. Bald eagles use the White Bluffs for roosting.
Bluff areas provide habitat for sensitive species (e.g., peregrine
falcon \[*Falco peregrinus*\]) that otherwise may be subject to impact
from frequent or repeated disturbance. Trees that do not normally occur
in arid steppe habitat supply nesting, perching, and roosting sites for
many birds. Consequently, herons and raptors, such as ferruginous and
Swainson's hawks, can use trees for breeding in areas that previously
did not support breeding populations. Ferruginous hawks also nest on
electrical transmission line towers. These occurrences of raptor nesting
in non-native trees occur in upland areas as well as riparian zones
along the Hanford Reach.

Dune habitat is unusual in its association with the surrounding
shrub-steppe vegetation type. The individuality of the dunes is noted in
its vegetation component as well as its geologic formation. The Hanford
dunes, located on the eastern border of the Site, provide habitat for
mule deer, burrowing owls, and coyotes as well as many transient
species. In contrast, the dunes in west central Hanford, formed as a
result of the fire in June 2000, may be temporary and could disappear
once vegetation is reestablished.

Islands provide resting, nesting, and escape habitat for waterfowl and
shorebirds. Use of islands for nesting by Canada geese has been
monitored since 1950. The suitability of habitat for nesting Canada
geese is attributed to restricted human use of islands during the
nesting season, suitable substrate, and adequate forage and cover for
broods (Eberhardt et al. 1989). The nesting population fluctuates
annually. Since the early 1990s, geese have used the downstream islands
in the Hanford Reach for nesting as a result of coyote predation in the
upper Reach islands. Islands also accommodate colonial nesting species
including California gulls (*Larus californicus)*, ring-billed gulls
(*Larus delawarensis*), and Forster's terns (*Sterna forsteri)*. Island
areas ranging from 0.1 to 0.2 km^2^ (0.05 to 0.08 mi^2^) accommodate
colonial nesting species that may range in population size up to 2000
individuals.

### Aquatic Ecology

Aquatic resources on the Hanford Site are primarily associated with the
Columbia River. The river crosses the Hanford Site entering at the
northwest corner of the site, traveling eastward and then turning south,
forming the eastern boundary of the site. The Columbia River and
associated riparian zones provide habitat for numerous wildlife and
plant species. The area known as the Hanford Reach, the Columbia River
from Priest Rapids Dam (river mile \[RM\] 397) to McNary Pool (RM 346)
is the last non-impounded, non-tidal segment of the Columbia River in
the United States. Several small intermittent spring/streams are also
found on the site and, with their unique riparian habitat, provide a
break in the vast expanses of shrub-steppe habitat that dominate the
Hanford Site.

#### Columbia River

The Columbia River is the dominant aquatic ecosystem on the Hanford Site
and supports a large and diverse community of plankton, benthic and
lotic invertebrates, fish, and other communities. Large rivers, like the
Columbia River with its series of large reservoirs, contain significant
populations of primary energy producers (e.g., algae and plants) that
contribute to the biota's basic energy requirements.

Phytoplankton (free-floating algae) and periphyton (sessile algae) are
abundant in the Columbia River and provide food for herbivores such as
immature insects. Plankton populations in the Hanford Reach are
influenced by communities that develop in the reservoirs of upstream
dams, particularly Priest Rapids Reservoir, and by the manipulation of
water levels by dam operations in upstream and downstream reservoirs.
Phytoplankton and zooplankton populations at the Hanford Site are
largely transient, flowing from one reservoir to another. With the
relatively rapid flow of the Columbia River, there is generally
insufficient time for characteristic endemic groups of phytoplankton and
zooplankton to develop in the Hanford Reach.

**Phytoplankton**. Phytoplankton species identified from the Hanford
Reach include diatoms, golden or yellow-brown algae, green algae,
blue-green algae, red algae, and dinoflagellates. Studies show diatoms
are the dominant algae in the Columbia River phytoplankton, usually
representing more than 90 percent of the populations. The main genera
include *Asterionella, Cyclotella, Fragilaria, Melosira,
Stephanodiscus*, and *Synedra* (Neitzel et al. 1982a). These are typical
of those forms found in lakes and ponds and originate in upstream
reservoirs. A number of algae found as free-floating species in the
Hanford Reach of the Columbia River are actually derived from the
periphyton; they were detached and suspended by currents and frequent
fluctuations of the water level.

Cushing (1967a) found peak concentrations of phytoplankton occurred in
April and May, with a secondary peak in late summer/early autumn. The
spring pulse in phytoplankton density was probably related to increasing
light and water temperature rather than to availability of nutrients, as
phosphate and nitrate nutrient concentrations are never limiting.
Minimum numbers were present in December and January. Green algae
(*Chlorophyta*) and blue-green algae (*Cyanophyta*) occur in
phytoplankton communities during warmer months but in substantially
fewer numbers than diatoms. Diversity indices, carbon uptake, and
chlorophyll concentrations for the phytoplankton show similar seasonal
trends (Neitzel et al. 1982a, Wolf et al. 1976).

**Periphyton**. Communities of periphytic species or "benthic
microflora" develop on suitable solid substrate wherever there is
sufficient light for photosynthesis and adequate currents to prevent
sediment from covering the colonies. Operation of Priest Rapids Dam
results in frequent river level fluctuations. These fluctuations result
in exposed shoreline areas that do not allow for the establishment of
viable and persistent periphyton communities in shoreline areas
inundated by water at flows greater than 1310 m^3^/s (46,300 cfs)
(Tiller and Downs 2004). Cushing (1967b) observed peaks of production to
occur in spring and late summer. Dominant genera are the diatoms
*Achnanthes, Asterionella, Cocconeis, Fragilaria, Gomphonema, Melosira,
Nitzchia, Stephanodiscus*, and *Synedra* (Beak Consultants Inc. 1980,
Neitzel et al. 1982a, Page and Neitzel 1978, Page et al. 1979).

