ok my friendly neighborhood duck people. need help please. I have an large appleyard drake for 3 silver appleyard ducks. have been getting 2 eggs day for 3 weeks now. problem is only 5 out of 12 fertile that I'm incubating. set within week of laying. This week I placed my smaller appleyard drake and his mate with the rest of flock because I read larger drakes sometimes have low fertility. environment is open range farm, with lock up at night. buried 350 gallon water tank access in day and kiddy pool in pen with fresh water 5 gal jug with nipples for fresh water at night in barn. flock game bird feed mixed with chicken crumbles. any suggestions how to get fertility up.