68-536: 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
136-465: 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, with Charadrii being repurposed into a monophyletic suborder of plovers, oystercatchers, and their close relatives. The waders are traditionally
204-643: A decline in numbers of around 25% in the previous 15 years. It is also among the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds ( AEWA ) applies. In 2024, L. limosa was listed as Endangered under the Australian EPBC Act . Shorebird Waders or shorebirds are birds of the order Charadriiformes commonly found wading along shorelines and mudflats in order to forage for food crawling or burrowing in
272-575: A godwit numbered 234684 left Alaska on 13 October and flew non-stop to Tasmania, the first time a tagged bird has flown this route. It flew a minimum of 13,560 km (8,430 mi) in 11 days 1 hour: a record non-stop distance. To fuel such long journeys, L. l. baueri birds in New Zealand deposit much more fat for their body size than other subspecies, allowing them to fly 6,000 km (3,728 mi) to 8,600 km (5,344 mi). Both Australasian subspecies head north to their breeding grounds along
340-562: A greatly enlarged order Ciconiiformes . 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 fewer than four charadriiform lineages in
408-530: A group of two Charadriiform suborders which include 13 families . Species in the third Charadriiform suborder, Lari , are not universally considered as waders, though the Larine families which may variously be included are listed below as well. Shorebirds is a blanket term used to refer to multiple bird species 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
476-529: A long upturned bill. Bar-tailed godwits breed on Arctic coasts and tundra from Scandinavia to Alaska , and overwinter on coasts in temperate and tropical regions of Australia and New Zealand. The migration of the subspecies Limosa lapponica baueri across the Pacific Ocean from Alaska to New Zealand is the longest known non-stop flight of any bird, and also the longest journey without pausing to feed by any animal. The round-trip migration for this subspecies
544-406: A major staging site in the northern Yellow Sea , they continue to hunt polychaetes , but most of their food intake is the bivalve mollusc Potamocorbula laevis , which they generally swallow whole. The sexual dimorphism also leads to differences in foraging behaviour which enables more effective exploitation. Male bar-tailed godwits are smaller than females and have shorter bills. In a study at
612-435: A new known flight record of 11,680 km (7,258 mi). This L. l. bauri female made a 174-day round-trip journey of 29,280 km (18,194 mi) with 20 days of flying. In 2021, a male bar-tailed godwit, 4BBRW, set a new record for non-stop migratory flight with an 8,100 mile (approximately 13035 km) flight from Alaska, USA to New South Wales, Australia. The same individual held a previous record in 2020. In 2022,
680-403: 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. 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
748-443: 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 Charadrii displays the widest range of sexual dimorphisms seen in the order Charadriiformes. However, cases of sexual monomorphism, where there are no distinguishing physical features besides external genitalia, are also seen in this order. One of
SECTION 10
#1732884231463816-597: A temporary territory and perform display flights to attract a mate. Several nest scrapes are made away from the courtship territory, and are defended from other godwits. Once eggs are laid, an area of 30–50 m (98–164 ft) around the nest is defended. The nest is a shallow scrape on the ground, usually in short vegetation. The eggs may be hidden with vegetation by the incubating parent. The single brood of three to six eggs, coloured olive-green to dark brown, measure 55 mm × 37 mm (2.2 in × 1.5 in) and weigh 39 g (1.4 oz) each (of which 6%
884-462: A volcanic eruption, complete breeding failures can occur. They mainly eat invertebrates , but also aquatic plants in winter and on migration. In the breeding season, prey includes beetles , flies, grasshoppers , dragonflies , mayflies , caterpillars , annelid worms and molluscs . Occasionally, fish eggs, frogspawn and tadpoles are eaten. In water, the most common feeding method is to probe vigorously, up to 36 times per minute, and often with