**Macrophytes**. Macrophytes are sparse in the Columbia River because of
strong currents, rocky bottom, and frequently fluctuating water levels.
Rushes (*Juncus* spp.) and sedges (*Carex* spp.) occur along shorelines
of the slack-water areas such as White Bluffs Slough below the 100-H
Area, the slough area downstream of the 100-F Area, and the Hanford
Slough. Reed canary grass (*Phalaris arundinacea*) is a common
non-native species found along shoreline areas. Macrophytes are also
present along gently sloping shorelines that are subject to flooding
during the spring freshet and daily fluctuating river levels (downsteam
of Coyote Rapids and the 100-D Area). Commonly found plants include
duckweed (*Lemna* sp*.*) and the native rooted pond weeds *(Potamogeton*
sp. and *Elodea canadensis*). Where they exist, macrophytes have
considerable ecological value. They provide food and shelter for
juvenile fish and spawning areas for some species of warm-water game
fish. Eurasian milfoil (*Myriophyllum spicatum*), an introduced
macrophyte, has increased to nuisance levels since the late 1980s and
may encourage increased sedimentation of fine particulate matter.

**Zooplankton**. The zooplankton populations in the Hanford Reach of the
Columbia River are generally sparse. Studies by Neitzel et al. (1982b)
indicate crustacean zooplankters were dominant in the open-water
regions. Dominant genera were *Bosmina, Diaptomus*, and *Cyclops*.
Densities were lowest in winter and highest in the summer, with summer
peaks dominated by *Bosmina*, ranging up to 160,650 organisms/m^3^ (4500
organisms/ft^3^). Winter densities were generally less than 1785
organisms/m^3^ (50 organisms/ft^3^). *Diaptomus* and *Cyclops* dominated
in winter and spring, respectively (Neitzel et al. 1982b).

**Benthic Organisms**. Benthic organisms are found either attached to or
closely associated with the substratum. All major freshwater benthic
taxa are represented in the Columbia River. Insect larvae such as
caddisflies (*Trichoptera*), midge flies (*Chironomidae*), and black
flies (*Simuliidae*) are dominant. Dominant caddisfly species are
*Hydropsyche cockerelli, Cheumatopsyche campyla*, and *C. enonis*. Other
benthic organisms include clams (*Corbicula* spp., *Anodontia* spp.),
limpets (*Fisherola* spp.), snails (*Physa* spp.), sponges (*Spongilla*
spp.), and crayfish (*Astacus trowbridgii*). Operation of Priest Rapids
Dam results in frequent river level fluctuations. These fluctuations
result in exposed shoreline areas during low-flow periods that do not
allow for the establishment of persistent benthic communities. Clams and
crayfish have difficulty in establishing populations in stranded
shoreline areas that are frequently left dewatered by river level
fluctuations. Species with rapid life cycles are less likely to be
impacted by river fluctuations.

Early Hanford studies found crayfish numbers in shallow water areas
ranged from 0.02 to 0.10 individuals/m^2^ (0.2 to 1.1 individuals/ft^2^)
of river bottom, with a diet primarily of vegetation (Coopey 1953),
while insect larvae numbers were sometimes as high as 185.8/m^2^
(2000/ft^2^) (Davis and Cooper 1951). Peak larval insect densities are
found in late fall and winter, and the major emergence is in spring and
summer (Wolf 1976). Stomach contents of fish collected in the Hanford
Reach from June 1973 through March 1980 revealed that benthic
invertebrates were important food items for nearly all juvenile and
adult fish. There was a correlation between food organisms in the
stomach contents and those in the benthic and invertebrate drift
communities. A survey by Soll et al. (1999) identified 21 new taxa of
aquatic invertebrates in the Hanford Reach bringing the total number of
aquatic invertebrate taxa to 151.

**Fish**. Gray and Dauble (1977) listed 43 species of fish in the
Hanford Reach of the Columbia River. The brown bullhead (*Ictalurus
nebulosus*), collected since 1977, and the blue catfish (*Ictalurus
furcatus*) listed by Washington Department of Fish and Game, brings the
total number of fish species identified in the Hanford Reach to 45
(Appendix B, Table B-5). Sixteen of these 45 species are introduced
(Wydoski and Whitney 1979). Of these species, Chinook salmon
(*Oncorhynchus tshawytscha)*, sockeye salmon (*Oncorhynchus nerka)*,
coho salmon (*Oncorhynchus kisutch)*, and steelhead trout (*Oncorhynchus
mykiss)* use the river as a migration route to and from upstream
spawning areas and are of the greatest economic importance.
Additionally, fall Chinook salmon and steelhead trout spawn in the
Hanford Reach. The relative contribution of up-river bright stocks to
fall Chinook salmon runs in the Columbia River increased from about 24
percent of the total in the early 1980s, to 50 to 60 percent of the
total by 1988 (Dauble and Watson 1990). Inundation of other mainstream
Columbia spawning grounds by dams has increased the relative importance
of the Hanford Reach to fall Chinook salmon production in the Columbia
and Snake rivers (Watson 1970, 1973; Dauble and Watson 1997). Operation
of Priest Rapids Dam can result in frequent river level fluctuations
exposing shoreline and cobble bars during low-flow periods. In recent
years, Priest Rapids Dam has operated with an objective to stabilize
fall river levels to prevent salmon from spawning in areas that will be
exposed at low river flow during the winter, thus protecting salmon
redds from desiccation and temperature extremes. Fall Chinook salmon
redd surveys have been conducted in Hanford Reach since 1950. There are
presently 10 areas identified in the Hanford Reach (Figure 4.5.4) that
support salmon spawning (Dauble and Watson 1997, Poston *et al*. 2004).

The steelhead fishery in the Hanford Reach (Highway 395 Bridge to Priest
Rapids Dam) consists almost exclusively of summer-run fish. The
Washington State Department of Fish and Wildlife (WDFW)

![](media/image5.png){width="6.506944444444445in"
height="4.970138888888889in"}

> **Figure 4.5.4**. Fall Chinook Salmon Spawning Areas in Hanford Reach
> Area of the Columbia River, Washington

estimates steelhead sport catch for the 2002 season at 1100 fish. The
majority of these fish were marked hatchery fish. In recent years the
return of fall Chinook salmon has been high with 7550 adults and about
1000 jacks (precocious males) harvested during 2002
(<http://wdfw.wa.gov/fish/harvest/harvest.htm> ).

American shad (*Alosa sapidissima)*, an introduced anadromous species,
may also spawn in the Hanford Reach. The upstream range of the shad has
been increasing since 1956 when less than 10 adult shad passed McNary
Dam. Since then, the number of shad ascending Priest Rapids Dam has
risen to many thousands each year, and young-of-the-year have been
collected in the Hanford Reach. Shad are not dependent on the same
conditions that are required by salmonids for spawning and apparently
have found favorable conditions for reproduction.

Other fish of importance to sport fishermen are the native mountain
whitefish (*Prosopium williamsoni)* and white sturgeon (*Acipenser
transmontanus)*. Introduced species like smallmouth bass (*Micropterus
dolomieui)*, crappie (*Pomoxis nigromaculatus*), catfish (*Ictalurus
punctatus)*, walleye (*Stizostedion vitreum)*, and yellow perch (*Perca
flavescens)* are also popular. Large populations of rough fish are also
present, including introduced carp (*Cyprinus carpio)* and native
species such as redside shiner (*Richardsonius balteatus)*, suckers
(*Catostomus macrocheilus)*, and northern pikeminnow (*Ptychocheilus
oregonensis)*. Because northern pikeminnow feed on juvenile salmon, WDFW
has established a bounty program on adult pikeminnow to bolster salmon
runs. Northern pikeminnow removed from the Hanford Reach are usually
turned in at bounty stations located at Columbia Point in Richland and
at the Vernita Bridge rest stop.

#### Spring Streams

Small interrupted streams, such as Rattlesnake, Bobcat, and Snively
springs located on the Fitzner-Eberhardt Arid Lands Ecology Reserve
Unit, contain diverse biotic communities and are extremely productive
(Cushing and Wolf 1984). Dense blooms of watercress arise and are lost
when flash floods occur. Aquatic insect production is fairly high as
compared with mountain streams (Gaines 1987). The macrobenthic biota
varies from site to site and is related to the proximity of colonizing
insects and other factors. The fire of 2000 has had little direct impact
on the stream ecology, even though the riparian transect along the lower
two-thirds of the stream was heavily damaged by the fire (BAER 2000).

Rattlesnake Springs, on the western side of the Hanford Site, forms a
small surface stream that flows for about 2.5 km (1.6 mi) before
disappearing into the ground as a result of seepage and
evapotranspiration. Base flow of this stream is about 0.01 m^3^/s
(0.4 ft^3^/s) (Cushing and Wolf 1982). Water temperature ranges from 2°
to 22°C (36° to 72°F). Mean annual total alkalinity (as CaCO~3~),
nitrate nitrogen, phosphate phosphorus, and total dissolved solids are
127, 0.3, 0.18, and 217 mg/L, respectively (Cushing and Wolf 1982,
Cushing et al. 1980). The sodium content of the spring water is about
7 ppm (Brown 1970). Rattlesnake Springs is of ecological importance
because it provides a source of water to terrestrial animals in an
otherwise arid part of the Hanford Site. Snively Springs, located west
of and at a higher elevation than Rattlesnake Springs, is another source
of drinking water for terrestrial animals. Both springs provide a
valuable source of drinking water for the Rattlesnake Hills elk herd.
The major rooted aquatic plant, which in places may cover the entire
width of the stream, is watercress. Isolated patches of bulrush, spike
rush, and cattail occupy less than 5 percent of the streambed.

Primary productivity at Rattlesnake Springs is greatest during the
spring and coincident with the maximum periphyton standing crop. Net
primary productivity averaged 0.9 g/cm^2^/d organic matter during 1969
and 1970; the spring maximum was 2.2 g/cm^2^/d. Seasonal productivity
and respiration rates are within the ranges reported for arid region
streams. Although Rattlesnake Springs is a net exporter of organic
matter during much of the growing season, it is subject to flash floods
and severe scouring and denuding of the streambed during winter and
early spring, making it an importer of organic materials on an annual
basis (Cushing and Wolf 1984).

Secondary production is dominated by detritus-feeding collector-gatherer
insects (mostly Chironomidae and Simuliidae) that have multiple cohorts
and short generation times (Gaines et al. 1992). Overall production is
not high and is likely related to the low diversity found in these
systems related to the winter spates that scour the spring streams.
Total secondary production in Rattlesnake and Snively springs is 16,356
and 14,154 g dry weight/m^2^/yr, respectively. There is an indication
that insects in these spring-streams depend on both autochthonous
(originating within the stream) and allochthonous (originating outside
the stream) primary production as an energy source, despite significant
shading by non-native species of trees and shrubs (Mize 1993).

