A term used in basketball in an instance such as this: One's team is playing offense and turns the ball over (loses it to the other team by losing control, etc.) and one, out of laziness or for strategy, does not run to the other end to play defense. Usually the person snowbirding does so in order to recieve a long pass from the opponent's end in order to score before the opposing team knows what's going on. Or one is too tired to run to the other end and is just being lazy.

(ed: anyone have a better explanation - step right up!)