952-759: A wader census conducted Bird New Zealand in 1983 and they found that the number of bar-tailed godwits in New Zealand as well has declined over the last 35 years which drops from 101,000 in 1983–1993 to 78,000 in 2005-2019. The decline in numbers of bar-tailed godwits is probably associated with habitat loss and degradation near Yellow Sea. They are quite sensitive and easily spooked so it prevents them from disturbance at high tide roosts which leads to stress since they could not rest. We need to contribute to their conservation measures to help maintain their population by restricting human access, creating protected zones and keeping safe distance from bar-tailed godwits. In 2024, L. l. baueri and menzbieri were listed as Endangered under
1020-422: Is also some regional variation in size (see subspecies, below). The adult has blue-grey legs and a long, tapering, slightly upturned bi-coloured bill: pink at the base and black towards the tip. The neck, breast and belly are unbroken brick red in breeding plumage, and dark brown above. Females breeding plumage is much duller than males, with a chestnut to cinnamon belly. Breeding plumage is not fully apparent until
1088-464: Is around 5% larger than the male, with a bill 12–15% longer. The most common call is a strident weeka weeka weeka . A study of black-tailed godwits in the Netherlands found a mortality rate of 37.6% in the first year of life, 32% in the second year, and 36.9% thereafter. Black-tailed godwits have a discontinuous breeding range stretching from Iceland to the far east of Russia. Their breeding habitat
1156-534: Is comparatively smaller than subspecies baueri . Baueri is known to deposit 75-85g more fat for their size. In general, larger godwits have greater flight costs, which accounts for the difference in travel expenses. The smaller subspecies with would exhibit lower travel cost with and without wind assistance. Baueri subspecies is predicted with travel distance further than taymyrensis ranged from 8,200 to 8,600km with wind assistance, and 6,000 to 6,300km with no wind assistance. Those flight lengths are sufficient to allow
1224-516: Is frequently well concealed by standing vegetation and placed near or between tussocks. The construction of the nest is conducted by both parents which lining is added to the nest during egg laying. The eggs shape are pointed oval to pyriform and subpyriform to ovate pyriform and usually the latter eggs are elongate ovate. Their main source of food in wetlands is bristle-worms (up to 70%), supplemented by small bivalves and crustaceans . In wet pastures, bar-tailed godwits eat invertebrates. In
1292-455: Is from Latin and means "muddy", from limus , "mud", referring to its preferred habitat. The specific name lapponica refers to Lapland . The English term "godwit" was first recorded in about 1416–17 and may be an imitation of the bird's call, or be derived from the Old English "god whit", meaning "good creature", perhaps referring to its eating qualities. Its English name is taken from
1360-406: Is from Latin and means "muddy", from limus , "mud". The English name "godwit" was first recorded in about 1416–17 and is believed to imitate the bird's call. Four subspecies are recognised: The black-tailed godwit is a large wader with long bill (7.5 to 12 cm (3.0 to 4.7 in) long), neck and legs. During the breeding season, the bill has a yellowish or orange-pink base and dark tip;
1428-526: Is most likely limited to male-to-male aggression on the ground and other Limosa species also do not show high level territoriality. Aggressive reaction distance is usually less than 2 m. The bar-tailed godwit does not exhibit the "tumbling flight" that the Black-tailed Godwit shows after its ascending phase, and its limping flight is much more ordered and less chaotic than that of the Black-tailed Godwit. The highly conspicuous limping flight with song in
SECTION 20
#17328842314631496-560: Is mostly are a repetition of basic tonal element of 0.15-0.2s. Some vocalizations have multiple functions and some calls is used in a same context which is commonly shown in other shorebirds. The most common song-flight they have done is the ceremonial flights. ceremonial flights are performed disproportionately by the males and the function is mainly heterosexual. The flight was not found to induce ceremonial flight in neighboring males. There are 4 stages in ceremonial flights: (1) ascent, (2) limping flight, (3) gliding, and (4) descent to attract
1564-458: Is not apparent in their non-breeding grounds in New Zealand; birds of different sizes mix freely. Limosa lapponica is distinguished from the black-tailed godwit ( Limosa limosa ) by its black-and-white horizontally-barred (rather than wholly black) tail, and lack of white wing bars. The most similar species is the Asiatic dowitcher ( Limnodromus semipalmatus ). It was evident for some time that
