Wader

Waders are birds commonly found along shorelines and mudflats that wade in order to forage for food (such as insects or crustaceans) in the mud or sand. They are called shorebirds in North America, where the term "wader" is used to refer to long-legged wading birds such as storks and herons. Waders are members of the order Charadriiformes, which includes gulls, auks and their allies.

There are about 210[1] species of wader, most of which live in wetland or coastal environments. Many species of Arctic and temperate regions are strongly migratory, but tropical birds are often resident, or move only in response to rainfall patterns. Some of the Arctic species, such as the little stint, are amongst the longest distance migrants, spending the non-breeding season in the southern hemisphere.

Many of the smaller species found in coastal habitats, particularly but not exclusively the calidrids, are often named as "sandpipers", but this term does not have a strict meaning, since the upland sandpiper is a grassland species.

The smallest member of this group is the least sandpiper, small adults of which can weigh as little as 15.5 grams and measure just over 13 cm (5.1 in). The largest species is believed to be the Far Eastern curlew, at about 63 cm (25 in) and 860 grams (1.90 pounds), although the beach thick-knee is the heaviest at about 1 kg (2.2 lb).

In the Sibley-Ahlquist taxonomy, waders and many other groups are subsumed into a greatly enlarged Ciconiiformes order. However, the classification of the Charadriiformes is one of the weakest points of the Sibley-Ahlquist taxonomy, as DNA–DNA hybridization has turned out to be incapable of properly resolving the interrelationships of the group. Formerly, the waders were united in a single suborder Charadrii, but this has turned out to be a "wastebasket taxon", uniting no less than four charadriiform lineages in a paraphyletic assemblage. However, it indicated that the plains wanderer actually belonged into one of them. Following recent studies (Ericson et al., 2003; Paton et al., 2003; Thomas et al., 2004a, b; van Tuinen et al., 2004; Paton & Baker, 2006), the waders may be more accurately subdivided as follows:

In keeping more in line with the traditional grouping, the Thinocori could be included in the Scolopaci, and the Chionidi in the Charadrii. However, the increasing knowledge about the early evolutionary history of modern birds suggests that the assumption of Paton et al. (2003) and Thomas et al. (2004b) of 4 distinct "wader" lineages (= suborders) already being present around the Cretaceous–Paleogene boundary is correct.

Waders
Temporal range: Late Oligocene to recent
Small bird with long legs standing at water's edge
Semipalmated sandpiper (Calidris pusilla)
Scientific classification
Kingdom:
Phylum:
Class:
Order:
Suborders
Roosting waders Roebuck Bay
Waders roosting on the beach at high tide
Waders in flight Roebuck Bay
Waders in flight
Ringedplovjuly2008
Common ringed plover wading on a shore

Characteristics

Shorebirds is a blanket term used to refer to multiple species of birds that live in wet, coastal environments. Because most these species spend much of their time near bodies of water, many have long legs suitable for wading (hence the name ‘Waders’). Some species prefer locations with rocks or mud. Many shorebirds display migratory patterns and often migrate before breeding season. These behaviors explain the long wing lengths observed in species, and can also account for the efficient metabolisms that give the birds energy during long migrations.[2]

The majority of species eat small invertebrates picked out of mud or exposed soil. Different lengths of bills enable different species to feed in the same habitat, particularly on the coast, without direct competition for food. Many waders have sensitive nerve endings at the end of their bills which enable them to detect prey items hidden in mud or soft soil. Some larger species, particularly those adapted to drier habitats will take larger prey including insects and small reptiles.

Sexual dimorphism

Shorebirds, like many other animals, exhibit phenotypic differences between males and females, also known as sexual dimorphism. In shorebirds, various sexual dimorphisms are seen, including, but not limited to, size (e.g. body size, bill size), color, and agility. In polygynous species, where one male individual mates with multiple female partners over his lifetime, dimorphisms tend to be more diverse.[2] In monogamous species, where male individuals mate with a single female partner, males typically do not have distinctive dimorphic characteristics such as colored feathers, but they still tend to be larger in size compared to females. The suborder of Charadrii displays the widest range of sexual dimorphisms seen in the Charadriiformes order.[3] However, cases of sexual monomorphism, where there are no distinguishing physical features besides external genitalia, are also seen in this order.[4]

