Great Cormorants have special feathers which allow air to escape and water to penetrate the plumage. Underwater, swimming is more efficient. But it means that the bird has to dry its plumage in a characteristic posture, with wings spread out, perched on a branch. This pose may also help to digestion. It consumes about 400 to 700 grams of fish per day.
<a href="//commons.wikimedia.org/wiki/User:Shiv%27s_fotografia" title="User:Shiv's fotografia">Shiv's fotografia</a>
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<span class="int-own-work" lang="en">Own work</span>