Double-Crested Cormorant

Fascinating facts about the Double-Crested Cormorant

• A double-crested cormorant can dive to 25 metres and stay underwater for up to 60 seconds — yet unlike every other diving bird, its feathers aren't waterproof. Instead, they absorb water, making the bird heavier and less buoyant, so it sinks like a stone instead of fighting to stay down. After hunting, it must spend hours perched with wings spread open to dry out, a behaviour called 'wing-drying' that looks awkward but is perfectly engineered for pursuit diving.
• Cormorants have eyes that can see clearly underwater but are nearly short-sighted on land — the opposite of most birds. They've evolved a lens that shifts shape dramatically when diving, bending light the way a snorkel mask does. This trade-off means they navigate by instinct and memory between dives, relying on muscle memory of where they've hunted before.
• The 'crests' on their heads appear only during breeding season, when males grow two feathery tufts above their ears. These crests are so temporary that outside of spring and early summer, the bird looks completely bald-headed. The ornament vanishes within weeks of breeding season ending — a biological timer that syncs appearance to mating opportunity.
• A single double-crested cormorant eats roughly 250 to 300 grams of fish per day, making it one of North America's most efficient fish hunters. A breeding colony of just 1,000 birds removes about 90 tonnes of fish annually from a lake or river system. This appetite once made them villains to fisheries managers, who killed thousands in the mid-20th century, but the birds have rebounded so successfully that some populations now number in the hundreds of thousands.
• Cormorants are so efficient at fishing that they've become markers of water quality across North America — wildlife scientists use population counts and breeding success as a barometer for healthy fish stocks and ecosystem recovery. Their return to rivers and lakes where they were once extirpated signals that the water can support abundant life again, making them living evidence of environmental healing.

At a glance

About the Double-Crested Cormorant

In the misty dawn, the Double-Crested Cormorant emerges, its sleek, ebony form slicing through the water with effortless precision, as if gliding across the liquid expanse on an invisible thread. With each powerful stroke of its wings, it propels itself forward, a master of the aquatic realm, its piercing gaze scanning the depths below for the telltale flash of a fish. As it rises, a solitary figure, to perch upon a weathered rock or branch, its crested crown a proud declaration of its dominance over this shimmering, sun-kissed world.

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