Related Clues:

• Fell from bird-watchers' retreat
• Having a hundred-odd acres, so bound to be conventional?
• Herbie, ex-heavyweight champion
• Breed of duck
• Herbie, who won a version of the world heavyweight title
• Down here, Princess said
• Keep secret, skin
• Place to observe wildlife in park's sound
• Mammal's tough skin
• Deer roaming round One Down's source
• Downy sea duck
• Reportedly a doctor's alter ego's cloak
• Sea bird about to go west goes the other way
• Down-producing duck
• Duck shows hesitation eating fish