Loons | Gaviidae

Duikers | Colimbos

The red eye and a clear, goggle-like third eyelid give loons exceptionally sharp underwater vision, letting them make out a fish several metres down and seize it with a quick lunge. A breeding pair returns to the same lake year after year and often keeps the same mate for life, though an intruding rival is fought off fiercely to defend the territory. The far-carrying nighttime wails and yodels mark out that territory and are often delivered as a tightly synchronised duet between partners, using at least four distinct call types that each carry a different message. The chicks can swim within hours of hatching but are still fed half-digested fish for the first weeks and stay close to their parents to avoid large predatory fish and snapping turtles.