Divers | Gaviiformes

Duikers | Colimbos

The whole body is set up for swimming down fish under water: the legs are placed right at the rear, the tarsi are flattened sideways like a blade, they project only a short way beyond the body, and the three front toes are fully webbed. The bones are heavier and less filled with air than in most birds, so little effort is needed to go down; by squeezing the air out of the plumage the bird can sink away without a splash. That same build makes walking all but impossible — on land they shove themselves along on the breast — so they come ashore only at the water's edge and, in nearly all species, can take off from water alone, after a long running start.

Families in this order

Divers | Gaviidae5 speciesIn summer a crisply patterned black-and-white plumage with striped or chequered upperparts and a coloured throat patch; in winter plain grey-brown above and white below, and in that season all the flight feathers are shed at once, leaving the birds unable to fly for some weeks. They swim low in the water with the pointed bill held level or slightly raised and fish by sight in clear water, seizing prey with a quick stab. The nest is a heap of wet vegetation right at the water's edge or a floating raft; almost always two darkly blotched eggs are laid, and the young take to the water within a day and ride on the parents' backs for the first few days. In flight the silhouette is hunchbacked, the neck drooping slightly and the big feet projecting past the tail, with fast, unbroken wingbeats and no gliding.