Pelican - Wikipedia. Pelicans are a genus of large water birds that makes up the family. Chapter 34 - Psychosocial and Organizational Factors PSYCHOSOCIAL AND ORGANIZATIONAL FACTORS. Hurrell Jr., Lawrence R. Murphy and Lennart Levi. Pelecanidae. They are characterised by a long beak and a large throat pouch used for catching prey and draining water from the scooped up contents before swallowing. They have predominantly pale plumage, the exceptions being the brown and Peruvian pelicans. London, England, 23 September 1939) psychology. Freud’s father, Jakob, was a. Human Capital and Sustainable Economic Growth. Research on sustainability focuses largely on the carrying capacity of the environment and the deleterious impact of. In response to Shuter's (Shuter, 1990) call for the examination of communicative phenomena in particular societies worldwide, this article critically reviews the. BibMe Free Bibliography & Citation Maker - MLA, APA, Chicago, Harvard. The bills, pouches and bare facial skin of all species become brightly coloured before the breeding season. The eight living pelican species have a patchy global distribution, ranging latitudinally from the tropics to the temperate zone, though they are absent from interior South America as well as from polar regions and the open ocean. Long thought to be related to frigatebirds, cormorants, tropicbirds, gannets and boobies, pelicans instead are now known to be most closely related to the shoebill and hamerkop, and are placed in the order Pelecaniformes. Ibises, spoonbills, herons and the desolate bitterns have been classified in the same order. Fossil evidence of pelicans dates back to at least 3. Oligocene strata in France. They are thought to have evolved in the Old World and spread into the Americas; this is reflected in the relationships within the genus as the eight species divide into Old World and New World lineages. Pelicans frequent inland and coastal waters where they feed principally on fish, catching them at or near the water surface. They are gregarious birds, travelling in flocks, hunting cooperatively and breeding colonially. Four white- plumaged species tend to nest on the ground, and four brown or grey- plumaged species nest mainly in trees. The relationship between pelicans and people has often been contentious. The birds have been persecuted because of their perceived competition with commercial and recreational fishing. Their populations have fallen through habitat destruction, disturbance and environmental pollution, and three species are of conservation concern. They also have a long history of cultural significance in mythology, and in Christian and heraldiciconography. Taxonomy and systematics. He described the distinguishing characteristics as a straight bill hooked at the tip, linear nostrils, a bare face, and fully webbed feet. This early definition included frigatebirds, cormorants, and sulids as well as pelicans. Tropicbirds, darters, cormorants, gannets, boobies and frigatebirds, all traditional members of the order, have since been reclassified: tropicbirds into their own order, Phaethontiformes, and the remainder into Suliformes. In their place, herons, ibises, spoonbills, the hamerkop and the shoebill have now been transferred into Pelecaniformes. The largely marine brown and Peruvian pelicans, formerly considered conspecific. The Dalmatian, pink- backed and spot- billed were all closely related to one another, while the Australian white pelican was their next- closest relative. The great white pelican also belonged to this lineage but was the first to diverge from the common ancestor of the other four species. This finding suggests that pelicans evolved in the Old World and spread into the Americas, and that preference for tree- or ground- nesting is more related to size than genetics. Inland North America, wintering in Mexico. Coastal distribution ranging from North America and the Caribbean to northern South America and the Galapagos. Pacific Coast of South America from Ecuador and Peru south through to southern Chile. Patchy distribution from eastern Mediterranean east to Indochina and Malay Peninsula, and south to South Africa. Social Science Dictionary with a Durkheim bias, linked to Andrew Roberts' Social Science History. The Inspiration - There's more to batteries than you might think. We think of a battery today as a source of portable power, but it is no exaggeration to. INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY ENVIRONMENTAL HEALTH CRITERIA 52 TOLUENE This report contains the collective views of an international group of. Australia and New Guinea; vagrant to New Zealand, Solomons, Bismarck Archipelago, Fiji and Wallacea. Africa, Seychelles and southwestern Arabia. South- eastern Europe to India and China. Southern Asia from southern Pakistan across India east to Indonesia. This species will nest on the ground when no suitable trees are available. The slender rami of the lower bill and the flexible tongue muscles form the pouch into a basket for catching fish and, sometimes, rainwater. Although they are among the heaviest of flying birds. The wings are long and broad, suitably shaped for soaring and gliding flight, and have the unusually large number of 3. The largest is believed to be the Dalmatian, at up to 1. The Australian pelican's bill may grow up to 0. The American white pelican grows a prominent knob on its bill that is shed once females have laid eggs. They primarily inhabit warm regions, although breeding ranges extend to latitudes of 4. They rub the backs