A video recorded at a wildlife refuge in the midwestern United States shows half a million snow geese gathered on a lake.

The footage was recorded at the Loess Bluffs National Wildlife Refuge in Missouri.

Snow geese travel north every spring, as they make their way from warmer southern coastal areas to their breeding grounds in the colder arctic areas.

"An official survey is being conducted but there's roughly 500,000 snow geese on the refuge; split between Eagle Pool and Bluff Pool on the northeast side," the refuge said..

This footage shows the birds flocking on the lake, in a sensational show of nature.