Organized in 1966 by the Fish and Wildlife Service,the Breeding Bird Survey uses annual roadside counts along established routes for monitoring of population changes of as many as, or of more than 250 bird species, including 180 songbirds.
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Afor monitoring of population changes of as many as, or of
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Bto monitor population changes of as many, or
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Cto monitor changes in the populations of
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Dthat monitors population changes of
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Ethat monitors changes in populations of as many as,or
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