A Duckling With Interspecies Compassion

Have you seen this short video of a baby duck feeding carp?

It's hard to see the duck at first because it blends in with the background. The duck is in the center of the frame, slightly toward the right. I had no idea that one species would feed another in a direct way (I mean other than being the food for a larger animal). Is this behavior unusual?

This baby duck has more intelligence and compassion than some humans.