Britain’s largest seabird can travel hundreds of miles from their nests just to catch food for their chicks.
The birds use their excellent eyesight to spot schools of fish below the surface of the water and dive at speeds of up to 62mph. But with around one million square miles of ocean to choose from, it has always been a mystery how they decide where is best to search for fish.
Scientists at the University of Glasgow recorded thousands of gannets commuting to and from the Bass Rock – the rocky island 2.5 miles from North Berwick in East Lothian – that is home to an estimated 75,300 breeding pairs.
The researchers discovered the more experienced adult birds were often found at the front of commuting flocks, with younger birds following behind.
The results, published yesterday in the Journal of Avian Biology, suggest travelling as part of a flock is about more than just gaining aerodynamic benefits. The findings add weight to the theory that gannets learn to hunt by following their elders. Dr Ewan Wakefield, from the University of Glasgow’s Institute of Biodiversity, Animal Health and Comparative Medicine, said: “By demonstrating that young gannets follow more experienced adults, we have shown that knowledge about the best feeding grounds may be being passed down from generation to generation.”
Gannets commuting to and from the Bass Rock were observed from a series of vantage points – the Isle of May, Fife Ness and St Abbs Head.
The researchers then modelled how frequently the gannets travelled in flocks, the sizes of those flocks and the positions of young and adult birds.
Many birds, including geese, swans and cranes, travel in flocks for a number of reasons, including to reduce aerodynamic drag and therefore save energy.
In addition, travelling in a group can improve hunting efficiency, navigational accuracy and predator avoidance.
The gannet research demonstrates that travelling in flocks may also facilitate social learning. Dr Wakefield said: “The ability to tap into this communal wisdom may also go some way to explain why gannets and other seabirds breed in such huge colonies.”
Scotland is internationally important for its seabirds, including more than 60 per cent of the world’s northern gannets.
The animal is Britain’s largest seabird, with a wing span of more than 6ft.