What practical function did the breed's white coat serve during luring activities?

Answer

It provided camouflage against the bright sky when viewed from below by the ducks

The white coloring was not just aesthetic; it served the practical purpose of providing camouflage against the bright sky when viewed from the perspective of the ducks swimming below.

What practical function did the breed's white coat serve during luring activities?
animalDogusebreedKooikerhondje