Consumption rates and total mercury concentration of food items and consumers collected at six sites on the Colorado River in the Grand Canyon. Sites ranged from 0-367 river kilometers downstream of Lees Ferry (AZ, USA). Samples were analyzed for total Hg using cold vapor atomic fluorescence (CVAF, Tekran Model 2600 CVAF spectrometer) following EPA Method 7474. Consumption rate samples were collected quarterly from July 1, 2007 to June 30, 2009. Food items and consumers were collected June 12-28 2008.