His real name is Montague, but he is usually called Duck, which he prefers. This is said to be because he waddles, though he does not really. Duck stands for no nonsense from any engines that might get ideas above their station and try to order him or others about. Duck is often welcoming of newcomers, even most Diesels, in spite of having lies told about him by devious Diesel not long after his arrival. He will often support the underdog, stick up for his friends, and help others see the error of their ways. He has a branchline which was restored and Duck was asked to run it with help from Oliver and, on occasion, Donald and Douglas.
Duck is a GWR 5700 pannier tank engine with added sandboxes.
- Escape (cameo)
- Oliver's Determination
- The Story of Adam
- Percy Plows The Field (cameo)
- Pop Goes The Diesel
- Diesel's Devious Deed
- Close Shave For Duck
- Thomas and Oliver (cameo)
- JD41796 (episodes 3, 4, and Little Western Rescue only)
- Terrier672Fenchurch (episodes 8-10 and Thieves and Whistles only)
- FantasticMrS (season 2 onwards)