According to Genesis, a dove first returned to Noah with a sign of dry land. Noah sent the dove from the Ark after first sending a raven. On its second return, the dove carried a freshly plucked olive leaf, showing that the floodwaters had receded.
Genesis 8 describes the sequence: Noah opens the window, sends out a raven, and later sends a dove to test whether the waters have diminished. The dove initially finds nowhere to land, then returns with the olive leaf, and finally does not return after being released again.
The olive branch or olive leaf became a widely recognized symbol of peace and renewal. The biblical passage itself specifically mentions an olive leaf, not an olive branch. The raven and dove are both part of the episode, but the dove is the bird associated with the clear sign of emerging vegetation.