It was a harsh time for paddle boarders attempting get their paddle on at Swan River in Perth, Australia on Saturday.Hundreds of hungry salmon swooped in to feed on a school of smaller fish, turning the calm river water into a bubbling frenzy. Caroline Bradley, owner of Elemental SUP, a stand up paddle boarding school in Perth, filmed the encounter, which inevitably cancelled the lesson that morning. "It looked like the water was boiling. It was unreal, I was lucky I had the camera at hand," Bradley told WAToday.