Possible Clues:

• Bambi, in the book
• Felix Salten’s Bambi, e.g
• Creature in river heartless rower traps
• Native wild animal
• Animal route present in the East End?
• Buck's sound advice for sweetheart in punt?
• Animal paddled here by the sound of it
• Eurasian animal with antlers
• Beast came by 'orse, we hear
• Caviar expensive, it's said? It may be a buck