Another way to tell the stage of maturity is by the feathering. Gilbert still has some little baby down on his neck and top of his head. This will disappear soon until his whole neck is smooth black feathers. When the wings are finished, you will see the long flight feathers held on his back. They will reach almost as far as his tail.
This is the group I've been watching. You can see just little bits of the baby fuzz on some of their necks. A couple have gone all black now. You can see the wings are short over their backs - when the flight feathers grow in they will extend all the way across their back. When they open their wings now, they look fully feathered. But are still lacking the long flight feathers on the ends.
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If he does figure out how to fly, it may be some cause for worry - in case he flies off a ways and doesn't know how to get back home, or you lose him. He won't have learned how to stay safe maybe?
There's a movie I really enjoyed that taught me some things about what geese need. "Fly Away Home." Maybe you've seen it. It's based on a true story of a man who took in some geese in Canada, and then taught them how to migrate.
It's on Hulu and Amazon - and can get DVD from Amazon.
Fly Away Home
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