The Pirate of the Skies

A powerful and aggressive bird - the pirate of the skies could be deemed one of Britain's most formidable seabirds. 

With a heavy body, dark brown plumage, and broad wings marked by flashes of white plumage, the Great Skua is a powerful predator. It weighs about 1.4kilograms and has a wingspan of approximately 1.3 metres. It has been known to swoop directly at people - including at me. 

In Shetland, the Great Skua is called Bonxie, and Britain is important for the species because approximately 65% of the world's breeding population is found in Britain and Ireland. The Great Skua can be seen in northern and western Scotland and, in particular, on Shetland and Orkney islands. 

A Great Skua will harass and chase other seabirds until food is either regurgitated or a fresh catch is dropped. This predatory move is why it's given the name pirate, but they hunt small birds, rodents, rabbits and can even take fish. These are opportunistic feeders, and can change their diet to whatever is available, even hunting and eating puffins if they can. Kittiwakes and guillemots are common victims of Great Skua bullying. These birds usually drop any food rather than be preyed upon.

Great Skuas have even been seen targeting gannets too, sometimes grabbing their wingtips so the bird falls into the sea. Gannets are more capable of fending off Great Skuas, though. 

Breeding

When I saw my first Great Skua, I was on a boat, and this impressive-sized bird flew alongside us. I was warned to be careful and to wear a hat when on land, and once we docked, we were following a set path up through the island, mindful that there could be breeding birds nearby. The Great Skua, which comes ashore to breed, took great offence at our presence. I am glad we were told to wear hats because they aggressively swooped and one skimmed my head. They have been known to draw blood and are highly territorial. They were not to know, of course, that we were bird lovers.  They nest on coastal moorland, and the nest is a simple grass-lined scrape. Two eggs are typically laid. 

Males and females develop strong, lifelong bonds and perform aerial displays in spring, gliding side by side and calling to each other.  During egg-laying, males will bring food gifts to the female, who begs for the food, similar to the chicks begging. 

Great Skuas do not generally begin breeding until about seven years old, and the species, on average, lives for 15 years, although much older birds have been recorded. 

Bird flu

Sadly, the Great Skua population was hit by bird flu in 2021 and 2022, with about 76% of the population being affected. The full consequences are not known.  But bird flu is not the only threat; climate change is too. Global warming could make breeding areas unsuitable. 

Now a Red-Listed bird of Conservation Concern, we must protect this species. Yes, it is a predator, a bully, a feathered pirate of the seas, but it is also an intricate and vital part of the web of life. 

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