I have a blue fawn call duck who has successfully hatched her own 6 eggs. She is in a separate enclosure with her ducklings and all is going well. They were hatched on June 19th. When can she be safely returned with her ducklings to her mate who has the freedom of our garden or alternatively when can the drake be put in with her and the ducklings? I have heard that Drakes can have a tendency to kill the ducklings.