Sexual selection

One of the biggest factors that leads to the development of sexual dimorphism in shorebirds is sexual selection.[5] Males with ideal characteristics favored by females are more likely to reproduce and pass on their genetic information to their offspring better than the males who lack such characteristics. Mentioned earlier, male shorebirds are typically larger in size compared to their female counterparts. Competition between males tends to lead to sexual selection toward larger males and as a result, an increase in dimorphism. Bigger males tend to have greater access (and appeal) to female mates because their larger size aids them in defeating other competitors.[5] Likewise, if the species exhibits gender role reversal (where males take on roles traditionally done by females such as childcare and feeding), then males will select female mates based on traits that are the most appealing. In the Jacana species, females compete with each other for access to male mates, so females are larger in size. Males choose female mates based on who presents herself as the strongest and who 'owns' the most territory.[4]

Natural selection

Another factor that leads to the development of dimorphisms in species is natural selection. Natural selection focuses on traits and the environment's response to the traits in question; if the said trait increases the overall fitness of the individual possessing it, then it will be 'selected' and eventually become a permanent part of the population's gene pool. For example, depending on the food available in a shorebird specie's respective niche, bigger bill sizes may be favored in all individuals.[5] This would essentially lead to monomorphism within the species but is subject to change once sexual selection acts on the trait. Sexual selection could give rise to males with relatively larger bills than females if males used their bills to compete with other males. If larger bill size assisted the male in gathering resources, it would also make him more attractive to female mates.[2]

See also

References

  1. ^ G.C. Boere, C.A. Galbraith and D.A. Stroud (2006). "Waterbirds around the world" (PDF). Joint Nature Conservation Committee.
  2. ^ a b c "Explore the World With Shorebirds." U.S. Fish and Wildlife Service, 1 Aug. 2004. Web.<http://www.fws.gov/alaska/external/education/pdf/Chap4.pdf>.
  3. ^ Székely, Tamás, John D. Reynolds, and Jordi Figuerola. 2000. Sexual Size Dimorphism In Shorebirds, Gulls, And Alcids: The Influence Of Sexual And Natural Selection. 54(4): 1404-413. [1]
  4. ^ a b Lindenfors, P., T. Szekely, and J. D. Reynolds. "Directional Changes in Sexual Size Dimorphism in Shorebirds, Gulls and Alcids." Journal of Evolutionary Biology J. Evolution Biol: 930-38. Print.
  5. ^ a b c Szekely, T., R. P. Freckleton, and J. D. Reynolds. "Sexual Selection Explains Rensch's Rule of Size Dimorphism in Shorebirds." Proceedings of the National Academy of Sciences (2004): 12224-2227. Print.

Sources

  • Ericson, P. G. P.; Envall, I.; Irestedt, M.; & Norman, J. A. (2003). Inter-familial relationships of the shorebirds (Aves: Charadriiformes) based on nuclear DNA sequence data. BMC Evol. Biol. 3: 16. doi:10.1186/1471-2148-3-16 PDF fulltext
  • Paton, Tara A.; & Baker, Allan J. (2006). Sequences from 14 mitochondrial genes provide a well-supported phylogeny of the Charadriiform birds congruent with the nuclear RAG-1 tree. Molecular Phylogenetics and Evolution 39(3): 657–667. doi:10.1016/j.ympev.2006.01.011 PMID 16531074 (HTML abstract)
  • Paton, T. A.; Baker, A. J.; Groth, J. G.; & Barrowclough, G. F. (2003). RAG-1 sequences resolve phylogenetic relationships within charadriiform birds. Molecular Phylogenetics and Evolution 29: 268-278. doi:10.1016/S1055-7903(03)00098-8 PMID 13678682 (HTML abstract)
  • Thomas, Gavin H.; Wills, Matthew A. & Székely, Tamás (2004a). Phylogeny of shorebirds, gulls, and alcids (Aves: Charadrii) from the cytochrome-b gene: parsimony, Bayesian inference, minimum evolution, and quartet puzzling. Molecular Phylogenetics and Evolution 30(3): 516-526. doi:10.1016/S1055-7903(03)00222-7 (HTML abstract)
  • Thomas, Gavin H.; Wills, Matthew A.; & Székely, Tamás (2004b). A supertree approach to shorebird phylogeny. BMC Evol. Biol. 4: 28. doi:10.1186/1471-2148-4-28 PMID 15329156 PDF fulltext Supplementary Material
  • van Tuinen, Marcel; Waterhouse, David; & Dyke, Gareth J. (2004). Avian molecular systematics on the rebound: a fresh look at modern shorebird phylogenetic relationships. Journal of Avian Biology 35(3): 191-194. PDF fulltext
  • Explore the World With Shorebirds. (2004). U.S. Fish and Wildlife Service. Web. http://digitalmedia.fws.gov/cdm/ref/collection/document/id/1598
  • Lindenfors, P.; Szekely, T.; and Reynolds, J. D. (2003). Directional Changes in Sexual Size Dimorphism in Shorebirds, Gulls and Alcids. Journal of Evolutionary Biology J Evolution Biol: 930-38. Print.
  • Szekely, T.; Freckleton, R.; & Reynolds, J. (2004). Sexual selection explains Rensch's rule of size dimorphism in shorebirds. Proceedings of the National Academy of Sciences. 101(33): 12224-12227.
  • Szekely, Tamas; John D. Reynolds; and Jordi Figuerola. (2000) Sexual Size Dimorphism in Shorebirds, Gulls, and Alcids: The Influence of Sexual and Natural Selection. Evolution 54(4): 1404-413.

