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as the rivers, including the Sacramento and San Joaquin, drained the Sierra
Nevada and overtopped their natural levees. Large trees—sycamores, wil-
lows, cottonwoods, and oaks—once grew along these rivers in abundance.
h e Central Valley was also home to prolii c wildlife: grizzly bears, antelope,
Tule elk, salmon, and millions of migratory birds along the Pacii c Flyway
during the winter, including pelicans, geese, ducks, and cranes.
Although hunting, i shing, and other activities took a heavy toll on the
wildlife there throughout the late nineteenth and early twentieth centuries,
heavier impacts to wetlands began during the mid- to late nineteenth cen-
tury as settlers were encouraged to drain and reclaim these “unproductive”
wetlands. h e catastrophic 1861-62 l oods, and large l oods that followed,
prompted landowners in the Central Valley to begin small-scale land rec-
lamation and l ood control measures. But the greatest blow to wetlands of
the Central Valley resulted from the era of dam building in the twentieth
century, particularly the Central Valley Project in the late 1930s. h ese water
projects, including the building of levees along the Sacramento and San
Joaquin rivers and their tributaries, prevented winter and spring l oodwaters
from spreading out into their natural l oodplains, destroying wetlands, shal-
low lakes, and habitats for i sh and wildlife.
h e Central Valley once contained four to i ve million acres of wetlands;
by the late twentieth century, only 400,000 acres remained. As the wetlands
disappeared, so did the wildlife that depended on them, including the win-
tering waterfowl—from tens of millions in the 1940s to only about three-
and-a-half million by the end of the twentieth century.
Particularly heartbreaking was the fate of the three ancient lakes—Buena
Vista, Tulare, and Kern—in the southern end of the Central Valley. h ese
lakes, and the wetlands between them, formed the most extensive contiguous
region of wetland in California, covering an estimated 500,000 acres. Tulare
was at one time the largest freshwater lake west of the Great Lakes, with four
times the surface area of Lake Tahoe. Dating of sediments cored from the
Tulare Basin shows that the lake formed over a million years ago, making
it one of the oldest lakes in California. h ese three lakes and their wetlands
hosted an incredible diversity of wildlife, with thousands of wild horse, elk,
antelope, deer, grizzly and brown bear, wolf, coyote, ocelot, lion, wildcat,
beaver, and fox. Birds numbered in the millions, including ducks, swans,
marsh wrens, rails, and geese, using the lakes as a stopover point along the
Pacii c Flyway. Tulare Lake also hosted the southernmost run of chinook
salmon in the United States.
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