While Donald bounces backwards on the frozen pond, his hat disappears.
After Donald Duck gets hit in the face by a snowball, he goes flying backwards headfirst and crashes through the snow wall. You can briefly see his blue sailor hat before he crashes inside his fort which disappears after he sneezes the snow off his face.
After Donald Duck gets bombarded by snow bombs raining down on him with mouse traps inside slamming his head and rear end down. A mouse trap gets caught on his tail feathers. Donald's head pops out with a mouse trap caught on Donald's beak and both hands. When Donald jumps out in anger. The mouse trap caught on his tail disappears.
In the beginning, Donald Duck opens the door and his beak is frozen blue and gets his fur coat. When he's outside, his beak remains orange throughout the rest of the cartoon and his three nephews only wear sweaters and their beaks are orange.
After Donald Duck hits his nephews with snowballs and turns them into bowling pins. He makes his snowball a bowling ball and throws it underneath him to strike his 3 nephews. This wouldn't work as his bowling snowball would fall on the ground and it wouldn't be strong enough to strike three of his nephews and would crumble.
After Donald Duck loses to his 3 nephews, he falls in the icy lake and becomes a frozen ice statue, his 3 nephews dance around him and the short ends. It's unknown if Donald Duck ever got rescued by his 3 nephews and taken inside to be thawed from his ice prison.