1632-566: Is over 29,000 km (18,020 mi). The bar-tailed godwit was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Scolopax limosa . It is now placed with three other godwits in the genus Limosa that was introduced by the French zoologist Mathurin Jacques Brisson in 1760. The genus name Limosa
1700-818: Is river valley fens , floods at the edges of large lakes, damp steppes , raised bogs and moorlands . An important proportion of the European population now uses secondary habitats: lowland wet grasslands, coastal grazing marshes , pastures , wet areas near fishponds or sewage works, and saline lagoons. Breeding can also take place in sugar beet , potato and rye fields in the Netherlands and Germany. In spring, black-tailed godwits feed largely in grasslands, moving to muddy estuaries after breeding and for winter. On African wintering grounds, swamps, floods and irrigated paddy fields can attract flocks of birds. In India, inland pools, lakes and marshes are used, and occasionally brackish lakes, tidal creeks and estuaries. Godwits from
1768-468: Is shell). Incubation lasts 22–24 days and is performed by both parents. The young are downy and precocial and are brooded while they are small and at night during colder weather. After hatching, they are led away from the nest and may move to habitats such as sewage farms, lake edges, marshes and mudflats. The chicks fledge after 25–30 days. Black-tailed godwit productivity varies, positively, with spring temperatures. However, during extreme events, such as
1836-571: Is the least sandpiper , small adults of which can weigh as little as 15.5 grams (0.55 oz) and measure just over 13 centimetres (5 inches). The largest species is believed to be the Far Eastern curlew , at about 63 cm (25 in) and 860 grams (1 pound 14 ounces), although the beach thick-knee is the heaviest at about 1 kg (2 lb 3 oz). In the Sibley-Ahlquist taxonomy , waders and many other groups are subsumed into
1904-403: Is the national bird of the Netherlands. The black-tailed godwit was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Scolopax limosa . It is now placed with three other godwits in the genus Limosa that was introduced by the French zoologist Mathurin Jacques Brisson in 1760. The name Limosa
1972-646: Is unclear, potential destinations include the Yellow Sea, China, and Korea (39°45′N, 124°30′E; 9,600 km) from the Gulf of Carpentaria , Australia (17°38′S, 140°06′E; 3,800 km). Waders are known to use mostly fat to fuel their long flights that sometimes undertake 10,000km to 29,000km and also catabolizing lean tissue from their organs. The sexual dimorphism is also thought to contribute to them having different fuel deposition. The typical shorebird fat loads are 35%-40% of their body mass. Juvenile males migrating from South Alaska have
2040-504: 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
2108-462: 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. 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
Black-tailed godwit - Misplaced Pages Continue
2176-481: 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
2244-641: The Icelandic population winter mainly in the United Kingdom, Ireland, France and the Netherlands, though some fly on to Spain, Portugal and perhaps Morocco. Birds of the limosa subspecies from western Europe fly south to Morocco and then on to Senegal and Guinea-Bissau. Birds from the eastern European populations migrate to Tunisia and Algeria, then on to Mali or Chad. Young birds from the European populations stay on in Africa after their first winter and return to Europe at
2312-519: The Manawatū Estuary, shorter-billed birds (males) fed mostly on small surface prey like Potamopyrgus snails, half being snail specialists, whereas females consumed more deeply-buried prey such as worms; the birds also displayed some individual food preferences. They are known to forage actively in the day and night. They will pick items on the surface while walking or probes for items in matted vegetation by inserting and twisting bills. In Europe,
2380-567: The age of two years. Asian black-tailed godwits winter in Australia, Taiwan, the Philippines, Indonesia, and Papua New Guinea. Black-tailed godwits are much more likely to be found on inland wetlands than the more coastal bar-tailed godwit . They migrate in flocks to western Europe, Africa, south Asia and Australia. Although this species occurs in Ireland and Great Britain all year-round, they are not
2448-412: The aggressive behaviour. During courtship, they tend to point their bill slightly upwards along with raising their tails while during aggression, they will point the bill downwards in a normal tail posture. It is common to perform tail-raising in this family. Nest-scraping behaviour is also shown by the ruffling of the back-feathers. Although the immediate destinations and flight lengths of this species
