I don't think they're eggs. In another picture from near-ground level, they seem to have a
flat top, not round-shaped, sort of like a canister containing something. It is just my impression and probably I'm very wrong.
Also, in the above picture, the 'eggs' don't have the same size. Maybe it's because of the bad quality.
EDIT:
Okay, so if you look carefully at the eggs in the foreground, they seem to have a flat top.
And for some reason, I think it has something to do with this:
It looks like someone is sticking his hand inside an 'egg' and slimy, green goo covers his arm.