Invertebrate surveys on the Fitzner-Eberhardt Arid Lands Ecology Reserve
Unit identified 30 new taxa at Rattlesnake Springs and 12 new taxa at
Snively Springs (Soll et al. 1999). These recent findings bring the
total number of taxa at each spring to 43 and 24, respectively.

There are other springs occurring on the Rattlesnake Hills (Schwab et
al. 1979). Limited physical and chemical data are reported for each
site.

#### Temporary Water Bodies

West Lake is a small saline pond created by a rise in the water table in
the 200 Areas and is not fed by surface flow. Evaporation of groundwater
and possible disposal of sewage during the early Hanford years created
highly saline and alkaline conditions that greatly restricted the
complement of biota in West Lake (Poston et al. 1991).

Several artificial water bodies, both ponds and ditches, were formed as
a result of wastewater disposal practices associated with operation of
the reactors and separation facilities. Most of these have been taken
out of service and have been backfilled with the cessation of
activities. When present, however, they formed established aquatic
ecosystems complete with representative flora and fauna (Emery and
McShane 1980). The temporary wastewater ponds and ditches existed for as
long as two decades and covered fairly large areas. Rickard et al.
(1981) discusses the ecology of Gable Mountain Pond, one of the former
major lentic sites at Hanford. Emery and McShane (1980) present
ecological characteristics of all the temporary water bodies. The ponds
developed luxuriant riparian communities and became quite attractive to
autumn and spring migrating birds. Several species have nested near the
ponds. Section 4.4.1.8 describes those water bodies still active. These
former sites have been decommissioned and are now covered with
overburden and planted with grasses for stabilization.

### Threatened and Endangered Species

There are a number of species of plants and animals on the Hanford Site
that are considered to be rare and of management concern. Species listed
as endangered or threatened by either the federal government under the
Endangered Species Act (ESA) (50 CFR 17) or by the State of Washington
(WNHP 2005, WDFW 2005) are listed in Table 4.5.1. There are no federal-
or state-listed endangered or threatened mammals, reptiles, amphibians,
or invertebrates on the Hanford Site, but there are three species of
fish, five species of birds, and 11 species of plants listed as
threatened or endangered by either the state or federal governments.

Of the three listed fish species, only the upper Columbia River
steelhead trout (*Oncorhynchus mykiss*) spawns in the Hanford Reach,
although the extent of spawning is not known. Upper Columbia River
spring Chinook salmon (*O. tshawytscha*) do not spawn in the Hanford
Reach, but adults pass through the Hanford Reach while migrating to
spawning grounds, and the juveniles use the Hanford Reach as a nursery
area while they migrate toward the ocean. The bull trout (*Salvelinus
confluentus*) primarily inhabits smaller streams, usually at higher
elevations. Bull trout have been observed in the Hanford Reach on very
rare occasions, usually associated with the spring freshets. Bull trout
are not considered to be residents of the Hanford Site.

The bald eagle (*Haliaeetus leucocephalus*) is a relatively common
winter resident along the Hanford Reach that occasionally attempts to
nest on the Hanford Site. However, bald eagles have never successfully
nested on the Hanford Site. Bald eagle roosting and nesting sites are
protected from site employees by access controls that are in place from
November to March of each year.

Ferruginous hawks (*Buteo regalis*) have successfully nested on site,
especially on several steel transmission line towers. The white pelican
(*Pelecanus erythrorhynchos*) is relatively common along the Hanford
Reach but does not appear to nest or reproduce on site. The sandhill
crane (*Grus canadensis*) migrates over the site, and on rare occasions
is observed on the shore or islands of the Hanford Reach. The greater
sage grouse (*Centrocercus urophasianus*) was formerly more common on
the Hanford Site, especially on the Fitzner-Eberhardt Arid Lands Ecology
(ALE) Reserve Unit. It disappeared for a number of years following
several large fires in the 1980s. Since the late 1990s, there have been

