Go Compare

In the past, I have been asked 'What is the difference between a shag and a cormorant?'.

Today, these two posed perfectly to illustrate that difference.
The larger cormorant (Phalacrocorax carbo) is behind.the smaller shag (Phalacrocorax aristotelis).

I set the camera to over-expose so that the nuances and detail may be seen in the dark plumage of both birds. The shag clearly has a green sheen to its plumage. Note too that the cormorant's eye (iris) has a blue tint whereas the shag's is green - but will you ever get close enough to use that as an identifier?