With an ample supply of marine prey fish available, salmon consumption in the Columbia River estuary by the world’s largest Caspian tern colony last spring and summer dropped to an all-time low since research on the birds’ diet began in 1997.
With an ample supply of marine prey fish available, salmon consumption in the Columbia River estuary by the world’s largest Caspian tern colony last spring and summer dropped to an all-time low since research on the birds’ diet began in 1997.