Corn predators & ripening

As the time to harvest corn for seed has come, I've noticed that some of the Blue Aztec, has been eaten by something.  The chickens are too dumb to know to peel back the corn to get to the kernels.  What has eaten the corn?  Rabbits?  Hares?  Magpies?  Something else?

It must be something ground-based.  Here's a Bloody Butcher cob which I peeled back, which is perhaps 1.5 meters off the ground.  I figured that pulling back the husk on this cob would serve a few purposes.  Firstly, if there were birds eating it, they'd easily find it and have a go.  And secondly, I'd be able to see if it would make a difference in ripening it from a yellow colour to the dark red it should be when dried.  It's been exposed for a week, and has gained some redness as can be seen.

The Bloody Butcher gave consistently big cobs.  Most of them are still on the stalks, as few have ripened sufficiently.  I'm not sure how well they'll do in the frosts.  And I'm not sure if they will ripen, or produce viable seed, if I tear them all out and dry them in the shed.