A kingfisher hunts by perching very still on a branch or a rock above the water, staring down with one eye tilted to spot a fish below the surface. The moment it sees one, it plunges in at up to 40 kilometres per hour, snapping the fish in its dagger-like beak. The whole dive takes less than a second.
Kingfishers are specially adapted for this. Their eyes have two layers of protection so they can see underwater clearly. Their streamlined body and beak cut through the surface with hardly a splash. When they bring a fish back to the perch, they beat it against the branch to stun it before swallowing it whole, always head first.
In Luxembourg, kingfishers live along the Alzette, Sûre, Our and other clear rivers — especially the streams of the Mullerthal. They need clean water with small fish in it, which is why they are a good sign that a river is healthy.
Kingfishers nest in burrows they dig themselves in sandy riverbanks. The tunnel can be 60 centimetres long, ending in a round nesting chamber. Both parents take turns looking after the eggs and bringing fish to the chicks, who can eat their own body weight in fish every day.