**Table 4.5.1**. Federal or Washington State Threatened and Endangered
Species on the Hanford Site

+-------------------+------------------------+-----------+-----------+
| **Common Name**   | **Scientific Name**    | **Feder   | **Sta     |
|                   |                        | al^(a)^** | te^(a)^** |
+-------------------+------------------------+-----------+-----------+
| **Fish^(b)^**     |                        |           |           |
+-------------------+------------------------+-----------+-----------+
| Bull trout        | *Salvelinus            | T         | Candidate |
|                   | confluentus*           | hreatened |           |
+-------------------+------------------------+-----------+-----------+
| Spring-run        | *Oncorhynchus          | E         | Candidate |
| Chinook           | tshawytscha*           | ndangered |           |
+-------------------+------------------------+-----------+-----------+
| Steelhead         | *Oncorhynchus mykiss*  | E         | Candidate |
|                   |                        | ndangered |           |
+-------------------+------------------------+-----------+-----------+
| **Birds^(b)^**    |                        |           |           |
+-------------------+------------------------+-----------+-----------+
| American white    | *Pelecanus             |           | E         |
| pelican           | erythrorhynchos*       |           | ndangered |
+-------------------+------------------------+-----------+-----------+
| Bald eagle ^(c)^  | *Haliaeetus            | T         | T         |
|                   | leucocephalus*         | hreatened | hreatened |
+-------------------+------------------------+-----------+-----------+
| Ferruginous hawk  | *Buteo regalis*        | Species   | T         |
|                   |                        | of        | hreatened |
|                   |                        | Concern   |           |
+-------------------+------------------------+-----------+-----------+
| Sandhill crane    | *Grus canadensis*      |           | E         |
|                   |                        |           | ndangered |
+-------------------+------------------------+-----------+-----------+
| Greater sage      | *Centrocercus          | Candidate | T         |
| grouse            | urophasianus*          |           | hreatened |
+-------------------+------------------------+-----------+-----------+
| **Plants^(d)^**   |                        |           |           |
+-------------------+------------------------+-----------+-----------+
| Awned halfchaff   | *Lipocarpha (=         |           | T         |
| sedge             | Hemicarpha)            |           | hreatened |
|                   | aristulata*            |           |           |
+-------------------+------------------------+-----------+-----------+
| Desert dodder     | *Cuscuta denticulata*  |           | T         |
|                   |                        |           | hreatened |
+-------------------+------------------------+-----------+-----------+
| Geyer's milkvetch | *Astragalus geyeri*    |           | T         |
|                   |                        |           | hreatened |
+-------------------+------------------------+-----------+-----------+
| Grand redstem     | *Ammannia robusta*     |           | T         |
|                   |                        |           | hreatened |
+-------------------+------------------------+-----------+-----------+
| Loeflingia        | *Loeflingia squarrosa  |           | T         |
|                   | var. squarrosa*        |           | hreatened |
+-------------------+------------------------+-----------+-----------+
| Lowland toothcup  | *Rotala ramosior*      |           | T         |
|                   |                        |           | hreatened |
+-------------------+------------------------+-----------+-----------+
| Persistentsepal   | *Rorippa columbiae*    | Species   | E         |
| yellowcress       |                        | of        | ndangered |
|                   |                        | Concern   |           |
+-------------------+------------------------+-----------+-----------+
| Rosy pussypaws    | *Calyptridium roseum*  |           | T         |
|                   |                        |           | hreatened |
+-------------------+------------------------+-----------+-----------+
| Umtanum desert    | *Eriogonum codium*     | Candidate | E         |
| buckwheat         |                        |           | ndangered |
+-------------------+------------------------+-----------+-----------+
| White Bluffs      | *Lesquerella           | Candidate | T         |
| bladderpod        | tuplashensis*          |           | hreatened |
+-------------------+------------------------+-----------+-----------+
| White eatonella   | *Eatonella nivea*      |           | T         |
|                   |                        |           | hreatened |
+-------------------+------------------------+-----------+-----------+
| \(a\) Endangered  |                        |           |           |
| = species in      |                        |           |           |
| danger of         |                        |           |           |
| extinction within |                        |           |           |
| all or a          |                        |           |           |
| significant       |                        |           |           |
| portion of its    |                        |           |           |
| range.            |                        |           |           |
|                   |                        |           |           |
| > Threatened =    |                        |           |           |
| > species likely  |                        |           |           |
| > to become       |                        |           |           |
| > endangered in   |                        |           |           |
| > the foreseeable |                        |           |           |
| > future.         |                        |           |           |
| >                 |                        |           |           |
| > Candidate =     |                        |           |           |
| > species         |                        |           |           |
| > believed to     |                        |           |           |
| > qualify for     |                        |           |           |
| > threatened or   |                        |           |           |
| > endangered      |                        |           |           |
| > species status, |                        |           |           |
| > but for which   |                        |           |           |
| > listing         |                        |           |           |
| > proposals have  |                        |           |           |
| > not been        |                        |           |           |
| > prepared.       |                        |           |           |
| >                 |                        |           |           |
| > Species of      |                        |           |           |
| > concern =       |                        |           |           |
| > species not     |                        |           |           |
| > currently       |                        |           |           |
| > listed or       |                        |           |           |
| > candidates      |                        |           |           |
| > under the ESA,  |                        |           |           |
| > but are of      |                        |           |           |
| > conservation    |                        |           |           |
| > concern within  |                        |           |           |
| > specific USFWS  |                        |           |           |
| > regions.        |                        |           |           |
|                   |                        |           |           |
| \(b\)             |                        |           |           |
| <http://          |                        |           |           |
| www.dnr.wa.gov/nh |                        |           |           |
| p/refdesk/lists/a |                        |           |           |
| nimal_ranks.html> |                        |           |           |
| .                 |                        |           |           |
|                   |                        |           |           |
| \(c\) Currently   |                        |           |           |
| under review for  |                        |           |           |
| removal from the  |                        |           |           |
| list of           |                        |           |           |
| threatened or     |                        |           |           |
| endangered        |                        |           |           |
| species.          |                        |           |           |
|                   |                        |           |           |
| \(d\)             |                        |           |           |
| <htt              |                        |           |           |
| p://www.dnr.wa.go |                        |           |           |
| v/nhp/refdesk/lis |                        |           |           |
| ts/plantrnk.html> |                        |           |           |
| .                 |                        |           |           |
+-------------------+------------------------+-----------+-----------+

scattered sightings of greater sage grouse on ALE, and during 2003 a
dead sage grouse was found near the 100-F Area.

There are no plant species on the Hanford Site that are currently listed
as threatened or endangered under the ESA, but two species of plants are
candidates for federal protection: Umtanum desert buckwheat (*Eriogonum
codium*) which occurs in several small, highly localized populations on
Umtanum Ridge, and the White Bluffs bladderpod (*Lesquerella
tuplashensis*) which occurs on the White Bluffs. Several additional
plant species are listed as threatened or endangered by Washington
State. Several of these, including the awned halfchaff sedge
(*Lipocarpha aristulata*), grand redstem (*Ammannia robusta*), lowland
toothcup (*Rotala ramosior*), and persistentsepal yellowcress (*Rorippa
columbiae*) are restricted to wetlands in the riparian zone of the
Columbia River. Other plant species, such as loeflingia (*Loeflingia
squarrosa*) and rosy pussypaws (*Calypdridium roseum*), are small
annuals that have been found in relatively undisturbed sagebrush areas
in the vicinity of Gable Mountain. The remaining three state threatened
or endangered plant species (Geyer's milkvetch \[*Astragalus geyeri*\],
white eatonella \[*Eatonella nivea*\], and desert dodder \[*Cuscuta
denticulata*\]) have been found at various sites on the Wahluke slope.

