Possible Clues:

• Fish seen round right channel
• That's what's so fishy about what are shortly to be found in the dugout
• Drain river to get fish out
• Deep channel in river covered in fish
• Biting insect disappears in ditch
• Banker receiving name brought about by hard depression
• One might dig R into this fish
• River fish caught in the channel
• Ditch such a coat
• Are, in short, dug out in the fish