According to the University of Delaware, YoUDee's colors are Gold and Blue because his great-great-great-grandfather was awarded the Gold Medal for Valor during the Battle of Trenton in the American Revolutionary War. The men in the company commanded by Captain Jonathan Caldwell actually carried Blue Hens with them into combat in order to hold cockfights in their spare time. It is said that the men under Capt. Caldwell fought so bravely that they were compared to their fighting blue hen chickens.
On August 16, 2006 YoUDee was inducted into the Mascot Hall of Fame, in a ceremony at Philadelphia's Love Park. YoUDee has won the mascot national championship a total of 7 times, his latest coming in 2017.