I have 3 Pekin and 3 Khakis of which I have an idea but am not totally sure of sex. I also have three Mallards - 2 already have green heads just waiting on the third to get older so I can tell. I'm afraid I have 1 male Khaki and 2 male Pekin....I'll attach photos of the Pekin tails and photos of the Khakis. The khaki tails aren't showing and curls/lack thereof. I tried to tell from bill/bean color on the Khakis but I'm not sure that's reliable.... Anyway, here they are. male I think? male I think? definitely female judging by her quack... Just the Pekin for now, I'll get photos of the Khakis when I put them to bed.