As Gombei was getting his duck by the marsh in Japan he noticed how sad and cruel it was to catch more than 1 duck so he promised to never ever catch more than 1 duck per day.
On one cold morning when he woke up he felt a ache/pain in his bones from going out everyday to catch a duck. He had a plan to catch tons of ducks in one day so he wouldnt have to go out everyday.
He turned back into a human and promised to never catch a duck ever again and grow food for the ducks to make up for what he did everyday. Theme:If you feel what other people are feeling when you are doing something bad imagine how you would feel if you were trapped.
As he was waiting for the 100 duck to get stuck in his trap he started to grow wings a bill, and feathers.
He had turned into a duck and was being trapped just like the other ducks were and felt bad.