Most geese are generally gregarious birds who form flocks during migration and outside of the breeding season. If you've seen a flock of geese, you may already know that they can be rather noisy, but that is the collective noun for a group of geese?

Geese have many different collective nouns, which change depending on where they are. For example, when on the ground or in the water, they are often referred to as a gaggle of geese. In flight, a group of geese is called a skein, team or wedge. On the water or flying close together, a wedge of geese.

More Info: birdfact.com