2516-489: The bar-tailed godwit is Near Threatened, and the population is declining. Fewer birds have been using East African estuaries since 1979, and there has been a steady decline in numbers around the Kola Peninsula , Siberia, since 1930. The global population is estimated to number 1,099,000–1,149,000 individuals. Both L. l. bauri and L. l. menzbieri adult survival rates decreased between 2005 and 2012, probably because of
2584-496: The base is pink in winter. The legs are dark grey, brown or black. The sexes are similar, but in breeding plumage, they can be separated by the male's brighter, more extensive orange breast, neck and head. In winter, adult black-tailed godwits have a uniform brown-grey breast and upperparts (in contrast to the bar-tailed godwit 's streaked back). Juveniles have a pale orange wash to the neck and breast. In flight, its bold black and white wings and white rump can be seen readily. When on
2652-489: The biggest factors that leads to the development of sexual dimorphism in shorebirds is sexual selection . 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
2720-601: The black-and-white barred tail and upper tail coverts in this species. In French it is known as barge rousse , Russian maliy veretennik , Inuit chiuchiuchiak , Yup'ik tevatevaaq , and Māori kūaka . Four subspecies are recognised: The bar-tailed godwit is a relatively short-legged species of godwit . The bill-to-tail length is 37–41 cm (15–16 in), with a wingspan of 70–80 cm (28–31 in). Males average smaller than females but with much overlap; males weigh 190–400 g (6.7–14.1 oz), while females weigh 260–630 g (9.2–22.2 oz); there
2788-551: The ceremonial flight is potentially to give signaling value are pivoting take off during ascent, diving and breaking with primaries during descent and wings-high after landing. It is the most highly possible for long-distance signalling to be aimed only to a nearby mate. Another common flight that occurs in this species is the pursuit flight which is initiated by a paired female. The males will follow closely behind. Sometimes, another male can join in if they are not mated yet. The aggressive and courtship behaviour should not be similar as
Black-tailed godwit - Misplaced Pages Continue
2856-603: The coast of Asia northwards and southwards, but those breeding in Alaska migrate directly across the Pacific to Australasia 11,000 km (6,835 mi) away. To track the return journey, seven birds in New Zealand were tagged with surgically implanted transmitters and tracked by satellite to the Yellow Sea in China, a distance of 9,575 km (5,950 mi); the actual track flown by one bird
2924-672: The coast of Asia to the Yalu Jiang coastal wetland in the north Yellow Sea, the most important staging grounds for godwits and great knots ( Calidris tenuirostris) in their northern migration. L. l. baueri birds rested for about 41 days before continuing approximately 7,000 km (4,350 mi) on to Alaska. L. l. menzbieri spent on average 38 days in the Yellow Sea region and flew an additional 4,100 km (2,548 mi) to high Arctic Russia. Birds will often depart early from New Zealand if there are favourable winds; they seem to be able to predict weather patterns that will assist them on
2992-441: The eggs for 20 to 21 days, the male during the day and the female at night. The young fledge when they are around 28 days old. They first breed when aged 2 years. The earliest clutch may start by mid-May on coastal Yukon-Kuskokwim Delta. There are never 2 broods at once but it may replce the first clutch. The nest site is variable in selection where there is a slighly elevated ridge drier than surrounding vegetation. The site
3060-540: The entire migration route. Birds that had nested in southern Alaska were larger and departed New Zealand earliest; this pattern was repeated six months later, with birds departing Alaska in the same order they arrived, and over the same span of days. Birds in southern New Zealand departed on average 9–11 days earlier than birds in more northern sites. Godwits arrive at the Yukon-Kuskokwim Delta in Alaska in two waves; local breeders in early May, and larger flocks in
3128-433: The females tend to feed in deeper water than males. Males that feed in deeper water are less successful than males that feed in the tide line. Meanwhile, females are successful at both locations. Birds that prey in flocks have higher prey capture than birds that prey alone. The individuals also capture fewer prey when there is drop in ambient temperature that slows the activity of prey. The degree of feeding activity depends on