External links

Curlew sandpiper

The curlew sandpiper (Calidris ferruginea) is a small wader that breeds on the tundra of Arctic Siberia. The genus name is from Ancient Greek kalidris or skalidris, a term used by Aristotle for some grey-coloured waterside birds. The specific ferruginea is from Latin ferrugo, ferruginis, "iron rust" referring to its colour in breeding plumage.It is strongly migratory, wintering mainly in Africa, but also in south and southeast Asia and in Australia and New Zealand. It is a vagrant to North America.

Darth Vader

Darth Vader is a fictional character in the Star Wars franchise. He is a primary antagonist in the original trilogy, but, as Anakin Skywalker, is the main protagonist of the prequel trilogy. Star Wars creator George Lucas has collectively referred to the first six episodic films of the franchise as "the tragedy of Darth Vader."Originally a Jedi prophesied to bring balance to the Force, Anakin Skywalker is lured to the dark side of the Force by Palpatine, who is secretly a Sith Lord. After fighting a lightsaber battle with his former mentor Obi-Wan Kenobi in which he is dismembered, Vader is transformed into a cyborg. He then serves the Galactic Empire as Darth Vader until he redeems himself by saving his son, Luke Skywalker, from Palpatine, sacrificing his own life in the process. He is also the father of Princess Leia, the secret husband of Padmé Amidala, and grandfather of Kylo Ren, the main villain of the Star Wars sequel trilogy.

The character has been portrayed by numerous actors. His cinematic appearances span the first six Star Wars films, as well as Rogue One, and he is referenced in both The Force Awakens and The Last Jedi. He also appears in television series (most substantially The Clone Wars) and numerous iterations of the Star Wars Expanded Universe, including video games, novels, and comic books.

Darth Vader has become one of the most iconic villains in popular culture, and has been listed among the greatest villains and fictional characters ever. The American Film Institute listed him as the third greatest movie villain in cinema history on 100 Years... 100 Heroes and Villains, behind Hannibal Lecter and Norman Bates. His role as a tragic hero in the prequel trilogy was met with positive reviews.

Eurasian stone-curlew

The Eurasian stone curlew, Eurasian thick-knee, or simply stone-curlew (Burhinus oedicnemus) is a northern species of the Burhinidae (stone-curlew) bird family.

It is a fairly large wader though is mid-sized by the standards of its family. Length ranges from 38 to 46 cm (15 to 18 in), wingspan from 76 to 88 cm (30 to 35 in) and weight from 290 to 535 g (10.2 to 18.9 oz). with a strong yellow and black beak, large yellow eyes (which give it a "reptilian", or "goggle-eyed" appearance), and cryptic plumage. The bird is striking in flight, with black and white wing markings.

Despite being classed as a wader, this species prefers dry open habitats with some bare ground. It is largely nocturnal, particularly when singing its loud wailing songs, which are reminiscent of that of curlews. Food consists of insects and other small invertebrates, and occasionally small reptiles, frogs and rodents. It lays 2–3 eggs in a narrow scrape in the ground.

The Eurasian stone curlew occurs throughout Europe, north Africa and southwestern Asia. It is a summer migrant in the more temperate European and Asian parts of its range, wintering in Africa.

Great stone-curlew

The great stone-curlew or great thick-knee (Esacus recurvirostris) is a large wader which is a resident breeder in tropical southern Asia from India, Pakistan, Sri Lanka, Bangladesh into South-east Asia.

