The Wren Hunt (without harming the bird) is still carried on here in Ireland on this day. The link below goes to an article on the Wren Hunt generally in Celtic mythology.
Monday 26 December 2016
HUNTING THE WREN
Today is St Stephen's Day, the day the wren was officially hunted, probably as a leftover from Celtic paganism. Originally the wren was killed, but this no longer happens. The wren is accounted the King of Birds in a folktale which goes as follows. The birds agreed that whichever bird could fly highest would be king. The Eagle thought this was in the bag as far as he was concerned, but the crafty Wren perched on the Eagle's head and, when the large bird had reached his highest, the Wren took off and flew a few inches higher, thus attaining the monarchy.