Wilden Marsh Cormorants

Cormorant

Cormorant

Every year, around half a dozen cormorants arrive from the coast to overwinter on Wilden Marsh Nature Reserve. They spend most of their time perched high up on power cables overlooking the river, until something happens to encourages them move.

Cormorants are fish-eaters. They dive from the surface, though many species make a characteristic half-jump as they dive, presumably to give themselves a more streamlined entry into the water. Under water they propel themselves with their feet, though some also propel themselves with their wings.

After fishing, cormorants go ashore and are frequently seen holding their wings out in the sun. All cormorants have preen gland secretions that are used ostensibly to keep the feathers waterproof. Some sources state that cormorants have waterproof feathers while others say that they have water permeable feathers. Still others suggest that the outer plumage absorbs water but does not permit it to penetrate the layer of air next to the skin. Alternate functions suggested for the spread-wing posture include that it aids thermoregulation or digestion, balances the bird, or indicates the presence of fish. A detailed study of the great cormorant concludes that it is without doubt to dry the plumage.

Cormorants are colonial nesters, using trees, rocky islets, or cliffs. The eggs are a chalky-blue colour. There is usually one brood a year. The young are fed through regurgitation. They typically have deep, ungainly bills, showing a greater resemblance to those of the pelicans, to which they are related, than is obvious in the adults.

3 Comments on “Wilden Marsh Cormorants

Leave a Reply

%d bloggers like this: