Gannets leave fish with nowhere to hide
This is the moment Britain’s largest seabird turns into a two-metre arrow. The Northern gannet angles its wings just above the water to streamline its body before breaking through the surface like a bullet. Plummeting from 30 metres up, the bird can dive to a maximum depth of ten metres. Gannets hunt in a flock, so when they dive it’s like a machine gun peppering the surface of the water.
Each bird exerts an enormous amount of energy during a dive: taking in seven seconds’ worth of air, Morus bassanus grabs a fish from the rapidly dividing shoal of herring, avoids colliding with other birds or dolphins under the water and races back to the surface. The slightest error in calculating the entry angle and the 100km/h hunter would become just a pile of feathers floating in the Atlantic.
The gannet’s entire anatomy (including closeable nostrils and a sternum that acts as a shield to protect its organs) is geared towards its kamikaze-style hunting technique. Closely related to the booby, the birds share many of their humorously monikered cousin’s idiosyncrasies. Like them, gannets waddle a bit when walking on land, but only because their feet are located towards the back of their body. Their hunting technique is also almost identical, and though their wingspan is larger at an impressive 180cm, they are similarly economical when it comes to their flight muscles. Both species use them only around 13% of the time. But does this inhibit the performance of the largest bird in the North Atlantic? Not at all! Indeed, every year, 150,000 of them glide their way to Bass Rock in Scotland’s Firth of Forth, making it home to the largest colony in the world.