Genesis 8:8-11
8:8 Then Noah sent out a dove to see if the waters had receded from the surface of the ground.
8:9 The dove could not find a resting place for its feet because water still covered the surface of the entire earth, and so it returned to Noah in the ark. He stretched out his hand, took the dove, and brought it back into the ark.
8:10 He waited seven more days and then sent out the dove again from the ark.
8:11 When the dove returned to him in the evening, there was a freshly plucked olive leaf in its beak! Noah knew that the waters had receded from the earth.