Ryan Photographic - Sulidae - Gannets and boobies

Family Sulidae

The family Sulidae contains ten species in three genera. The gannets, typically temperate region birds, are placed in the genus Morus while the boobies, more tropical and sub-tropical, are in the genus Sula. A third genus, Papasula, was erected for Abbott's booby.

The sulids are typically plunge divers. To accommodate this behavior they lack strongly developed breast muscles and as a result have a high wing loading. Sulids hit the water at speeds of up to 88 kph (55 mph). The sharp beak breaks the water surface and the very long neck compresses slightly. An airbubble forms around the neck (and may more or less eliminate drag from the water aka the Russian Squall torpedoes). If they miss their prey (fish or squid) they may swim after them using both legs and wings. More information about their diving can be found here. They are large birds with wingspans reaching nearly 175 cm. More information about their distribution and habits is available on Wikipedia.

Morus serrator Australasian gannet

Morus serrator, Australasian gannet at Cape Kidnappers, New Zealand

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