Hiding females

[meredith5469]

I have 4 ducks- 2 drakes and 2 females (pekin-"bubbles" and mallard-"duck"). The mallard has nested before but the eggs never hatched due to very cold weather. For the past 3 or 4 days I have only seen "duck" once and bubbles only comes out in the evenings. We have a fenced in yard but I can't find them anywhere. I'm thinking overmating is the issue and the females are hiding, but I haven't seen "duck" in 2 days. Is it possible that she is nesting and bubbles is keeping her company? When she nested before she wouldn't let any of the ducks near her. It's possible a predator got her but I find it odd that bubbles is gone all day also and comes back covered in mud. I know we need to get more females. Working on that now. All of them are a year old.