Something Wicked This Way

The egg had not split open as in a hatching process, only a smallish sized, elongated hole was seen on one side of the egg. Inside a small amount of yolk was smeared across the interior.
This was the work of fowl play (pardon the pun, I’m just in that kind of mood).
It would be my guess that a predator in the form a larger bird than a robin, stole the egg from the next and used the bridge as his dinner table while he punched a hole and sucked out the embryo. Springtime can be a wicked season for those that are not on guard.