Het heroisch einde van een Grote Jager Stercorarius skua

On 14th October 1989 at the Hondsbossche near Camperduin, Noord- Holland, a Great Skua was seen attacking a juvenile Herring Gull with the apparent intention of killing it. The victim was pressed down to the beach, while the skua was stabbing it in the neck. When both birds got fouled by a layer of organic foam present at the tideline, it was found that neither of them was able to fly off at our approaching and since the skua was wearing a ring, the birds were caught. The Great Skua turned out to be a five-year old individual ringed at Kvisker (63°59’N, 16°26’W), Iceland. The birds were left together in a sheltered corner of the dike. The next morning the skua had disappeared, only to be found in an exhausted state at the beach of Bergen, 4 km more to the south. Later on the bird died and the body was analyzed at the Zoological Museum of Amsterdam. It was a male in a very poor weight and fat condition with an empty stomach and an old bone fracture in the wing, probably caused by shooting. The story suggests that a bird in a poor physical condition may sometimes make a desperate and costly attempt to obtain an amount of food, large enough to overcome its present needs at once. In the case of our Great Skua, this last attempt, possibly because of a reduced killing efficiency, did not turn out well, and was the probable cause of its final exhaustion and death.