Cormorants and shags are medium-to-large birds, with body weight in the range of 0.35–5 kilograms and wing span of 60–100 centimetres . All species are fish-eaters, catching the prey by diving from the surface. They are excellent divers, and under water they propel themselves with their feet with help from their wings; some cormorant species have been found to dive as deep as 45 m.
Cormorants nest in colonies around the shore, on trees, islets or cliffs.
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