- adult males stand about 105cm tall and weigh up to 18kg
- females are smaller - about 75cm tall and about 4.5kg
- gold and black barred upperparts
- white underparts
- pale grey head, neck and breast
- no hind toe
- no preen gland
- distinctive pinkish coloured down feathers
Male bustards first breed at 5–6 years of age, though they can start showing breeding behaviours, such as displaying, sooner. Females first breed at 2–3 years old. Males moult into their breeding plumage in January, and begin displaying in April. One male may mate several females attracted by his displays, but has no further part in chick-rearing.Females nest on the ground, in a simple scrape - 2–3 eggs are laid from April to May, or into June in more northern regions.Eggs are about 80mm long, smooth, glossy and vary in colour, but are typically olive browns or greens. Eggs are incubated for about 25 days. Chicks fledge at 30–35 days, but remain dependent on the female until they reach full size at about 80–120 days.
Western populations are largely resident, but frequently disperse in winter to find suitable food sources. Eastern populations are fully migratory.
Habitat and Ecology
The great bustard has a very wide range, broken into smaller populations. Strongholds for the species are in Spain and Portugal (about 14,000–14,500 birds), Hungary (1,000–1,200) and Russia (10,000–11,000). Smaller populations occur in northern Morocco, Turkey, southern Ukraine and Germany, with remnant populations elsewhere in eastern Europe.It also occurs across central and eastern Asia, through Kazakhstan and Krgyzstan, and wintering from Syria through southern Azerbaijan and nothern Iran to Uzbekistan and Tadjikistan.
Former European distribution
The great bustard has recently become extinct in Poland, Bulgaria and former Yugoslavia. It became extinct during the 1800s in France (it was last bred 1863) and also in Sweden and Greece
Former British distribution
The bird became extinct in Britain in the late 1830s.Its last confirmed breeding in England was in 1832, and the last known bird was seen in 1838.It was formerly widespread in the UK - from southern England to southern Scotland - and was strongly associated with the chalk downs of Wiltshire, Dorset, Sussex and Kent, and the Wolds of Lincolnshire and Yorkshire.
The Great bustard requires large expanses of open, flat or rolling grassland and is strongly associated with meadows, pastures and stubbles in regions of low intensity agriculture. In Spain, it sometimes uses open woodland, such as olive groves.
It lives mainly on plant material and invertebrates, especially beetles (Coleoptera), crickets and grasshoppers (Orthoptera). Sometimes it eats small vertebrates, such as amphibians or nestling birds.
Life History and Behavior
Great bustards are the most social of the bustards. They are commonly found in small, loose flocks called droves, made up of birds of the same sex and age.
Male great bustards are renowned for their spectacular mating display. They are normally well-camouflaged, so males display to advertise their presence and show off their quality to prospective mates.During his display, a male:
- inflates a special air sac in his neck into a huge balloon, revealing strips of bare skin either side of his neck
- as he expands, he tilts forwards and pulls his head in so that the long whiskery chin feathers point upwards
- he cocks his tail flat along his back, exposing the normally hidden bright white plumage
- then he lowers his wings, with the primary flight feathers folded but with the white secondaries fanning out
- once in full display, he may hold the pose for many minutes, occasionally shifting his feet and shaking his body to emphasise his spectacular appearance
Lifespan, longevity, and ageing
Molecular Biology and Genetics
Barcode data: Otis tarda
There is 1 barcode sequence available from BOLD and GenBank. Below is the sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species. See the BOLD taxonomy browser for more complete information about this specimen. Other sequences that do not yet meet barcode criteria may also be available.
-- end --
Download FASTA File
Statistics of barcoding coverage: Otis tarda
Public Records: 2
Specimens with Barcodes: 2
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
Status in Egypt
The great bustard is classed by the International Union for Conservation of Nature (IUCN) as globally vulnerable, due to rapid population declines across most of its range.The global population is estimated as 45,000, occupying a breeding range of approximately 2.35 million km2.
Great bustard conservation is a major challenge, as its requirement for large land areas managed at low intensity conflicts with modern economic agricultural priorities. However, in the long term, populations will only survive if such low intensity expanses are maintained.This might be achieved in east Asia as new protected areas are established, and in Europe through EU agricultural policies that encourage zoning.
