Invasive species Part 3 - The Cormorant-not invasive

After cormorants have taken over an island in the Stockholm archipelago, it isn’t a pretty sight. The vegetation dies and the ground is covered in a blanket of grey droppings. It looks horrible and it smells worse. And on top of that, professional fishermen and anglers say the birds are eating too many fish.

Some people hate cormorants so much that they say they are an invasive species in Sweden and that they must have been imported from China or brought in by some landowner in Småland.

It’s true that the odd cormorant might have arrived that way, but traces of cormorants have been found in Europe dating back several thousand years and, far from being imported, the birds themselves fly to Africa for the winter and fly back again. 

In Sweden, cormorants were virtually hunted to extinction in the late nineteenth century. At that point, so many had been hunted and killed that the species couldn’t survive. But then they returned. Slowly at first, but since the late 1980s they have spread along much of the Swedish coastline.

But invasive? No. It’s true they can cause quite a lot of problems in the places they settle, but then again, who doesn’t?  It’s not as if humans are totally innocent of causing problems in the natural environment.