Loons, with their striking appearance and haunting calls, are birds deeply connected to aquatic environments. These fascinating birds spend most of their lives on freshwater lakes during breeding season and coastal waters in winter. The unique adaptations that make loons exceptional in water significantly limit their mobility on solid ground.
Built for the Water
Loons possess several anatomical features that make them incredibly efficient swimmers and divers. Unlike most birds, which have hollow bones for lighter flight, many of a loon’s bones are solid. This increased bone density reduces buoyancy, allowing them to submerge and dive with less effort. Their bodies are streamlined, resembling a torpedo shape, which helps them glide smoothly through water.
The legs of a loon are positioned far back on their bodies, functioning like powerful propellers. This rearward placement, combined with large, webbed feet, provides maximum thrust for underwater propulsion. These adaptations enable loons to dive to depths of up to 200 feet and stay submerged for extended periods, sometimes over a minute.
On Land: A Different Story
The very features that make loons superb underwater hunters render them awkward on land. Due to their legs being set so far back, loons cannot stand upright or walk in the way most birds do. Their bodies are not designed to support their weight on two legs in an upright posture.
When loons do move on land, they must push themselves forward on their chests and bellies. This method involves a shuffling or sliding motion, often using their feet to propel themselves while their body remains low to the ground. This terrestrial movement is slow, cumbersome, and exposes them to predators, contrasting sharply with their graceful agility in water.
When Loons Come Ashore
Only venturing onto land for specific and limited reasons, the primary reason for a loon to come ashore is for nesting and raising their young. They select secluded nesting sites very close to the water’s edge, often on islands, in marshy areas, or on shores with a steep drop-off, to minimize the distance they need to travel on land.
Both male and female loons participate in building a nest, typically a mound of dead plant material, and incubate their one or two eggs for about 28 days. Once the chicks hatch, they are precocial, meaning they can swim and dive within hours. Loons are generally only on land during this breeding season, which usually occurs from May to early June, and return to the water as soon as possible.