The colony, which now nests five miles from the river mouth on East Sand Island from April to midsummer, gobbled up an estimated 4.2 million juvenile salmonids this year as the fish forged toward the Pacific Ocean, according to a draft 2003 summary report on the summer field season.
That compares to a peak of an estimated 12.4 million consumed by the terns in 1998, the second year of the study that has been financed by the Bonneville Power Administration.