In addition to the species listed by the state or federal resource
agencies as threatened or endangered, there are numerous species listed
by the State of Washington as candidate or sensitive animal species
(Table 4.5-2) or as sensitive, review, or watch list plants (Table
4.5-3). The common loon (*Gavia immer*) and the peregrine falcon (*Falco
peregrinus*) are the only animal species on the Hanford Site listed as
sensitive by Washington State; there are 17 species of plants listed as
state sensitive species.

The Washington ground squirrel (*Spermophilus washingtoni*), listed as a
candidate species by both the state and federal governments, is most
likely to occur in the Franklin or Grant county portions of the Hanford
Site. The Townsend's ground squirrel (*S. townsendii*), a Washington
State candidate species, may be found on the Benton County portions of
the Hanford Site.

Several state candidate and sensitive species, including the loggerhead
shrike (*Lanius ludovicianus*), burrowing owl (*Athene cunicularia*),
sagebrush lizard (*Sceloporus graciosus*), peregrine falcon,
goshawk (*Accipiter gentilis*), Columbia River spire snail (*Fluminicola
columbiana*), and California floater (*Anodonta californiensis*), as
well as the state threatened ferruginous hawk are considered to be
animal species of concern by the U.S. Fish and Wildlife Service (USFWS).
Three state sensitive plant species, Columbia milkvetch (*Astragalus
columbianus*), Hoover's desert parsley (*Lomatium tuberosum*), and gray
cryptantha (*Cryptantha leucophaea*), as well as the state endangered
persistentsepal yellowcress, are considered by USFWS to be species of
concern in the mid-Columbia Basin. Species of concern are not protected
under federal law, but are considered to be vulnerable and of special
management concern. More information about the plant species listed in
Table 4.5-3 can be found in Sackschewsky and Downs (2001).

A species of springsnail was discovered in the lower Hanford Reach
during 2004 that, depending on the taxonomic system used, is either the
Columbia springsnail (a species of *Pyrgulopsis* that has not been
formally described or named) or the Jackson Lake springsnail
(*Pyrgulopsis robusta*). Regardless of the name, the USFWS is currently
evaluating this species for possible listing as endangered or threatened
(70 FR 20512). This species currently has no federal or state status.

The USFWS has indicated that four additional federally listed
threatened, endangered, or candidate species may be present in Benton,
Franklin, or Grant counties (USFWS 2004). The pygmy rabbit (*Brachylagus
idahoensis*) is a federal and state endangered species that is
restricted to a few small populations north of the Hanford Site in Grant
and Adams counties. Biologists have searched for this species on the
Hanford Site, but it has not been conclusively observed. Ute Ladies
tresses (*Spiranthes diluvialis*) is a threatened orchid that
potentially could be found along the Columbia River but has not been
observed near the Site; it is documented in Chelan and Okanogan counties
(WNHP 2005). The yellow-billed cuckoo (*Coccyzus americanus*) is a
federal candidate species that has been rarely observed in southeast
Washington. It normally requires relatively large forested wetland areas
for successful breeding. Such habitat is not available on the Hanford
Site, and the species has not been observed on the Hanford Site. The
northern wormwood (*Artemisia campestris* var *wormskioldii*) is a
federal candidate and state endangered species that occurs along the
Columbia River near Wanapum Dam. Extensive surveys along the shore of
the Hanford Reach have failed to locate this species on the Hanford
Site. The USFWS (2004) also lists a number of additional species of
concern for Benton, Franklin, and Grant Counties, including a number of
bat species that may occur on the Hanford Site; most of these have no
Washington State-level status designation.

