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Whiffling
Whiffling is a term used in ornithology to describe the behavior whereby a bird rapidly descends with a zig-zagging, side-slipping motion. Sometimes to whiffle, a bird flies briefly with its body turned upside down but with its neck and head twisted 180 degrees around in a normal position. The aerodynamics which usually give a bird lift during flying are thereby inverted and the bird briefly plummets toward the ground before this is quickly reversed and the bird adopts a normal flying orientation. This erratic motion resembles a falling leaf, and is used to avoid avian predators or may be used by geese (family Anatidae) to avoid a long, slow descent over an area where wildfowling is practised. The behavior is seen in several species including lesser yellowlegs (''Tringa flavipes''), the black-tailed godwit (''Limosa limosa''), the northern lapwing (''Vanellus vanellus''), geese (e.g. pink-footed goose (''Anser brachyrhynchus'')), three species of scoter (''Melanitta''), and o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Flight
Bird flight is the primary mode of locomotion used by most bird species in which birds take off and fly. Flight assists birds with feeding, breeding, avoiding predators, and migrating. Bird flight is one of the most complex forms of locomotion in the animal kingdom. Each facet of this type of motion, including hovering, taking off, and landing, involves many complex movements. As different bird species adapted over millions of years through evolution for specific environments, prey, predators, and other needs, they developed specializations in their wings, and acquired different forms of flight. Various theories exist about how bird flight evolved, including flight from falling or gliding (the ''trees down'' hypothesis), from running or leaping (the ''ground up'' hypothesis), from ''wing-assisted incline running'' or from '' proavis'' (pouncing) behavior. Basic mechanics of bird flight Lift, Drag and Thrust The fundamentals of bird flight are similar to those of aircraft, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snow Geese
The snow goose (''Anser caerulescens'') is a species of goose native to North America. Both white and dark morphs exist, the latter often known as blue goose. Its name derives from the typically white plumage. The species was previously placed in the genus ''Chen'', but is now typically included in the "gray goose" genus ''Anser''. Snow geese breed north of the timberline in Greenland, Canada, Alaska, and the northeastern tip of Siberia, and spend winters in warm parts of North America from southwestern British Columbia through parts of the United States to Mexico. Snow goose populations increased dramatically in the 20th century. Taxonomy In 1750 the English naturalist George Edwards included an illustration and a description of the snow goose in the third volume of his ''A Natural History of Uncommon Birds''. He used the English name "The blue-winged goose". Edwards based his hand-coloured etching on a preserved specimen that had been brought to London from the Hudson Bay ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithology
Ornithology is a branch of zoology that concerns the "methodological study and consequent knowledge of birds with all that relates to them." Several aspects of ornithology differ from related disciplines, due partly to the high visibility and the aesthetic appeal of birds. It has also been an area with a large contribution made by amateurs in terms of time, resources, and financial support. Studies on birds have helped develop key concepts in biology including evolution, behaviour and ecology such as the definition of species, the process of speciation, instinct, learning, ecological niches, guilds, island biogeography, phylogeography, and conservation. While early ornithology was principally concerned with descriptions and distributions of species, ornithologists today seek answers to very specific questions, often using birds as models to test hypotheses or predictions based on theories. Most modern biological theories apply across life forms, and the number of scientists w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slip (aerodynamic)
A slip is an aerodynamic state where an aircraft is moving ''somewhat'' sideways as well as forward relative to the oncoming airflow or relative wind. In other words, for a conventional aircraft, the nose will be pointing in the opposite direction to the bank of the wing(s). The aircraft is not in coordinated flight and therefore is flying inefficiently. Background Flying in a slip is aerodynamically inefficient, since the lift-to-drag ratio is reduced. More drag is at play consuming energy but not producing lift. Inexperienced or inattentive pilots will often enter slips unintentionally during turns by failing to coordinate the aircraft with the rudder. Airplanes can readily enter into a slip climbing out from take-off on a windy day. If left unchecked, climb performance will suffer. This is especially dangerous if there are nearby obstructions under the climb path and the aircraft is underpowered or heavily loaded. A slip can also be a ''piloting maneuver'' where the pilot del ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatidae
The Anatidae are the biological family of water birds that includes ducks, geese, and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica. These birds are adapted for swimming, floating on the water surface, and in some cases diving in at least shallow water. The family contains around 174 species in 43 genera. (The magpie goose is no longer considered to be part of the Anatidae and is now placed in its own family, Anseranatidae.) They are generally herbivorous, and are monogamous breeders. A number of species undertake annual migrations. A few species have been domesticated for agriculture, and many others are hunted for food and recreation. Five species have become extinct since 1600, and many more are threatened with extinction. Description and ecology The ducks, geese, and swans are small- to large-sized birds with a broad and elongated general body plan. Diving species vary from this in being rounder. Extant s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wildfowling