Reintroduction in the UK
A unique conservation attempt is underway in southern England to reintroduce the great bustard into part of its former range.Since 2004, the Great Bustard Group has been carefully releasing young bustards onto Salisbury Plain, Wiltshire, with the aim of establishing a self-sustaining population of great bustards in part of their former UK heartlands.The young birds are imported from the Saratov region of Russia, where they are hand-reared at a field station from eggs salvaged from nests otherwise destroyed by agriculture.The released young bustards formed droves quite early on, but the birds needed to mature before successful breeding could occur. Progress is slow, but steady:
- males were seen displaying in 2007
- females nested in 2007 and 2008, but as the males weren’t fully mature, the eggs were infertile
- in 2009, 2 females successfully hatched 3 chicks, each eventually fledging one
- 4 chicks were hatched in 2010
Great bustards are especially threatened by habitat loss and fragmentation, due to spreading agricultural intensification. There is concern that land privatisation in eastern Europe may accelerate rates of intensification in core population areas.The bird’s habitat is disappearing due to:
- ploughing grasslands
- intensive grazing
- irrigation development
- installation of roads, power-lines, fencing and ditches
- increased mechanisation
- use of chemical fertilisers and pesticides
CITES Appendix I and II, CMS Appendix I and II and CMS MoU in place since 2002. EU Wild Birds Directive Annex I, Bern Convention Annex II, Bonn Convention Annex I (S. Nagy in litt. 1999, 2007, P. Goriup in litt. 2007). A European action plan was published in 1996 and updated in 2009 (Nagy 2009) and an action plan for east Asian populations in 1998. Agri-environmental and land management programmes have been (successfully) implemented in Spain, Portugal, Austria, Hungary, Germany, Serbia. Artificial incubation and chick rearing projects have been established in Germany and Hungary since the 1970s. A UK reintroduction project began in 2003 with chicks imported from the Russian Federation (Dawes 2008). A LIFE Nature project for the species was implemented in Hungary during 2004-2008 with the aim of increasing in-situ protection of the species (Bankovics and LÃ³rÃ¡nt 2008). Other LIFE projects for the species have been implemented in Spain, Portugal, Germany, Austria and Slovakia. Conservation Actions Proposed
Conduct nationwide surveys in countries with currently low quality estimates, to confirm worldwide numbers and trends. Research limiting factors. Research wintering distribution in Russia, Ukraine and Asia. Protect and manage breeding and wintering areas. Upgrade existing and establish new protected areas in east Asia. Implement agri-environment measures for low-intensity farming. Prevent steppe fires, illegal hunting and collision with power-lines. Raise public awareness.
The Great Bustard (Otis tarda) is in the bustard family, the only member of the genus Otis. It breeds in southern and central Europe, where it is the largest species of bird, and across temperate Asia. European populations are mainly resident, but Asian birds move further south in winter. Portugal and Spain now contain about 60% of the world's population.
Taxonomy and etymology
The Great Bustard was classified with its scientific name in 1758 by Carl Linnaeus, though the species was referred to as avis tarda in the much older writings of Pliny the Elder. Otis is an Old Greek name for "bustard". The specific name, tarda, has been traced to an Old Spanish name for "tread", although it has also been used in Latin for "slow" and "deliberate", which is apt to describe the typical walking style of the species.
The male of this huge bird is possibly the heaviest living flying animal. It also arguably the most sexual dimorphic extant bird species, in terms of the size difference between males and females. Among both bustards and all living birds, the mass of this species is rivalled by that of the Kori Bustard, which, due to its relatively longer tarsi and tail, is both longer and taller on average and is less sexually dimorphic. A male is typically 90–105 cm (2 ft 11 in–3 ft 5 in) tall, with a length of around 115 cm (3 ft 9 in) and has a 2.1–2.7 m (6 ft 11 in–8 ft 10 in) wingspan. The male can range in weight from 5.8 to 18 kg (13 to 40 lb), with an average of 9.65 to 13.5 kg (21.3 to 29.8 lb). The heaviest verified specimen, collected in Manchuria, was about 21 kg (46 lb). In a study in Spain, another giant male tipped the scales at 19 kg (42 lb). Larger specimens have been reported but remain unverified.
The female is about a third smaller in linear dimensions, typically measuring 75 to 85 cm (2 ft 6 in to 2 ft 9 in) in height, about 90 cm (2 ft 11 in) in length and 180 cm (5 ft 11 in) across the wings. At an average of 4.4 kg (9.7 lb), the females are roughly one-third the weight of the male. Overall, the female's weight can range from 3.3 to 8 kg (7.3 to 17.6 lb). Perhaps because of this physical sexual dimorphism, there is a skewed sex ratio of about 1.5:1 female to male.