3196-465: The females. There are 3 categories in ceremonial flights: (A) A straight line, (B) performing 1 or more circles, (C) wide circles. The ceremonial flight is also known to be similar to Black-tailed godwit. They lack the flight that corresponds to the tumbling flight and the limping flight is not so erratic as in Black-tailed Godwit. The main purpose of this flight is to announce to the females that they are not mated yet. Their territorial defence behaviour
3264-429: The first part of their migration from New Zealand, and so they are most likely to receive wind assistance to Australia. Sometimes during Southward migration, they will make some stopovers in different staging sites if their destinations are likely to be father north than Australia or Papua New Guinea and Irian Jaya. These massive flights might involve extensive fueling periods before and during migration. This calls for
3332-453: The ground it can be difficult to separate from the similar bar-tailed Godwit, but the black-tailed godwit's longer, straighter bill and longer legs are diagnostic. Black-tailed godwits are similar in body size and shape to bar-taileds, but stand taller. It measures 42 cm (17 in) from bill to tail with a wingspan of 70–82 cm (28–32 in). Males weight around 280 g (9.9 oz) and females 340 g (12 oz). The female
3400-589: The head completely submerged. On land, black-tailed godwits probe into soft ground and also pick prey items from the surface. In Europe, black-tailed godwits are only hunted in France, with the annual total killed estimated at 6,000 to 8,000 birds. This puts additional pressure on the western European population, and the European Commission has a management plan in place for the species in its member states. In England, black-tailed godwits were formerly much prized for
3468-409: The highest fat load, but we cannot conclude that for all godwits migrating from the same breeding ground since juveniles are still growing and have smaller body sizes than adults. The female godwits are found to be the heaviest due to their body size being larger than males, and the fat content was also found to be high, from 197-280g. In the size comparison of the subspecies with taymyrensis which
SECTION 50
#17328842314633536-456: The individuals from northern New Zealand potentially to Japan or South Korea. New Zealand godwits would need to have wind assistance comparable to taymyrensis , the European birds, or the European bird would need to retain significant amounts of fat after migration in order for the greater flight ranges to be feasible. This species is able to "ride" high-pressure systems over the Tasman Sea during
3604-497: The loss of intertidal staging areas in the Yellow Sea. The construction of seawalls and the reclamation of mudflats have led to a critical reduction in food supplies for migrating birds, particularly subspecies like L. l. menzbieri that rely on the Yalu Jiang estuary on both their northward and southward migrations. Numbers of L. l. baueri have declined in New Zealand from over 100,000 in the late 1980s to 67,500 in 2018. Meanwhile,
3672-530: The migrating birds can fly distances up to 5000km non stop. All bar-tailed godwits spend the Northern Hemisphere summer in the Arctic, where they breed, and make a long-distance migration south in winter to more temperate areas. L. l. lapponica make the shortest migration, some only as far as the North Sea , while others travel as far as India. Bar-tailed godwits nesting in Alaska ( L. l. baueri ) travel all
3740-640: The mud and sand, usually small arthropods such as aquatic insects or crustaceans . The term "wader" is used in Europe, while "shorebird" is used in North America, where "wader" may be used instead to refer to long-legged wading birds such as storks and herons . There are about 210 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
3808-477: 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 . The majority of species eat small invertebrates picked out of mud or exposed soil. Different lengths of bills enable different species to feed in
3876-400: The risks of continuing to fly over open oceans when the wind is unfavourable. This migration strategy of Australasian bar-tailed godwits is exemplify by their exceptional travels, which cross hemispheres and encompass 10,000km, and their reliance on a few number of refueling sites. These extreme flights are also dependent on the presence and productivity of these staging sites. The status of
3944-435: 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. This would essentially lead to monomorphism within the species but is subject to change once sexual selection acts on
