Open Season

Feather 1: In Snow Blitz, after the falling Ice Column, jump to the ice path. It's on the ledge to the left.
Feather 2: In Snowblitz, after the ice cavern, is on the sloped ice ledge.
Feather 3: In the first part of crazy quackers, after scaring the hunter by the truck, throw elliot to the ledge.
Feather 4: In the first part of crazy quackers, cross the bridge, and take the path to the left.
Feather 5: In Fowl duty, go back to the where the two hunters were and jump to the right on the ledges.
Feather 6: In the second part of crazy Quackers, after repeating the code to the ducks. Grab elliot and throw him to the far shore.
Feather 7: In Beaver Damage, get to the stone bridge/path. Throw elliot to the left.
Feather 8: In Beaver Damage, when you have to find the replacement teeth, throw elliot onto the roof of the cabin.
Feather 9: In Beaver Damage, right after O'toole falls out of the tree and points out Boswell. Run up there, and throw elliot up to the left.
Feather 10: This is a bit tricky. In Rocky River, make it to the sandbar. Steer left around the bend and right around the outcropping. Jump to get the last feather.

*Credit to Manatee from x360a.com