An adult male is brown above, barred with blackish colouration, and white below, with a long grey neck and head. His breast and lower neck sides are chestnut and there is a golden wash to the back and the extent of these bright colours tending to increase as the male ages. In the breeding season, the male has long white neck bristles, which measure up to 12–15 cm (4.7–5.9 in) in length, continually growing from the third to the sixth year of life. In flight, the long wings are predominantly white with brown showing along the edges of the lower primary and secondary feathers and a dark brown streak along the upper-edge of the wing. The breast and neck of the female are buff, with brown and pale colouration over the rest of the plumage rendering it well camouflaged in open habitats. Immature birds resemble the female. The Eastern subspecies (O. t. dybowskii) is more extensively grey in colour in both sexes, with more extensive barring on the back. The Great Bustard has long legs, a long neck and a heavy, barrel-chested body. It is fairly typical of the family in its overall shape and habitat preferences. Three other bustard species overlap in range with this species: the Macqueen's, Houbara and Little Bustards. However, none of these attain the huge sizes, bulky form and plumage coloration of this species. Thus, the Great Bustard is essentially unmistakable.
Among standard measurements in the Eastern race, males have a wing chord length of 59.5 to 63.5 cm (23.4 to 25.0 in), a tail of 21 to 23.5 cm (8.3 to 9.3 in), a tarsus of 14.2 to 15 cm (5.6 to 5.9 in) and an exposed culmen of 4.1 to 4.7 cm (1.6 to 1.9 in). In comparison, the Eastern female measures 45.5 to 49.5 cm (17.9 to 19.5 in) across the wing chord, has a tail of 17.8 to 21 cm (7.0 to 8.3 in), a tarsus of 11.3 to 12.6 cm (4.4 to 5.0 in) and a culmen of 3.5 to 4 cm (1.4 to 1.6 in), respectively. Standard measurements indicate the nominate subspecies is slightly larger than the Eastern subspecies, in adult males, culmen length is to 9.8 cm (3.9 in), wing chord length to 69 cm (27 in), tail length to 29.5 cm (11.6 in) and tarsal length to 22 cm (8.7 in).
This bird's habitat is grassland or steppe defined by open, flat or somewhat rolling landscapes. It can be found on undisturbed cultivation and seems to prefer areas with wild or cultivated crops such as cereals, vineyards and fodder plants. However, during the breeding season, they actively avoid areas with regular human activity and can be distributed by agricultural practices. Great Bustards are often attracted to areas with considerable insect activity.
This species is gregarious, especially in winter when gatherings of several dozen birds may occur. Male and female groups do not mix outside of the breeding season. The Great Bustard has a stately slow walk but tends to run when disturbed rather than fly. Running speeds have not been measured but adult females have been known to outrun red foxes, which can reach a trotting speed of 48 km/h (30 mph). However, they can be fairly strong fliers as well, especially during seasonal movements, and can reach speeds of up to 80 km/h (50 mph) in flight. Both sexes are usually silent but can engage in deep grunts when alarmed or angered. The displaying adult male may produce some booming, grunting and raucous noises. The female may utter some guttural calls at the nest and brooded young make a soft, trilling call in communication with their mothers. The Asian and Russian populations of the species are migratory and will gather in large numbers at pre-migratory sites in order to move collectively to winter grounds. In the remainder of the range, such as Central Asia, only partial migrations may occur based on seasonal food availability. In the Iberian Peninsula, bustards that engage in migration seem to choose different periods for movements based on sex. No population is known to use the same grounds for wintering and summering.
The Great Bustard breeds in March, and a single male may mate with up to five females. Before mating, the males moult into their breeding plumage around January. Males establish dominance in their groups during winter, clashing violently by ramming into and hitting each other with their bills. Like other bustards, the male Great Bustard displays and competes for the attention of females on what is known as a lek. In this species, the male has a flamboyant display beginning with the strutting male puffing up his throat to the size of a football. He then tilts forwards and pulls his head in so that the long whiskery chin feathers point upwards and the head is no longer visible. He next cocks his tail flat along his back, exposing the normally hidden bright white plumage then he lowers his wings, with the primary flight feathers folded but with the white secondaries fanning out. The displaying males, who may walk around for several minutes at a time with feathers flared and head buried, has been described as a "foam-bath" due to its appearance. All breeding Great Bustards also moult again from June to September.
