As a sequel to the RSPB’s gannet and puffin cruises off Bempton Cliffs, Yorkshire, yesterday, we took a ‘migration cruise’ in the hope of seeing some rarer seabirds running south down Yorkshire’s coastline. We were three hours at sea and saw little of interest until the last half hour when, attracted by great black-backed gulls (the largest gulls in the world, I believe) and the occasional herring gull following the boat, two juvenile great skuas (bonxies) turned up. Bonxies are kleptoparasitic birds which, in plain language, means they rob others of their catch. Smaller than the great black-backed and about the same size as a herring gull, they are fearless and very aggressive, attacking and sometimes killing the larger birds in order to relieve them of their meal. Here are a few images of both, including some pursuits and altercations between these two species. The bonxies are the brown ones. The brownish gulls with black bills are juvenile great black-backed.