Great cormorant

The great cormorant or great black cormorant is widespread across the northern hemisphere. Size varies across the range it is found. The great cormorant has a distinguishable black body (without a green tinge), white cheek-patches and a yellow spot next to the beak (all wiki). All the individuals I've spotted have green/turquiose irises. I don't know if this is typical of the species or a local variety.