Possible Clues:

• Goodman, for example, consuming large fish
• British comedian Henry provides fish
• Small elongated fish
• British comedian Henry is swimmer
• Boy catching large fish
• Small spiny-finned fish with scaleless skin and a blunt head
• Spiny-finned fish
• Goodman, for example, crossing loch to get fish
• Bernstein's book on spiny-finned fish
• There's something fishy about little 17 across being about fifty