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The San Clemente Sage Sparrow (SCSS), a subspecies of the Sage Sparrow, is on the U.S. Endangered Species List. It is classified as threatened in California. This species lives only on San Clemente Island, in the Channel Islands.

Its numbers declined rapidly when feral goats and pigs, introduced to the island, destroyed vegetation that the bird lives in. The feral grazers have been removed and the island vegetation is slowly recovering. Since the late 1990s there have been conducted several SCSS surveys. The sparrow's numbers appear to have begun to climb slowly as a result of these recovery efforts. In addition to surveys, since 1999, the Institute has been conducting research on annual productivity and nest success, nest site characteristics, habitat characteristics, territory size and density, and juvenile and adult survival.

It seems that the SCSS numbers are increasing also because the birds have adapted to maritime desert scrub habitat, cactus, and salt-bush. The majority of breeding territories are found on the lower, flat terraces between 10 m and 30 m above sea level, although nesting sites have been found as high as 150m above sea level. Nests are typically placed low to the ground in a boxthorn shrub, using the surrounding vegetation as cover.

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Endangered and Threatened Wildlife and Plants

San Clemente Island Bell's Sparrow