The Diving Gannets

Around the world's coasts the gannet roams, high above the water, soaring with its long-angled wings and knife-like beak. They are one of the most spectacular species of seabirds, built for their dramatic hunting style that resembles more of a missile strike than a bird collecting its prey. Beyond their acrobatic dives, gannets are an important predator in the coastal ecosystems they inhabit, keeping fish populations balanced and transporting nutrients from sea to land. 
 
Gannets are large to medium-sized birds, recognized by their bright white feathered body, yellowish heads, and black-tipped wings. They belong to the Sulidae family (genus Morus) along with their brightly colored relatives, the booby. There are three living species of gannets: the Northern gannet, the Cape gannet, and the Australasian gannet. They get their strange name from the Old English word “ganot,” meaning strong.
 
The most unique aspect of these aerodynamic birds is their thrilling hunting style. From a mesmerizing height of roughly 100 ft (30 m), the gannet plunges headlong into the water to hunt small prey fish. They can achieve astonishing speeds of up to 60 miles per hour (97 kmh) during their free dive toward the ocean’s surface to pursue their prey. To accomplish such a feat, the birds developed a number of adaptations. Unlike most birds, they do not have external nostrils but instead breath through nostrils inside their mouths. Within their face and chest air sacs cushion the violent impact into the water like a car’s airbags. Also, their eyes are positioned far back on their pale face, allowing them to judge the proper distance accurately.
 
Not afraid of loud crowds, gannets like to breed in large colonies, with thousands of birds gathering on islands or coasts, their nests within inches of each other’s. Without a brood patch on their bellies like other seabirds, they use their greyish webbed feet to warm their chalky blue egg. Most of the time they only lay one. Gannets reach maturity around 4 to 5 years old. Juvenile gannets are mottled brown and white, lacking the bold contrast of adults. As they mature, they gradually molt into the sleek white plumage and dark wingtips of full-grown birds.
 
For centuries, people have been amused by gannets’ bold and sometimes clumsy behavior. Early sailors found them surprisingly tame, and as far back as the Iron Age, young gannets were used as food named Guga in parts of Scotland.
 
The Northern, Cape, and Australasian gannets are almost identical to the untrained eye and differ primarily in where they live and in extremely subtle differences in their feathers.
 
The Northern Gannet (Morus bassanus)
Not only is it the largest species of the gannets, but the Northern gannet also takes the trophy for biggest seabird in the North Atlantic, weighing up to eight pounds (3.6 kg) and controlling a wingspan of 6.5 feet (2 m). It spends its time cruising the coasts of the North Atlantic, preferring to breed on cliffs in Western Europe and northeast North America. The largest nesting grounds of these streamlined birds are Bass Rock, St Kilda, and Ailsa Craig in Scotland and Bonaventure Island in Canada. Due to the enormous number of birds in a single colony, the Northern gannet can get agitated when nesting, aggressively poking other birds with their long, sharp beaks. The males hunt for nest material such as seaweed, plants, and debris from the sea, to make a comfortable place for the female to lay her egg. While aggressive to others, if a pair matches up, they remain loyal, both working hard to raise their chick. Like all gannets, they dive for their prey, eating any small fish like sardines, anchovies, and haddock.

The Australasian Gannet (Morus serrator)
Closely related to the Cape and Northern Gannet, the Australasian gannet is found mainly in Australia and New Zealand, flying high around the continental shelf. In Māori, an Eastern Polynesian language, the bird is known as the tākapu. Social, they like to join large colonies when breeding or hunting on mostly offshore islands like Lawrence Rock in Victoria, Australia, or Pedra Branca near Tasmania. They differ from their Atlantic-dwelling Northern gannet relatives in a few small ways. The Australasian gannet is slightly smaller, has blacker on their tail and rear body, and a few sharper facial markings.
 
The Cape Gannet (Morus capensis)
The Cape gannet is found exclusively around the Benguela Current region off the coasts of South Africa and Namibia, where the cool water supports their swimming buffet of sardines and anchovies. They are particular about where they like to breed, preferring only a few offshore islands like Bird Island or Malgas Island. What separates them visually from the Northern and Australasian gannet is their richer, more golden-yellow head and darker facial markings