Editing Willamette River (section)

==Flora and fauna==
[[File:Osprey mg 9605.jpg|right|upright|thumb|alt=Osprey|Osprey are among bird species often seen along the Willamette River.]]
Over the past 150 years, a significant change for the Willamette River has been the loss of its floodplain forests, which covered an estimated 89&nbsp;percent of a {{convert|400|ft|m|adj=on}} band along each river bank in 1850.<ref name="Benke 619"/> By 1990, only 37&nbsp;percent of this zone was forested; the rest had been converted to farm fields or cleared for urban or suburban uses.<ref name="Benke 619"/> The remaining forests close to the river include stands of [[Populus trichocarpa|black cottonwood]], [[Fraxinus latifolia|Oregon ash]], [[willow]], and [[Acer macrophyllum|bigleaf maple]].<ref name="Benke 619">Benke, ''et al.'', p. 619</ref> The central valley—a former perennial grass prairie interspersed with oak, [[Douglas fir]], [[Pinus ponderosa|ponderosa pine]], and other trees—is devoted almost entirely to farming. Douglas fir, [[Tsuga heterophylla|western hemlock]], and [[Thuja plicata|western red cedar]] dominate the forest on the Coast Range side of the basin. Forests to the east in the Cascade Range are predominantly Douglas fir, [[Abies amabilis|Pacific silver fir]], western hemlock, and western red cedar.<ref name="Benke 617" /><ref name="Benke 616"/>

Fish in the Willamette basin include 31 native species, among them [[Coastal cutthroat trout|cutthroat]], [[Bull trout|bull]], and [[rainbow trout]], several species of [[salmon]], [[Catostomidae|sucker]], [[minnow]], [[sculpin]], and [[lamprey]], as well as [[sturgeon]], [[stickleback]], and others. Among the 29 non-native species in the basin, there are [[Brook trout|brook]], [[Brown trout|brown]], and [[lake trout]], [[Largemouth bass|largemouth]] and [[Smallmouth bass|smallmouth]] bass, [[walleye]], [[carp]], [[bluegill]], and others. In addition to fish, the basin supports 18 species of amphibians, such as the [[Pacific giant salamander]]. [[Beaver]] and [[North American river otter|river otter]] are among 69 mammal species living in the watershed, also frequented by 154 bird species, such as the [[American dipper]], [[osprey]], and [[harlequin duck]]. [[Garter snake]]s are among the 15 species of reptiles found in the basin.<ref name="Benke 620-21"/>

Species diversity is greatest along the lower river and its tributaries. Threatened, endangered, or sensitive species include spring Chinook salmon, winter steelhead, [[chum salmon]], [[Coho salmon]] and [[Oregonichthys|Oregon chub]].<ref name="Benke 620-21">Benke, ''et al.'', pp. 620–21</ref> In the central valley, several projects have been done to restore and protect wetlands<ref>{{cite web |title=Willamette Valley Projects |url=http://www.ohjv.org/projects/willamette.html |publisher=Oregon Habitat Joint Venture |archive-url=https://web.archive.org/web/20160313132319/http://ohjv.org/projects/willamette.html |archive-date=March 13, 2016 |date=November 14, 2001 |url-status=dead}}</ref> in order to provide habitat for [[bald eagle]]s, [[Fender's blue butterfly]], Oregon chub, [[Lomatium bradshawii|Bradshaw's desert parsley]], a variety of [[Erigeron decumbens|Willamette fleabane]], and [[Lupinus sulphureus|Kincaid's lupine]].<ref>{{cite web |title=Threatened & Endangered Species |url=http://www.fws.gov/refuge/William_L_Finley/Wildlife_and_Habitat/T_E_Species.html |work=William L. Finley National Wildlife Refuge |publisher=U.S. Fish and Wildlife Service |archive-date=July 15, 2015 |archive-url=https://web.archive.org/web/20150715014856/http://www.fws.gov/refuge/William_L_Finley/Wildlife_and_Habitat/T_E_Species.html |url-status=dead}}</ref><ref>{{cite web |url=http://www.fws.gov/refuge/Baskett_Slough/wildlife_and_habitat/T_and_E.html |title=Threatened & Endangered Species |work=Baskett Slough National Wildlife Refuge |publisher=U.S. Fish and Wildlife Service |archive-date=July 15, 2015 |archive-url=https://web.archive.org/web/20150715021656/http://www.fws.gov/refuge/Baskett_Slough/wildlife_and_habitat/T_and_E.html |url-status=dead}}</ref><ref>{{cite news |last=Zaveri |first=Mihir |title=In Oregon's Willamette Valley, the Race to Save the Endangered Fender's Blue Butterfly |url=https://www.oregonlive.com/environment/2011/06/a_research_team_studies_the_en.html |newspaper=The Oregonian |date=June 17, 2011 |access-date=December 21, 2022}}</ref><ref name=federalregister>{{cite web |url=https://www.federalregister.gov/documents/2023/01/12/2023-00037/endangered-and-threatened-wildlife-and-plants-reclassifying-fenders-blue-butterfly-from-endangered |title=Endangered and Threatened Wildlife and Plants; Reclassifying Fender's Blue Butterfly From Endangered to Threatened With a Section 4(d) Rule |date=January 12, 2023 |author=U.S. Fish and Wildlife Service |work=Federal Register |publisher=National Archives |access-date=May 29, 2023}}</ref> In the early 21st&nbsp;century, osprey populations are increasing along the river, possibly because of a ban on the pesticide [[DDT]] and on the birds' ability to use power poles for nesting.<ref name="Benke 621">Benke, ''et al.'', p. 621</ref> Beaver populations, presumed to be much lower than historic levels, are increasing throughout the basin.<ref name="Benke 621"/>