Waterfowl hunting (also called wildfowling or waterfowl shooting in the UK) is the practice of hunting ducks, geese, or other waterfowl for food and sport. Many types of ducks and geese share the same habitat, have overlapping or identical hunting seasons, and are hunted using the same methods. Thus it is possible to take different species of waterfowl in the same outing. Waterfowl can be hunted in crop fields where they feed, or, more frequently, on or near bodies of water such as rivers, lakes, ponds, swamps, sloughs, or oceanic coastlines. History Prehistoric waterfowl hunting Wild waterfowl have been hunted for food, down, and feathers worldwide since prehistoric times. Ducks, geese, and swans appear in European cave paintings from the last Ice Age, and a mural in the Ancient Egyptian tomb of Khnumhotep II ( BCE) shows a man in a hunting blind capturing swimming ducks in a trap. Muscovy ducks were depicted in the art of the Moche culture of ancient Peru by 200 BCE, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lesser Yellowlegs
The lesser yellowlegs (''Tringa flavipes'') is a medium-sized shorebird. It breeds in the boreal forest region of North America. Taxonomy The lesser yellowlegs was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's ''Systema Naturae''. He placed it in the genus '' Scolopax'' and coined the binomial name ''Scolopax flavipes''. Gmelin based his description on the "yellow shanks" seen in the province of New York in autumn that had been described in 1785 by both the English ornithologist John Latham and by the Welsh naturalist Thomas Pennant. The lesser yellowlegs is now placed in the genus ''Tringa'' that was introduced in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his ''Systema Naturae''. The name ''Tringa'' is the New Latin word given to the green sandpiper by the Italian naturalist Ulisse Aldrovandi in 1603 based on Ancient Greek ''trungas'', a thrush-sized, white-rumped, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black-tailed Godwit
The black-tailed godwit (''Limosa limosa'') is a large, long-legged, long-billed shorebird first described by Carl Linnaeus in 1758. It is a member of the godwit genus, ''Limosa''. There are four subspecies, all with orange head, neck and chest in breeding plumage and dull grey-brown winter coloration, and distinctive black and white wingbar at all times. Its breeding range stretches from Iceland through Europe and areas of central Asia. Black-tailed godwits spend (the northern hemisphere) winter in areas as diverse as the Indian subcontinent, Australia, New Zealand, western Europe and west Africa. The species breeds in fens, lake edges, damp meadows, moorlands and bogs and uses estuaries, swamps and floods in (the northern hemisphere) winter; it is more likely to be found inland and on freshwater than the similar bar-tailed godwit. The world population is estimated to be 634,000 to 805,000 birds and is classified as Near Threatened. The black-tailed godwit is the national bird ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Lapwing
The northern lapwing (''Vanellus vanellus''), also known as the peewit or pewit, tuit or tew-it, green plover, or (in Ireland and Britain) pyewipe or just lapwing, is a bird in the lapwing subfamily. It is common through temperate Eurosiberia. Behaviour It is highly migratory over most of its extensive range, wintering further south as far as North Africa, northern India, Nepal, Bhutan and parts of China. It migrates mainly by day, often in large flocks. Lowland breeders in westernmost areas of Europe are resident. It occasionally is a vagrant to North America, especially after storms, as in the Canadian sightings after storms in December 1927 and in January 1966. It is a wader that breeds on cultivated land and other short vegetation habitats. 3–4 eggs are laid in a ground scrape. The nest and young are defended noisily and aggressively against all intruders, up to and including horses and cattle. In winter, it forms huge flocks on open land, particularly arable land a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geese
A goose (plural, : geese) is a bird of any of several waterfowl species in the family (biology), family Anatidae. This group comprises the genera ''Anser (bird), Anser'' (the grey geese and white geese) and ''Branta'' (the black geese). Some other birds, mostly related to the shelducks, have "goose" as part of their names. More distantly related members of the family Anatidae are swans, most of which are larger than true geese, and ducks, which are smaller. The term "goose" may refer to either a male or female bird, but when paired with "gander", refers specifically to a female one (the latter referring to a male). Young birds before fledging are called goslings. The List of collective nouns, collective noun for a group of geese on the ground is a gaggle; when in flight, they are called a skein, a team, or a wedge; when flying close together, they are called a plump. Etymology The word "goose" is a direct descendant of,''*ghans-''. In Germanic languages, the root gave Old E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pink-footed Goose
The pink-footed goose (''Anser brachyrhynchus'') is a goose which breeds in eastern Greenland, Iceland and Svalbard. It is migratory, wintering in northwest Europe, especially Ireland, Great Britain, the Netherlands, and western Denmark. The name is often abbreviated in colloquial usage to "pinkfoot" (plural "pinkfeet"). ''Anser'' is the Latin for "goose", and ''brachyrhynchus'' comes from the ancient Greek ''brachus'' "short" and ''rhunchos'' "bill". It is a medium-sized goose, long, the wingspan , and weighing . It has a short bill, bright pink in the middle with a black base and tip, and pink feet. The body is mid-grey-brown, the head and neck a richer, darker brown, the rump and vent white, and the tail grey with a broad white tip. The upper wing-coverts are of a somewhat similar pale bluish-grey as in the greylag goose, and the flight feathers blackish-grey. The species is most closely related to the bean goose ''Anser fabalis'' (having even been treated as a subspecies of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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