**Table 4.5-2. Washington State Candidate and Sensitive Animal Species
on the Hanford Site**

+--------------------------------------+-------------------------------+
| **Common Name**                      | **Scientific Name**           |
+--------------------------------------+-------------------------------+
| **Molluscs**                         |                               |
+--------------------------------------+-------------------------------+
| California floater^(a)^              | *Anodonta californiensis*     |
+--------------------------------------+-------------------------------+
| Giant Columbia River limpet          | *Fisherola* (= *Lanx*)        |
|                                      | *nuttalli*                    |
+--------------------------------------+-------------------------------+
| Giant Columbia River spire           | *Fluminicola (=               |
| snail^(a)^                           | Lithoglyphus*) *columbiana*   |
+--------------------------------------+-------------------------------+
| **Fish**                             |                               |
+--------------------------------------+-------------------------------+
| Bull trout^(b,c)^                    | *Salvelinus confluentus*      |
+--------------------------------------+-------------------------------+
| Mountain sucker^(c)^                 | *Catastomus platyrhynchus*    |
+--------------------------------------+-------------------------------+
| Leopard dace^(c)^                    | *Rhinichthys flacatus*        |
+--------------------------------------+-------------------------------+
| River Lamprey^(c)^                   | *Lampetra ayresi*             |
+--------------------------------------+-------------------------------+
| Spring-run Chinook salmon^(d)^       | *Oncorhynchus tshawytscha*    |
+--------------------------------------+-------------------------------+
| Steelhead^(d)^                       | *Oncorhynchus mykiss*         |
+--------------------------------------+-------------------------------+
| **Insects**                          |                               |
+--------------------------------------+-------------------------------+
| Columbia River tiger beetle^(e)^     | *Cicindela columbica*         |
+--------------------------------------+-------------------------------+
| **Birds**                            |                               |
+--------------------------------------+-------------------------------+
| Burrowing owl^(a)^                   | *Athene cunicularia*          |
+--------------------------------------+-------------------------------+
| Common loon^(f)^                     | *Gavia immer*                 |
+--------------------------------------+-------------------------------+
| Flamulated owl^(c)^                  | *Otus flammeolus*             |
+--------------------------------------+-------------------------------+
| Golden eagle                         | *Aquila chrysaetos*           |
+--------------------------------------+-------------------------------+
| Lewis's woodpecker^(c)^              | *Melanerpes lewis*            |
+--------------------------------------+-------------------------------+
| Loggerhead shrike^(a)^               | *Lanius ludovicianus*         |
+--------------------------------------+-------------------------------+
| Peregrine falcon^(a,f)^              | *Falco peregrinus*            |
+--------------------------------------+-------------------------------+
| Merlin                               | *Falco columbarius*           |
+--------------------------------------+-------------------------------+
| Northern goshawk^(a,c)^              | *Accipter gentilis*           |
+--------------------------------------+-------------------------------+
| Sage sparrow                         | *Amphispiza belli*            |
+--------------------------------------+-------------------------------+
| Sage thrasher                        | *Oreoscoptes montanus*        |
+--------------------------------------+-------------------------------+
| Western grebe                        | *Aechmorus occidentalis*      |
+--------------------------------------+-------------------------------+
| **Reptiles**                         |                               |
+--------------------------------------+-------------------------------+
| Sagebrush lizard^(a)^                | *Sceloporus graciosus*        |
+--------------------------------------+-------------------------------+
| Striped whipsnake                    | *Masticophis taeniatus*       |
+--------------------------------------+-------------------------------+
| **Mammals**                          |                               |
+--------------------------------------+-------------------------------+
| Black-tailed jackrabbit              | *Lepus californicus*          |
+--------------------------------------+-------------------------------+
| Merriam's shrew                      | *Sorex merriami*              |
+--------------------------------------+-------------------------------+
| Townsend's ground squirrel           | *Spermophilus townsendii*     |
+--------------------------------------+-------------------------------+
| Washington ground squirrel^(c,g)^    | *Spermophilus washingtoni*    |
+--------------------------------------+-------------------------------+
| White-tailed jackrabbit              | *Lepus townsendii*            |
+--------------------------------------+-------------------------------+
| \(a\) Federal species of concern.    | \(f\) State Sensitive (i.e.,  |
|                                      | taxa vulnerable or declining) |
| \(b\) Federal threatened.            | and could become endangered   |
|                                      | or threatened without active  |
| \(c\) Reported, but seldom observed, | management or removal of      |
| on the Hanford Site.                 | threats..                     |
|                                      |                               |
| > \(d\) Federal endangered           | \(g\) Federal candidate       |
| >                                    |                               |
| > \(e\) Probable, but not observed,  |                               |
| > on the Hanford Site.               |                               |
+--------------------------------------+-------------------------------+

