What happend to the eggs?

I have a night aviary building covered in 2X2 wire with a 1/2 hardware cloth 4*" high also from ground up also a 2 ft. apron around it and a 4 ft . hotwired top and bottom fence around the aviary. I let my goose 1 yr old set on some duck eggs. She seemed very diligent and the other geese stayed close to her. She only got off the next a bit for a few min. a day. The geese are allowed to go in a fenced yard ajacent for grass. She started with 8 eggs or so, then there were only about 3 or 4, then she got up one day after a month and nothing. I had straw about a foot deep in the pen. Where did the eggs go? If they were bad, do they just explode and disintegrate or what ? Not a piece of egg left? Or did the geese eat them? They seemed protective of her and the nest. We do live in a rural area with trees and pastures. There are snakes, (Black Kingsnake, Rat snakes at neighbors crawlspace, even Copperheads & Timber Rattlesnakes --North Georgia) -- could a snake crawl in, and eat the eggs without the goose/geese doing anything? I did find a baby black king under the water pan in my mini-duck pen ,which is covered top to bottom and bottom in 1/2 hardware cloth and 2X2 wire. He must have been able to go thru the 1/2 wire. There also have been mice turds I some of my feeders, so I take food out at night, but mice could get in, and I leave the aviary doors open to the day yard in the daytime. The bottom is gravel and I haven't found any snake holes so they'd have to go thru the fences and the bottom is hotwired about 8" up.....