He compares this reaction to humans who tend to hang onto that negative energy by holding grudges and thinking/talking/obsessing about it. It becomes our story.
"We are a species that has lost its way. Everything natural, every flower or tree, and every animal have important lessons to teach us if we would only stop, look, and listen. Our duck’s lesson is this: Flap your wings—which translates as ‘let go of the story’—and return to the only place of power: the present moment"...Eckhart Tolle