Old World cormorants

Unlike most waterfowl, their feathers are not completely waterproof, so when wet, they gain weight, allowing them to sink deeper and dive easily. Once on land, they spread their wings to dry them. In addition, they regulate the volume of their air sacs.
The great cormorant lives in lakes and estuaries, as well as on shorelines, and builds its nest on cliffs or in trees. It reaches up to 90 cm in length, and can be found in fresh waters and coasts around the world.