PROCELLARIIFORM

also called tubinares (order Procellariiformes), any of the seabirds that include the albatrosses (family Diomedeidae); shearwaters, fulmars, prions, and large petrels (Procellariidae); storm petrels (Hydrobatidae); and diving petrels (Pelecanoididae). There are approximately 87 living and 36 fossil species of diverse sizes and ranges. All Procellariiformes are recognizable by their conspicuous tubular nostrils, which project upon the culmen (upper bill). This feature gives the order its alternative name, Tubinares, meaning tube nosed. The feet of the birds are webbed, and the hind toe is either vestigial or missing. All species have a characteristic powerful musky odour, which is caused by the excretion of stomach oil. The oil can be used as a defensive discharge through the mouth when the bird becomes alarmed. also called Tubinares (order Procellariiformes), any of the seabirds that include the albatrosses (family Diomedeidae), shearwaters, fulmars, prions, and large petrels (Procellariidae), storm petrels (Hydrobatidae), and diving petrels (Pelecanoididae). The significant characteristics of procellariiforms are large tubular nostrils on the upper bill (the unique and unifying trait of the order), webbed feet, and a vestigial or missing hind toe. The natural habitat of procellariiforms is the Southern Hemisphere, but some are known to migrate north across the Equator to spend winters in the northern summer seas, returning home in the southern spring. Tubinares, or tube-nosed birds, are best adapted for flying at sea. On land they are clumsy and subject to predators because their legs are placed far back on their bodies and provide inadequate balance. Some species require a long runway to take flight, but in the air they become marvels of balance and grace. Albatrosses, for example, stay aloft using long glides that are only occasionally punctuated by wingbeats. Smaller birds, including petrels and shearwaters, use more frequent flapping and shorter glides. Shearwaters, storm petrels, and diving petrels make short dives to feed on small fish and crustaceans found close to the water's surface. Albatrosses, fulmars, and giant petrels are not primarily diving feeders; they consume food that is found on the water's surface including squid, fish, and ship garbage. Some islands are heavily populated with breeding procellariiforms. Mature adults return to established breeding sites and deposit a single white egg, which incubates from 40 to 80 days. The parents always nest in the same spot and remain faithful to it and each other. Breeding bird pairs stage an elaborate greeting ceremony, clacking their bills and screaming excitedly. The newly hatched chick requires parental warmth for the first week or so, after which its rapidly growing down protects it while the parents forage for food, sometimes flying hundreds of miles to find it. The fledgling eventually flies out to sea along the traditional migration route, alone and unguided. Procellariiforms are not brightly coloured, usually being black, white, brown, or gray. They often have striking feather patterns of dark and light. Most varieties have long wings, short necks, and short tails and legs. The bill is short to medium in length with single or double nostrils, depending upon the species. The human exploitation of procellariiforms for feathers, food, and oil has resulted in the complete or partial extinction of some species. Rats, pigs, and cats also prey on them. The relatively low present demand for feathers used to make hats and the establishment of many bird sanctuaries and strict hunting regulations have removed the immediate sources of danger to these species. Additional reading R.M. Lockley, The Island (1969, reissued 1980), includes life histories of Manx shearwaters and storm petrels and the results of homing experiments, and Man Against Nature (1970), describes New Zealand tubinares and muttonbirding. Other notable works include W.B. Alexander et al., The Families and Genera of the Petrels and Their Names, Ibis, 107:401405 (1965), a taxonomic reorganization of the order Procellariiformes; P.E. Davis, The Breeding of the Storm Petrel, British Birds, 50:85101, 371384 (1957), a follow-up of an earlier study by Lockley; James Fisher, The Fulmar (1952, reissued 1984), a classic monograph; William Jameson, The Wandering Albatross (1958), a readable account of the biology of the largest albatross; R.M. Lockley, Shearwaters (1942, reissued 1961), another classic monograph; M.K. Rowan, The Greater Shearwater Puffinus gravis at Its Breeding Grounds, Ibis, 94:97121 (1952); J. Warham, The Biology of the Giant Petrel Macronectes giganteus, Auk, 79:139160 (1962); and D.B. Wingate, Discovery of Breeding Black-Capped Petrels on Hispaniola, Auk, 81:147159 (1964). R.M. Lockley The Editors of the Encyclopdia Britannica