**Table 4.5-3**. Washington State Plant Species of Concern on the
Hanford Site

+-------------------------+-----------------------------+-------------+
| **Common Name**         | **Scientific Name**         | **State     |
|                         |                             | Lis         |
|                         |                             | ting**^(a)^ |
+=========================+=============================+=============+
| Annual paintbrush       | *Castilleja exilis*         | Watch List  |
+-------------------------+-----------------------------+-------------+
| Annual sandwort         | *Minuartia pusilla var.     | Review      |
|                         | pusilla*                    | Group 1     |
+-------------------------+-----------------------------+-------------+
| Basalt milk-vetch       | *Astragalus conjunctus var. | Watch List  |
|                         | rickardii*                  |             |
+-------------------------+-----------------------------+-------------+
| Beaked spike-rush       | *Eleocharis rostellata*     | Sensitive   |
+-------------------------+-----------------------------+-------------+
| Bristly combseed        | *Pectocarya setosa*         | Watch List  |
+-------------------------+-----------------------------+-------------+
| Brittle prickly pear    | *Opuntia fragilis*          | Review      |
|                         |                             | Group 1     |
+-------------------------+-----------------------------+-------------+
| Canadian St. John's     | *Hypericum majus*           | Sensitive   |
| wort                    |                             |             |
+-------------------------+-----------------------------+-------------+
| Chaffweed               | *Centunculus minimus*       | Review      |
|                         |                             | Group 1     |
+-------------------------+-----------------------------+-------------+
| Columbia milkvetch      | *Astragalus columbianus*    | Sensitive   |
|                         |                             | ^(b)^       |
+-------------------------+-----------------------------+-------------+
| Columbia River mugwort  | *Artemisia lindleyana*      | Watch List  |
+-------------------------+-----------------------------+-------------+
| Coyote tobacco          | *Nicotiana attenuata*       | Sensitive   |
+-------------------------+-----------------------------+-------------+
| Crouching milkvetch     | *Astragalus succumbens*     | Watch List  |
+-------------------------+-----------------------------+-------------+
| Desert evening-primrose | *Oenothera caespitosa*      | Sensitive   |
+-------------------------+-----------------------------+-------------+
| Dwarf evening primrose  | *Camissonia (= Oenothera)   | Sensitive   |
|                         | pygmaea*                    |             |
+-------------------------+-----------------------------+-------------+
| False pimpernel         | *Lindernia dubia            | Watch List  |
|                         | anagallidea*                |             |
+-------------------------+-----------------------------+-------------+
| Fuzzytongue penstemon   | *Penstemon eriantherus      | Sensitive   |
|                         | whitedii*                   |             |
+-------------------------+-----------------------------+-------------+
| Giant helleborine       | *Epipactis gigantea*        | Watch List  |
+-------------------------+-----------------------------+-------------+
| Gray cryptantha         | *Cryptantha leucophaea*     | Sensitive   |
|                         |                             | ^(b)^       |
+-------------------------+-----------------------------+-------------+
| Great Basin gilia       | *Gilia leptomeria*          | Sensitive   |
+-------------------------+-----------------------------+-------------+
| Hedge hog cactus        | *Pediocactus simpsonii var. | Review      |
|                         | robustior*                  | Group 1     |
+-------------------------+-----------------------------+-------------+
| Hoover's desert parsley | *Lomatium tuberosum*        | Sensitive   |
|                         |                             | ^(b)^       |
+-------------------------+-----------------------------+-------------+
| Kittitas larkspur       | *Delphinium multiplex*      | Watch List  |
+-------------------------+-----------------------------+-------------+
| Medic milkvetch         | *Astragalus speirocarpus*   | Watch List  |
+-------------------------+-----------------------------+-------------+
| Miner's candle          | *Cryptantha scoparia*       | Sensitive   |
+-------------------------+-----------------------------+-------------+
| Mousetail               | *Myosurus clavicaulis*      | Sensitive   |
+-------------------------+-----------------------------+-------------+
| Piper's daisy           | *Erigeron piperianus*       | Sensitive   |
+-------------------------+-----------------------------+-------------+
| Porcupine sedge         | *Carex hystericina*         | Watch List  |
+-------------------------+-----------------------------+-------------+
| Robinson's onion        | *Allium robinsonii*         | Watch List  |
+-------------------------+-----------------------------+-------------+
| Rosy balsamroot         | *Balsamorhiza rosea*        | Watch List  |
+-------------------------+-----------------------------+-------------+
| Scilla onion            | *Allium scilloides*         | Watch List  |
+-------------------------+-----------------------------+-------------+
| Shining flatsedge       | *Cyperus bipartitus         | Sensitive   |
|                         | (rivularis)*                |             |
+-------------------------+-----------------------------+-------------+
| Small-flowered          | *Camissonia (= Oenothera)   | Sensitive   |
| evening-primrose        | minor*                      |             |
+-------------------------+-----------------------------+-------------+
| Small-flowered nama     | *Nama densum var.           | Watch List  |
|                         | parviflorum*                |             |
+-------------------------+-----------------------------+-------------+
| Smooth cliffbrake       | *Pellaea glabella simplex*  | Watch List  |
+-------------------------+-----------------------------+-------------+
| Snake River cryptantha  | *Cryptantha spiculifera (=  | Sensitive   |
|                         | C. interrupta)*             |             |
+-------------------------+-----------------------------+-------------+
| Southern mudwort        | *Limosella acaulis*         | Watch List  |
+-------------------------+-----------------------------+-------------+
| Stalked‑pod milkvetch   | *Astragalus sclerocarpus*   | Watch List  |
+-------------------------+-----------------------------+-------------+
| Suksdorf's monkey       | *Mimulus suksdorfii*        | Sensitive   |
| flower                  |                             |             |
+-------------------------+-----------------------------+-------------+
| Thompson's sandwort     | *Arenaria franklinii        | Review      |
|                         | thompsonii*                 | Group 2     |
+-------------------------+-----------------------------+-------------+
| Winged combseed         | *Pectocarya penicillata*    | Watch List  |
+-------------------------+-----------------------------+-------------+
| \(a\) Sensitive - Taxa  |                             |             |
| that are vulnerable or  |                             |             |
| declining and could     |                             |             |
| become endangered or    |                             |             |
| threatened without      |                             |             |
| active management or    |                             |             |
| removal of threats.     |                             |             |
|                         |                             |             |
| Review Group 1 - Taxa   |                             |             |
| for which currently     |                             |             |
| there are insufficient  |                             |             |
| data available to       |                             |             |
| support listing as      |                             |             |
| threatened, endangered, |                             |             |
| or sensitive, and the   |                             |             |
| State is actively       |                             |             |
| searching for           |                             |             |
| additional data or      |                             |             |
| information.            |                             |             |
|                         |                             |             |
| Review Group2 - Taxa    |                             |             |
| with unresolved         |                             |             |
| taxonomic questions     |                             |             |
| that would affect the   |                             |             |
| listing status.         |                             |             |
|                         |                             |             |
| Watch List - Taxa that  |                             |             |
| are more abundant       |                             |             |
| and/or less threatened  |                             |             |
| than previously         |                             |             |
| assumed, but still of   |                             |             |
| interest to the State.  |                             |             |
|                         |                             |             |
| \(b\) USFWS Columbia    |                             |             |
| Basin federal species   |                             |             |
| of concern.             |                             |             |
+-------------------------+-----------------------------+-------------+

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##  {#section .unnumbered}

[^1]: (?) Management of these islands is the responsibility of the
    island owners, which include DOE, USFWS, and the U.S. Bureau of Land
    Management. Island ownership descriptions pertain to status prior to
    national monument designation and are subject to change with
    agreements among the agencies.

[^2]: (?) Source: Personal communication between T. M. Poston and L.L.
    Cadwell, PNNL, April 2002.