A barrel-chested outline reveals the presence of one of our more powerful seabirds – the Great Skua or ‘bonxie’ as it is known to many birdwatchers. Today, with the full force of the north wind coming in off the sea, we are fortunate enough to see a number of these magnificent birds (including a party of five together) as we crunch our way out to the point.
These are the largest and most powerful skuas; related to the more familiar gulls they are often described as the pirates of the sea, robbing other seabirds of food and stealing chicks and eggs. Another source of food, in the form of fishery discards, has been particularly important for the bonxies, allowing their population to recover from decades of persecution (young bonxies were taken from the nest, fattened up and then eaten) and expand. With 60% of a global population of some 16,000 pairs, Scotland is an extremely important breeding area for these birds and they seem to be doing ok, although there is some concern over the very high levels of heavy metal and organochlorine pesticide residues found in their body tissues. As top predators, these skuas make good bioindicators of the wider condition of the marine environment.
The skuas move south in the autumn to winter in more favourable conditions south to the Bay of Biscay and into the western end of the Mediterranean. It is during this period of autumn passage that you may see them along the Norfolk coast, often singly but occasionally in larger groups. Like many of the other seabirds passing through on passage, the best chance of viewing them comes when the winds are strong and onshore. Most of those breeding in Scotland pass down the western side of the country but some do exit the North Sea via the English Channel and it is these birds that pass through the county’s waters.
Interestingly, some Great Skuas take short cuts by heading overland and it is not uncommon to see birds heading into the Wash and then gaining height to strike purposefully inland, following the Nene or the Ouse. This behaviour explains the presence of a Great Skua just last week at Graffham Water.
Great Skuas are fairly obvious and easy to identify, not least because they have a distinct profile. As well as the barrel-chest already mentioned, these thick-set birds have short but broad wings, with a distinctive white crescent often visible at the base of their main wing feathers. As for the name ‘bonxie’; well, it is thought to come from the old Norse word ‘bunki’, from which is derived the Shetland term ‘bunski’ often applied to a dumpy or heavily clothed woman.