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Dipper


The genus Cinclus was introduced by the German naturalist Moritz Balthasar Borkhausen in 1797 with the white-throated dipper (Cinclus cinclus) as the type species.[2][3] The name cinclus is from the Ancient Greek word kinklos that was used to describe small tail-wagging birds that resided near water.[4]




dipper


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A 2002 molecular phylogenetic study of the dippers looked at the DNA sequences of two mitochondrial genes. It found that the Eurasian white-throated dipper and brown dipper are sister species as are the South American white-capped dipper and rufous-throated dipper. The study also showed that the dipper family, Cinclidae, is most closely related to the thrush family, Turdidae.[1]


Unlike many water birds, dippers are generally similar in form to many terrestrial birds (for example, they do not have webbed feet), but they do have some morphological and physiological adaptations to their aquatic habits. They have evolved solid bones to reduce their buoyancy,[10] and their wings are relatively short but strongly muscled, enabling them to be used as flippers underwater. The plumage is dense with a large preen gland for waterproofing their feathers. Relatively long legs and sharp claws enable them to hold on to rocks in swift water. Their eyes have well-developed focus muscles that can change the curvature of the lens to enhance underwater vision.[11] They have nasal flaps to prevent water entering their nostrils.[12]


Linear breeding territories are established by pairs of dippers along suitable rivers, and maintained against incursion by other dippers. Within their territory the pair must have a good nest site and roost sites, but the main factor affecting the length of the territory is the availability of sufficient food to feed themselves and their broods. Consequently, the length of a territory may vary from about 300 metres (1,000 feet) to over 2,500 metres (8,200 feet).[8]


Dippers are completely dependent on fast-flowing rivers with clear water, accessible food and secure nest-sites. They may be threatened by anything that affects these needs such as water pollution, acidification and turbidity caused by erosion. River regulation through the creation of dams and reservoirs, as well as channelization, can degrade and destroy dipper habitat.[8]


Dippers are also sometimes hunted or otherwise persecuted by humans for various reasons. The Cyprus race of the white-throated dipper is extinct. In the Atlas Mountains dippers are claimed to have aphrodisiacal properties. In parts of Scotland and Germany, until the beginning of the 20th century, bounties were paid for killing dippers because of a misguided perception that they were detrimental to fish stocks through predation on the eggs and fry of salmonids.[8]


Despite threats to local populations, the conservation status of most dipper species is considered to be of least concern. The one exception, the rufous-throated dipper, is classified as vulnerable because of its small, fragmented and declining population which is threatened, especially in Argentina, by changes in river management.[20]


Look for American Dippers on boulders or fallen logs along whitewater streams in western North America. Their characteristic dipping motion helps make them noticeable despite their subdued plumage. You may see dippers flying low to the water upstream or downstream, but rarely any distance away from the river course. Watch out for nests clinging to midstream boulders or under bridges, or for white-splattered rocks in midstream, for evidence dippers are in the area. Their long, burbling song is reminiscent of a Pacific or Winter Wren.


The dipper, North America's only aquatic songbird, is one of only five species of dipper in the world. Formerly known as water "ouzels," dippers are named for their characteristic habit of 'dipping' or bobbing up and down while perched on a rock or ledge. This function is not well understood though some believe the action of dipping may help them spot prey beneath the surface of the water or help conceal their image from predators. Dipping may also be a form of visual communication between birds in the noisy environment they favor, which is a clear, clean, fast-moving stream.


A plain-looking medium-sized bird, the dipper is gray except for the upper eyelid which has tiny white feathers. It has a large head, long legs and short neck and tail. The immature dipper is similar to the adult but has faint pale barring on the underside. Males and females look alike, though the average body mass of males is greater than that of females (57g vs 51g in Southeast Alaska).


Dippers are fiercely territorial, vigorously defending nesting territories from other pairs. They are socially monogamous in most cases and often return to the same nest year after year. The nest is a volleyball-sized shell of moss, with an inner saucer of dry grass and rootlets on which the eggs are laid. In Southeast Alaska, nest building usually begins in April or May though cold weather and high altitudes result in delayed nesting. By contrast, dippers in the Nome area have been noted nesting in July. Nests are customarily placed on cliff ledges or in little caves under boulder piles but dippers will also use old wooden dams and bridges that have horizontal ledges.


Dippers feed principally on aquatic larvae of insects like mayflies, mosquitoes, and caddisflies. They also eat dragonflies, worms, small fish, fish eggs, tadpoles and small shrimp-like crustaceans called amphipods. American dippers can wade, swim and dive from either the water or the air and are able to move rocks on the stream bed to get at food. They take prey from the water's surface while swimming or from mid-air while in flight. They will even use their wings to 'fly' underwater when chasing prey.


The American dipper is considered a species of Least Concern by the International Union of Conservation of Nature and Natural Resources; however, information is lacking on range-wide population trends.


Dippers are indicators of stream quality, because their aquatic prey becomes scarce in polluted streams. Sedimentation, acidifications and toxic wastes from industry of various types can cause reproductive failure and abandonment of stream. In addition, dippers accumulate heavy metals such as cadmium and lead in their bodies, which interfere with enzymes essential to the formation of hemoglobin (the oxygen-carrying molecule in the blood). Using dippers as indicator species requires more than knowledge of water quality, however, because more than one factor may cause population declines.


Dippers were individuals who attempted to hack into needlecast transmissions to download memory fragments to sell on the black market. Ava Elliot was an experienced dipper who got caught and sentenced to thirty years.


Background and purpose: The fluctuation of circadian blood pressure (BP) is of great diversity in patients with essential hypertension and may provide significant prognostic value for stroke. However, it remains uncertain whether reverse-dipper pattern of BP influences the incidence of lacunar infarction in hypertensive patients.


Results: A total of 93 patients (25.7%) had reverse-dipper BP pattern. Non-dipper pattern of BP was observed in 179 hypertensive patients (49.4%) and dipper pattern in 90 patients (24.9%). The percentage of lacunar infarction was the highest in the patients with reverse-dipper pattern compared with pure hypertension or atherothrombotic cerebral infarction (P


Conclusions: Reverse-dipper BP pattern may serve as an independent risk factor for lacunar infarction and more personalized BP management should be offered to the patients who have elevated nocturnal BP.


This dipper is equipped with three kinds of garlic and herbs to bring the fine Italian flavor to your home. Dip your favorite crusty baguette or add to vegetables and meat marinades before grilling or roasting to give your meal rich flavor.


Wanting to be more environmentally responsible, a major US-based chain challenged Server to replace their need for a traditional dipper well sink that used an average of 30-60 gallons of water per hour; keeping bacteria off utensils.


We learned conventional continuous-flow dipper wells use over 250,000 gallons of water every year. However, if utensils are held above 140ºF it keeps them safe from bacteria growth while saving water, energy, and money. 041b061a72


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