Related Clues:

• River critters
• Playful water critters
• Swine, it's said, abandoning river to web-footed creatures
• River-dwelling mammals
• They're set to return. plunging in river?
• Playful mammals
• Playful critters
• Black furs
• Mammals that congregate in groups called 'rafts'
• Bad people not right at the outset, beasts
• Frolicking aquatic animals
• Cove critters
• Aquatic creatures returning fight around river
• Their dens are called couches
• Martens' cousins