Related Clues:

• Ocean obstacle
• Swirl around
• Sea hazard
• Snorkeling destination, perhaps
• Current event
• Rafting hazard
• Hazard to navigation
• A kind of knot
• Boating hazard
• Great Barrier, e.g.
• Singer Nelson
• Nelson or Mary Baker
• The Christian Science Monitor founder
• Site of a shipwreck, perhaps
• Water whirled?