This species prefers gravel banks along rivers or large lakes, and also beaches. A single egg is laid in a bare scrape on the open shingle.

It is mainly nocturnal or crepuscular like other stone-curlews, but can frequently be seen foraging during the day, moving slowly and deliberately, with occasional short runs. It tends to be wary and flies off into the distance ahead of the observer, employing powerful, rather stiff wingbeats.

The great thick-knee is a large wader at 49–55 cm, and has a massive 7 cm bill with the lower mandible with a sharp angle giving it an upturned appearance. It has unstreaked grey-brown upperparts and breast, with rest of the underparts whitish. The face has a striking black and white pattern, and the bill is black with a yellow base. The eyes are bright yellow and the legs a duller greenish-yellow.

In flight, the great thick-knee shows black and white flight feathers on the upperwing, and a mainly white underwing. Sexes are similar, but young birds are slightly paler than adults.

The call is a wailing whistle, given mainly at night, as with other birds in this family. The great thick-knee eats crabs, large insects, and other animal prey.

Greater sand plover

The greater sand plover (Charadrius leschenaultii) is a small wader in the plover family of birds. The spelling is commonly given as "greater sandplover" or "greater sand-plover", but the official British Ornithologists' Union spelling is "Greater Sand Plover". The genus name Charadrius is a Late Latin word for a yellowish bird mentioned in the fourth-century Vulgate. It derives from Ancient Greek kharadrios a bird found in ravines and river valleys (kharadra, "ravine"). The specific leschenaultii commemorates the French botanist Jean Baptiste Leschenault de la Tour.

Green sandpiper

The green sandpiper (Tringa ochropus) is a small wader (shorebird) of the Old World. The genus name Tringa is the New Latin name given to the green sandpiper by Aldrovandus in 1599 based on Ancient Greek trungas, a thrush-sized, white-rumped, tail-bobbing wading bird mentioned by Aristotle. The specific ochropus is from Ancient Greek okhros, "ochre", and pous, "foot".The green sandpiper represents an ancient lineage of the genus Tringa; its only close living relative is the solitary sandpiper (T. solitaria). They both have brown wings with little light dots and a delicate but contrasting neck and chest pattern. In addition, both species nest in trees, unlike most other scolopacids.Given its basal position in Tringa, it is fairly unsurprising that suspected cases of hybridisation between this species and the common sandpiper (A. hypoleucos) of the sister genus Actitis have been reported.

Hannes Wader

Hannes Wader (born Hans Eckard Wader on 23 June 1942) is a German singer-songwriter ("Liedermacher"). He has been an important figure in German leftist circles since the 1970s, with his songs covering such themes as socialist and communist resistance to oppression in Europe and other places like Latin America. He both wrote new songs and played versions of older historical works.

Hip boot

Hip boots, or hip waders as they are sometimes called, are a type of tall boot initially designed to be worn by river fishermen. Hip boots are typically made out of rubber, and completely cover the legs, up to the tops of the thighs or all the way up to the waist. Hip boots are designed to protect the fisherman from water, and allow wading out into deeper waters in hopes of getting a bigger catch. They also help to keep the feet and legs warm in autumn and winter. Hip boots are also worn by many ecologists and environmental scientists who do tests in swamps or lakes to determine the quality of water.

Hip boots are necessary footwear during flooding, and can be a part of everyday city raingear in order to protect from heavy showers (currently most popular in Japan and Russia as female footwear, usually worn with jeans and raincoat).

Hog Island (Tasmania)

Hog Island is a small island and nature reserve, with an area of 0.35 hectares (0.86 acres), part of the Sloping Island Group, lying in the Frederick Henry Bay, close to the south-eastern coast of Tasmania, Australia. The island is situated around the Tasman and Forestier Peninsulas.Recorded breeding seabird and wader species are Pacific gull, kelp gull, sooty oystercatcher and Caspian tern.

Magellanic plover

The Magellanic plover (Pluvianellus socialis) is a rare and unique wader found only in southernmost South America. It was long placed in with the other plovers in the family Charadriidae; however, behavioural evidence suggested they were distinct, and molecular studies confirmed this, suggesting that they are actually more closely related to the sheathbills, a uniquely Antarctic family. As such it is now placed in its own family, Pluvianellidae. This species is not a long-distance migrant, although some birds move further north in southern Argentina in winter. The species breeds inland and then moves to the coast during the winter, particularly to estuaries.This species is in its structure and habits much like a turnstone, but it cannot be confused with any other wader species. Its upperparts and breast are pale grey, and the rest of the underparts are white. It has short red legs, a black bill and red eyes. In young birds, the eyes and legs are yellowish in colour, and the plumage is grey overall with scaling. The call is a dovelike coo.

