So this is my first year raising ducks. Originally we had two mallard ducklings which are about almost a month old. Unfortunately on Thursday we woke up to one of the ducklings dead We're not too sure what happened, but ever since the living duckling has been hissing at us and trying to bite us anytime we're near him/her. Does anyone have any advice? Is this normal? How can we make him/her feel more comfortable?