Great cormorants are (Phalacrocorax carbo) are impressive, large birds that can often be seen sitting on the rocks off the coast of Helsinki. Their numbers are at their highest in late summer and early autumn. Great cormorant flocks usually include a number of young, fearless birds. The great cormorant does not nest in Helsinki, but there are two colonies consisting of over a thousand pairs each in Kirkkonummi and a colony of 300 pairs in Sipoo (2016).
Great cormorants form large nesting colonies, building their nests in trees and on the ground. The great cormorant first started nesting in Finland in 1996. Their numbers have been on the rise throughout Europe and the species has spread to several new areas.
Being a fish-eating species, great cormorants sometimes cause fish envy among humans, but studies have shown that there is no cause for concern; fish stocks have not declined in any of the areas favoured by great cormorants. Great cormorant droppings smother and kill any trees in their nesting colonies in just a few years. However, they only nest on about a hundred islands out of the several hundred thousand that make up the Finnish archipelago.