4012-766: The same birds. The breeding birds depart in autumn, but are replaced in winter by the larger Icelandic race. These birds occasionally appear in the Aleutian Islands and, rarely, on the Atlantic coast of North America. Black-tailed godwits are mostly monogamous ; although it was not recorded in a four-year study of 50–60 pairs, bigamy was considered "probably frequent". A study of the Icelandic population showed that despite spending winter apart, pairs are reunited on their breeding grounds within an average of three days of each other. If one partner does not arrive on time, 'divorce' occurs. They nest in loose colonies. Unpaired males defend
4080-818: 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 . 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. In monogamous species, where male individuals mate with
4148-586: The table. Sir Thomas Browne (1605–1682) said: "[Godwits] were accounted the daintiest dish in England and I think, for the bignesse, of the biggest price." Old names included Blackwit, Whelp, Yarwhelp, Shrieker, Barker and Jadreka Snipe. The Icelandic name for the species is Jaðrakan. There is an estimated global population of between 634,000 and 805,000 birds and estimated range of 7,180,000 square kilometres (2,770,000 sq mi). In 2006 BirdLife International classified this species as Near Threatened due to
SECTION 60
#17328842314634216-493: The third week of May en route to breeding grounds further north. The bar-tailed godwit is a non-breeding migrant in Australia and New Zealand. Birds first depart for their northern hemisphere breeding sites at age 2–4. Breeding take place each year in Scandinavia, northern Asia, and Alaska. The nest is a shallow cup in moss sometimes lined with vegetation. Clutch size is from 2 to 5, averaging four. Both sexes share incubation of
4284-606: The third year, and there are three distinguishable age classes; during their first migration north, immature males are noticeably paler in colour than more mature males. Non-breeding birds seen in the Southern Hemisphere are plain grey-brown with darker feather centres, giving them a striped look, and are whitish underneath. Juveniles are similar to non-breeding adults but more buff overall with streaked plumages on flanks and breast. Alaska-breeding bar-tailed godwits show an increase in body size from north to south, but this trend
4352-598: The tide, weather, season and the behaviour exhibited by the prey. In New Zealand, the female baueri has a probe rate of 26.5 probes per 4 minutes period which is 1.6 times higher than that of males but the feeding success is observed to be similar in both sexes. The tapping technique is seen to be more useful in males than the females. During breeding season, shore birds such as bar-tailed godwit will exhibit conspicuous acts such as song flight, courtship, copulation and antagonistic behaviour. They can produce 9 different vocalizations with increasing and decreasing frequency which
4420-558: 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. Bar-tailed godwit The bar-tailed godwit ( Limosa lapponica ) is a large and strongly migratory wader in the family Scolopacidae , which feeds on bristle-worms and shellfish on coastal mudflats and estuaries . It has distinctive red breeding plumage, long legs, and
4488-509: The utilization of a flight's network of locations. They will rest, moult and refuel themselves for the remaining distance. Baueri are highly conservative in their use of staging sites to refuel and most of them just stopped in one or two countries when migrating northwards. During southwards migration, some of them will stop in a few islands in the Southwest Pacific Ocean. These altered routes are suggested to be adaptive reactions to
4556-511: The way to Australia and New Zealand. They undertake the longest non-stop migrations of any bird, and to fuel they carry the greatest fat loads of any migratory bird so far studied, reducing the size of their digestive organs to do so. L. l. bauri breeds in Alaska and spends the non-breeding season in eastern Australia and New Zealand. L. l. menzbieri breeds in Siberia and migrates to northern and western Australia. Birds breeding in Siberia follow
4624-548: Was 11,026 km (6,851 mi), taking nine days. At least three other bar-tailed godwits also appear to have reached the Yellow Sea after non-stop flights from New Zealand. One specific female of the flock, nicknamed "E7", flew onward from China to Alaska and stayed there for the breeding season. Then in August 2007 she departed on an eight-day non-stop flight from western Alaska to the Piako River near Thames , New Zealand, setting
#462537