of their heads on their preen glands to pick up an oily secretion, which they transfer to their plumage to waterproof it. Thus they use thermals for soaring to heights of 3. As the air flows between the wings and the water surface it is compressed to a higher density and exerts a stronger upward force against the bird above. Agonistic behaviour consists of thrusting and snapping at opponents with their bills, or lifting and waving their wings in a threatening manner. Nearer the shore, several will encircle schools of small fish or form a line to drive them into the shallows, beating their wings on the water surface and then scooping up the prey. This operation takes up to a minute, during which time other seabirds may steal the fish. Large fish are caught with the bill- tip, then tossed up in the air to be caught and slid into the gullet head- first. A gull will sometimes stand on the pelican's head, peck it to distraction, and grab a fish from the open bill. James's Park in London. Pairs are monogamous for a single season, but the pair bond extends only to the nesting area; mates are independent away from the nest. The ground- nesting (white) species have a complex communal courtship involving a group of males chasing a single female in the air, on land, or in the water while pointing, gaping, and thrusting their bills at each other. They can finish the process in a day. The tree- nesting species have a simpler process in which perched males advertise for females. Colonies of tens or hundreds, rarely thousands, of birds breed regularly on small coastal and subcoastal islands where food is seasonally or permanently available. In arid inland Australia, especially in the endorheic. Lake Eyre basin, pelicans will breed opportunistically in very large numbers of up to 5. The male brings the nesting material, in ground- nesting species (which may not build a nest) sometimes in the pouch, and in tree- nesting species crosswise in the bill. The female then heaps the material up to form a simple structure. Both parents feed their young. Small chicks are fed by regurgitation; after about a week they are able to put their heads into their parent. From about 2. 5 days old. They may remain with their parents afterwards, but are now seldom or never fed. They are mature at three or four years old. Most species' populations are more or less stable, although three are classified by the IUCN as being at risk. All species breed readily in zoos, which is potentially useful for conservation management. With restrictions on DDT use in the US from 1. It declined dramatically during the 1. El Ni. Conservation needs include regular monitoring throughout the range to determine population trends, particularly after El Ni. Numbers declined substantially during the 2. Sittaung valley breeding colony in Burma through deforestation and the loss of feeding sites. In the absence of substantial threats or evidence of declines across its range, its conservation status is assessed as being of Least Concern. Regional threats include the drainage of wetlands and increasing disturbance in southern Africa. The species is susceptible to bioaccumulation of toxins and to the destruction of nesting trees by logging. The overall trend in numbers is uncertain, with a mix of regional populations that are increasing, declining, stable or unknown, but there is no evidence of rapid overall decline and the status of the species is assessed as being of Least Concern. Threats include the drainage of wetlands, persecution and sport hunting, disturbance at the breeding colonies, and contamination by pesticides and heavy metals. The main ongoing threats include hunting, especially in eastern Asia, disturbance, coastal development, collision with overhead power lines and the over- exploitation of fish stocks. However, several colonies are increasing in size and the colony at the Small Prespa Lake in Greece has nearly 1. The species is assessed as being of Least Concern. This has led to suggestions that pelican numbers should be controlled at vulnerable colonies. Human presence alone can cause the birds to accidentally displace or destroy their eggs, leave hatchlings exposed to predators and adverse weather, or even abandon their colonies completely. It entered the oceanic food web, contaminating and accumulating in several species, including one of the pelican. Its metabolite. DDE is a reproductive toxicant in pelicans and many other birds, causing eggshell thinning and weakening, and consequent breeding failure through the eggs being accidentally crushed by brooding birds. Since an effective ban on the use of DDT was implemented in the US in 1. A 2. 00. 7 report to the California Fish and Game Commission estimated that, during the previous 2. Fish hooks are swallowed or catch in the skin of the pouch or webbed feet, and strong monofilament fishing line can become wound around bill, wings or legs, resulting in crippling, starvation, and often death. Local rescue organisations have been established in North America and Australia by volunteers to treat and rehabilitate injured pelicans and other wildlife. Specialist feather lice of the genus Piagetella are found in the pouches of all species of pelican, but are otherwise only known from New World and Antarctic cormorants. Avian malaria is carried by the mosquito. Culex pipens, and high densities of these biting insects may force pelican colonies to be abandoned. Leeches may attach to the vent or sometimes the inside of the pouch.
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