Golden owl

"... the usual twelve Christmas trees in the Great Hall were bedecked with everything from luminous holly berries to real, hooting, golden owls."

- Harry Potter noticing the stunning decorations at Hogwarts

The golden owl was a type of owl found in the magic world. In December 1994, Hogwarts wanted to impress their fellow magic schools who were attending the Triwizard Tournament, and decorated every Christmas tree in the Great Hall with real, golden owls that hooted.