L. L. Cadwell and M. A. Simmons
The Hanford Site is a relatively large, undisturbed area of shrub-steppe that contains numerous plant and
animal species adapted to the region's semiarid environment. The vegetation mosaic of the Site consists of
ten major plant communities: 1) sagebrush/bluebunch wheatgrass, 2) sagebrush/cheatgrass or
sagebrush/Sandberg's bluegrass, 3) sagebrush-bitterbrush/cheatgrass, 4) grease wood/cheatgrass-saltgrass, 5)
winterfat/Sandberg's bluegrass, 6) thyme buckwheat/Sandberg's bluegrass, 7) cheatgrass-tumble mustard, 8)
willow or riparian, 9) spiny hopsage, and 10) sand dunes (Cushing 1994). Nearly 600 species of plants have
been identified on the Hanford Site (Sackschewsky et al. 1992). Cheatgrass is the dominant plant on old
fields that were cultivated approximately 50 years ago.
More than 300 species of terrestrial and aquatic insects, 12 species of reptiles and amphibians, 44 species of
fish, 187 species of birds, and 39 species of mammals have been found on the Hanford Site (Cushing 1994).
Deer and elk are the major large mammals on the Site; coyotes are plentiful, and the Great Basin pocket
mouse is the most abundant mammal. Waterfowl are numerous on the Columbia River, and the bald eagle is
a regular winter visitor along the river. Salmon and steelhead are the fish species of most interest to sport
fishermen and Native American tribal members.
There are two types of natural aquatic habitats on the Hanford Site; one is the Columbia River, and the other
is provided by the small spring-streams and seeps located mainly on the ALE Reserve in the Rattlesnake
Hills. These include Rattlesnake Springs, Dry Creek, Snively Springs, and West Lake, a small, natural pond
near the 200 Areas. Several artificial water bodies, both ponds and ditches, have been formed as a result of
waste-water disposal practices associated with the operation of the reactors and separation facilities; these
water bodies form established aquatic ecosystems complete with representative flora and fauna (Emery and
McShane 1980).
The Hanford Site contains no plant species listed on the federal list of threatened and endangered species.
The federal government lists the peregrine falcon as endangered and the bald eagle and Aleutian Canada
goose as threatened. The peregrine falcon and Aleutian Canada goose are migrants through the Hanford Site,
and the bald eagle is a common winter resident. Several plant species, mammals, birds, molluscs, reptiles,
and invertebrates occurring on the Hanford Site are currently candidates for formal listing under the
Endangered Species Act. Appendix G lists special-status species that could occur on the Hanford Site.
Results for Wildlife Resource Monitoring, 1994
Wildlife populations inhabiting the Hanford Site are monitored to measure the status and condition of the
populations and assess effects of Hanford operations. Particular attention is paid to species that are rare,
threatened, or endangered nationally or statewide and those species that are of commercial, recreational, or
aesthetic importance statewide or locally. These species include the bald eagle, chinook salmon, Canada
goose, ferruginous hawk, Rocky Mountain elk, mule deer, loggerhead shrike, and other bird species.
Fluctuations in wildlife and plant species on the Hanford Site appear to be a result of natural ecological
factors and management of the Columbia River system. The establishment and management of the Hanford
Site has helped to maintain wildlife populations and overall biological diversity relative to probable
alternative uses of the Site.
Bald Eagle
The bald eagle is listed as a federally threatened species and also a Washington state threatened species.
Historically, bald eagles have wintered along the Hanford Reach of the Columbia River. However, when
monitoring began in the early 1960s, numbers were very low (Figure
4.2.1).
Following the passage of the Endangered Species Act in 1973, the number of wintering bald eagles increased.
Possible reasons for the observed increase are the added protection of bald eagles at nesting locations off the
Hanford Site and the nationwide elimination of dichlorodiphenyltrichloroethane (DDT) as an agricultural
pesticide in 1972. On a local scale, changes in the number of eagles on the Hanford Site generally correspond
to changes in the number of salmon, a major fall and winter food source for eagles. The recent decline in
numbers is probably attributable to the recent decline in salmon in the area. Most of the eagles using the
Hanford Reach are concentrated in the section between the old Hanford Townsite and the 100-K Area.
The Hanford Reach is expected to continue providing wintering habitat as long as critical resources such as
food, perches, and relative freedom from human activities are maintained. Limited nest building by bald
eagles has been observed at the Hanford Site in recent years although none of the attempts has been
successful.
Chinook Salmon
Chinook salmon are an important resource to the citizens of the Pacific Northwest. Salmon are caught
commercially and for recreation. The commercial and recreational catch is carefully managed to sustain the
resource. Today the most important natural spawning area in the mainstream Columbia River for the fall
chinook salmon is found in the free-flowing Hanford Reach. In the early years of the Hanford Site, there
were few spawning nests (redds) in the Hanford Reach (Figure
4.2.2).
Between 1943 and 1971, a number of dams were constructed on the Columbia River. The reservoirs created
behind the dams eliminated most mainstem spawning areas and increased salmon spawning in the Hanford
Reach. Fisheries management strategies aimed at maintaining spawning populations in the mainstem
Columbia River have also contributed to the observed increases. In recent years, numbers of fall chinook
salmon spawning in the Hanford Reach have declined, consistent with reduced run sizes returning to the
Columbia River. The larger 1994 redd count was partly the result of harvest restrictions directed at protecting
Snake River stocks of fall chinook salmon under the Endangered Species Act. Also, for most of the surveys
conditions were excellent for observing the redds. Additionally, low daytime discharges from Priest Rapids
Dam contributed to generally low water as far downstream as Ringold. Redds were visible in the lower part
of the Reach for the first time in many years. The Hanford Reach under existing management practices
continues to provide valuable salmon spawning habitat.
Canada Goose
Nesting Canada geese are valuable recreational and aesthetic resources along the Snake and Columbia rivers
in eastern Washington. Goose nesting surveys began in the 1950s to monitor changes in response to reactor
operations (Figure
4.2.3).
The gradual decline observed in the late 1960s and early 1970s is attributed to persistent coyote predation,
mostly on the Columbia River islands upstream from the old Hanford Townsite. Since the 1970s, the center
of the nesting population has shifted from upstream to downstream islands near Richland, which in recent
years have been relatively free from coyote predation. The lower nest count in 1994 can be attributed to
extensive coyote predation on Island 12 (a downstream island). In 1993, there were 60 nests on Island 12
while no nests were found in 1994.
Canada goose populations are successful on the Hanford Reach because the islands are restricted from human
uses during the nesting period and because shoreline habitats provide adequate food and cover for broods
(Eberhardt et al. 1989).
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