In the banner photo above, a female spring Chinook salmon is digging a depression in the 2-4 inch gravel in the riverbed with her tail.  She will then deposit some of her eggs in this depression, move above it, & dig again covering the eggs in the first depression with the gravel she displaces.  She repeats this process 5 to 7 times until she has dug up an area measuring 20 feet long by 10 feet wide and over 1 foot deep.  In all, the gravel she displaces with her tail would fill a dump truck.  When finished 3,000-5,000 eggs will be buried in the gravel in the bottom of the riverbed.  The female will defend this nest area or redd for as long as her strength lasts against other females digging it up, and then she will die.