We don’t see them often, but when we do, they’re in big trouble. The only reasons a Northern Gannet comes ashore will be injury, illness, starvation or blown off course during a storm. When one becomes too weak or unable to fly, it will float on the ocean until the tide carries it to shore. Northern Gannets are the largest indigenous seabird in the North Atlantic with wingspans of 68 – 70 inches and weighing 6 to 8 pounds. They spend most of their lives at sea. This magnificent pelagic seabird, that reaches adult maturity in five years, is known for its gorgeous pale blue eyes accentuated by a ring of bare, bluish-black skin and contrasting snow white body with black wing tips. It is strikingly beautiful! One might think that the Gannet is closely related to a Gull, but they are seabirds comprising the genus Morus in the family Sulidae which is closely related to Boobies. Gannets are among the world’s most renowned divers, truly “Masters of the Sky,” who descend from heights up to 130 feet as they plunge into the ocean like an arrow at 60 plus miles per hour. Most of the world’s population of Northern Gannets breeds off the coasts of Great Britain and Scotland, but there will be random groups of Gannets wintering off North Carolina’s coast.
Occasionally, a Gannet will be admitted to the Outer Banks Wildlife Shelter (OWLS) in Newport and upon receipt of the bird, we know it will be a touch and go situation. Recently, that was the case when a Good Samaritan rescued a beached adult Gannet that had discarded fishing line wrapped around its beak. During the examination, we were thankful there was no line going into his gullet. The staff at OWLS removed the offending trash and commenced emaciation protocol. That poor seabird was 600 grams below normal weight for an adult. Gannets are known for a voracious appetite. They have the capability of eating very large quantities of fish during a feeding, so it was obvious this Gannet was starving to death due to his beak being literally tied shut. Gannets eat sardines, anchovies, haddock, smelt, Atlantic Cod and the young of larger fish species. Squid is also a menu choice for these vertical divers. They dive into the sea with their wings and feet retracted and tucked tightly against their body. The Gannet has highly developed lungs, secondary nostrils inside their mouths that close rather than external nostrils and a long, strong sternum protecting their internal organs when impacting with the water. These features are perfect for the high speed and deep diving they are capable of. They also have a subcutaneous fat layer, dense down and tightly overlapping feathers that help them withstand low temperatures. Reduced blood flow in the webbing on their feet also helps maintain their body temperature when they swim. A Gannet’s feathers enjoy a higher level of waterproofing than other seabirds that need to dry out between foraging sessions. Northern Gannets produce an impermeable secretion in their sebaceous glands which they spread across their body using their beak or their head.
Gannets breed in large colonies along the Atlantic, and boaters have witnessed spectacular displays of plunge-diving for fish by them in the hundreds. Once beneath the water, it uses its wings and feet to swim in pursuit of a meal. They grab food with their long, strong, conical bill and always eat it under water. They never fly with a fish in their bill. Northern Gannets nest offshore, and most often, nests are found tucked into inaccessible cliffs. Some breeding colonies are recorded as being located in the same place for hundreds of years. A Gannet’s nest is definitely a testament to the value of recycling as it is constructed of compacted mud, seaweed, grasses, feathers and their own waste! The males usually collect the materials necessary for nest building. Off the coast of North Carolina, because cliffs are not available, Northern Gannets will nest on islands or flat surfaces, however, they find it more difficult to take off from these locations which requires them to often cross an area occupied by an adjacent nesting area and that can cause stress and aggression from the pair occupying a trespassed nest. Despite being a little nasty toward one another, Gannets always nest close together. There are no loners during breeding season. Northern Gannets will lay only one egg rather than 2 or 3 like most seabirds. If two eggs are found in a Gannet’s nest, it’s the result of two females laying an egg in the same nest or an egg was stolen from another nest. Incubation takes 42 to 46 days and occurs under the webbing of their feet, flooded with warming blood. An infant can take up to 36 hours to break through the thick eggshell. At this time, the adult will release the egg from its feet to prevent the egg from breaking under the adult’s massive weight. Northern Gannets learn the hard way in their first breeding year that if they aren’t cautious about that, the chick may die. The warm webbed feet are also used to cover the newborn, which is rarely left alone by the parents.
A hatchling will spend about 13 weeks in the nest with the parents where it is fed regurgitated fish and is fiercely monitored to prevent attack or death by Black-Backed Gulls, Herring Gulls, Ravens, Ermine, Red Fox or other Northern Gannets. Nature is harsh! Fledglings are brown with white wing tips, and they have white spots on their heads and backs. Once a Northern Gannet fledges from its nesting colony and is on the water, it will remain there for as long as two weeks because it has not learned how to take off from a water runway yet. While flying muscles comprise 20% total weight for most seabirds, Northern Gannets’ flying muscles are less than 13% which demands they warm up before flying and that they calculate and rely on the wind, especially wind produced by the front of a wave. Bobbing in the water is also a safer place for a youngster to be than risk accidently tripping into Gannet breeding ground. They are not sturdy on their feet as land walkers due to the location of their legs so far back on the body.
Gannets are swimmers and flyers, not walkers! The young have a fat reserve, allowing them to go without eating for up to 2 weeks, but don’t worry; the parents are still close by for further fishing and flying training. The maximum lifespan known for a Northern Gannet is 35 years. Adult Gannets are not heavily preyed upon, but when it happens at sea, an eagle, shark or seal is usually the culprit. If you ever get the rare opportunity to see Northern Gannets, savor that momentary visual gift of these “Masters of the Sky,” because it may never happen again!!
author of “Save Them All“