There are conflicting ideas about the meaning of this mosaic. The most common interpretation is that this mosaic is a satirical swipe at the rather unpopular Emperor Gallus (which in Latin means “cock headed”), who, it was said, spent all his time in at the arena enjoying himself and fixing the outcome of games, rather than carrying out his duties as Caesar. A banished bureaucrat, Palladius, is believed to have been responsible for commissioning the mosaic. As he was banished for making exactly these complaints, it’s not too far fetched!
Other suggestions are that it is just a chicken, drawn by a cartoonist who wasn’t ALL that great at drawing birds, or even a representation of the god Abraxis! Make up your own mind 🙂