This species breeds near water, usually saline lakes but there are reports of nests near rivers as well. Pairs defend territories, and both parents share incubation duties. It lays two large eggs on the ground, although usually only one chick survives. One unique aspect of its behaviour and physiology is its method of feeding its chicks. Chicks are fed by regurgitating food stored in the crop, this species being the only wader to do so.Magellanic plovers feed on small invertebrates, picked from the ground, or from under pebbles, again like a turnstone. They have been observed collecting worms in the bill in a similar fashion to a puffin.

Marsh sandpiper

The marsh sandpiper (Tringa stagnatilis) is a small wader. It is a rather small shank, and breeds in open grassy steppe and taiga wetlands from easternmost Europe to central Asia. The genus name Tringa is the New Latin name given to the green sandpiper by Aldrovandus in 1599 based on Ancient Greek trungas, a thrush-sized, white-rumped, tail-bobbing wading bird mentioned by Aristotle. The specific stagnatilis is from Latin stagnum, "swamp".

Ralph de Gael

Ralph de Gaël (otherwise Ralph de Guader, Radulf Waders or Ralph Wader) (before 1042 – c. 1096) was the Earl of East Anglia (Norfolk and Suffolk) and Lord of Gaël and Montfort (Seigneur de Gaël et Montfort). He was the leading figure in the Revolt of the Earls, the last serious revolt against William the Conqueror.

Recurvirostridae

The Recurvirostridae are a family of birds in the wader suborder Charadrii. It contains two distinct groups of birds, the avocets (one genus) and the stilts (two genera).

Red-necked phalarope

The red-necked phalarope (Phalaropus lobatus) is a small wader.

This phalarope breeds in the Arctic regions of North America and Eurasia. It is migratory, and, unusually for a wader, winters at sea on tropical oceans.

Red phalarope

The red phalarope (called grey phalarope in Europe), Phalaropus fulicarius, is a small wader. This phalarope breeds in the Arctic regions of North America and Eurasia. It is migratory, and, unusually for a wader, migrating mainly on oceanic routes and wintering at sea on tropical oceans.

Snowy plover

The snowy plover (Charadrius nivosus) is a small wader in the plover bird family. It breeds in Ecuador, Peru, Chile, the southern and western United States and the Caribbean. Long considered to be a subspecies of the Kentish plover, it is now known to be a distinct species.

Spotted redshank

The spotted redshank (Tringa erythropus) is a wader (shorebird) in the large bird family Scolopacidae. The genus name Tringa is the New Latin name given to the green sandpiper by Aldrovandus in 1599 based on Ancient Greek trungas, a thrush-sized, white-rumped, tail-bobbing wading bird mentioned by Aristotle. The specific erythropus is from Ancient Greek eruthros, "red", and pous, "foot".It breeds across northern Scandinavia and northern Asia and migrates south to the Mediterranean, the southern British Isles, France, tropical Africa, and tropical Asia for the winter. It is an occasional vagrant to Australia and North America.

Waders (footwear)

Waders denotes a waterproof boot extending from the foot to the chest or neck. They are traditionally made from vulcanised rubber, but available in more modern PVC, neoprene and Gore-Tex variants. Waders are generally distinguished from counterpart waterproof boots by shaft height; the hip boot extending to the thigh and the Wellington boot to the knee. For the sake of emphasis, therefore, waders are sometimes defined by the extent of their coverage as chest waders or as full-body waders. As a drysuit variant, full-body waders come with leaktight cuffs or gloves fitted to the sleeves and with a leaktight collar or hood fitted to the neck, enabling the wearer to remain dry when standing or walking in deeper water. Waders are available with boots attached or can have attached stocking feet (usually made of the wader material), to wear inside boots, or inside swimfins in the case of float tube fishing.

Whimbrel

The whimbrel (Numenius phaeopus) is a wader in the large family Scolopacidae. It is one of the most widespread of the curlews, breeding across much of subarctic North America, Asia and Europe as far south as Scotland.

The whimbrel is a migratory bird wintering on coasts in Africa, southern North America, South America, and South Asia into Australasia. It is also a coastal bird during migration. It is fairly gregarious outside the breeding season.

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