Could be my EE, June, but she was in the nest next to the one where I found this soft-shelled egg. It cracked when I picked it out of the back of the nest and I put it in a bowl I had with me, so that's why all the straw. This photo is completely unretouched except for making it smaller and was taken without a flash outside on the deck with overcast skies. I had one recently that was similar, but not quite this dark. This really is as intensely colored as it appears in the photo. Any idea what causes that? Usually, soft shells are lighter in color, not dark.