One to three olive or tan coloured, glossy eggs (two eggs being the average) are laid by the female in May or June. The nests, which are shallow scrapes made by the female on dry, soft slopes and plains, are usually situated close to the prior lek location. Nests are situated in sparse clusters, with a study in Inner Mongolia finding nests at a minimal 9 m (30 ft) apart from each other. In the same study, nests were placed at mid-elevation on a hill, at about 190 to 230 m (620 to 750 ft). Nesting sites are typically in dense grassy vegetation about 15 to 35 cm (5.9 to 13.8 in), likely for protection against predation, with extensive exposure to sunlight. Eggs weigh about 150 g (5.3 oz) and are on average 79.4 mm (3.13 in) tall by 56.8 mm (2.24 in) wide. The female incubates the eggs alone for 21 to 28 days. The chicks almost immediately leave the nest after they hatch, although they do not move very far from their mother until they are at least 1 year old. Young Great Bustards begin developing their adult plumage at about 2 months, and begin to develop flying skills at the same time. They practice by stretching, running, flapping, and making small hops and jumps to get airborne. By three months they are able to fly reasonable distances. If threatened, the young stand still, using their downy plumage, mainly sepia in colour with paler buffy streaks, as camouflage. Juveniles are independent by their first winter, but normally stay with their mother until the next breeding season. Males usually start to mate from 5 to 6 years of age, although may engage in breeding display behaviour at a younger age. Females usually first breed at 2 to 3 years old.
This species is omnivorous taking different foods in differing seasons. In northwestern Spain in August, 48.4% of the diet of adult birds was comprised by green plant material, 40.9% was invertebrates and 10.6% was seeds. In the same population during winter, seeds and green plant material compromised almost the entirety of the diet. Alfalfa is seemingly preferred in the diet of birds from Spain. Other favoured plant life in the diet can including legumes, crucifers, common dandelion and grapes and the dry seeds of wheat and barley. Among animal prey, insects are generally eaten and are the main food for young bustards in their first summer, though they then switch to the seasonal herbivorous preferences of adults by winter. Coleoptera (including beetles), Hymenoptera (including bees, wasps and ants) and Orthoptera (including crickets, grasshoppers and locusts) are mainly taken, largely based on availability and abundance. Small vertebrates, including small rodents, frogs, lizards and chicks of other birds, may supplement the diet when the opportunity arises.
Great Bustards typically live for around 10 years, but some have been known to live up to 15 years or more. The maximum known life span for the species was 28 years. Adult males seem to have a higher mortality rate than females due mainly to fierce intraspecies fighting with other males during the breeding season. Many males may perish in their first couple of years of maturity due to this cause.
Over 80% of Great Bustards die in the first year of life. Chicks are subject to predation by the fact that they are ground-dwelling birds which are reluctant to fly. Predators of eggs and hatchlings include raptors, corvids, hedgehogs, foxes, badgers, martens, rats and wild boars. The most serious natural predators of nests are perhaps red foxes and hooded crows. Chicks grow very quickly, by 6 months being nearly two-thirds of their adult size, and are predated by foxes, lynxes, wolves, dogs, jackals and eagles. The bold, conspicuous behaviour of the breeding adult male bustard may attract the same large mammalian predators that predate chicks, such as wolves and lynx, while the more inconspicuous female may sometimes be attacked by large eagles. However, predation is rare for adults due to their size, nimbleness and safety in numbers due to their social behaviour.
Occasionally, other natural causes may contribute to mortality in the species, especially starvation in harsh winter months. However, major causes of mortality in recent centuries have been largely linked to human activity, as described below.
The population of this species numbers between 31,000 to 37,000 birds. Between 4,200 and 4,500 are found in east Asia. In recent times, there have been steep declines in population throughout eastern and central Europe and in Asia, particularly in Kazakhstan and Mongolia.
|Native||Afghanistan, Armenia, Austria, Azerbaijan, Bosnia and Herzegovina, Bulgaria, China, Croatia, Czech Republic, France, Georgia, Germany, Greece, Hungary, Iran, Iraq, Italy, Kazakhstan, Kyrgyzstan, Macedonia, Moldova, Mongolia, Montenegro, Morocco, Portugal, Romania, Russia, Serbia, Slovakia, Spain, Syria, Tajikistan, Turkey, Turkmenistan, Ukraine, Uzbekistan|
|Regionally extinct||Algeria, Myanmar, Poland, Sweden, Switzerland, United Kingdom|
|Vagrant||Albania, Belgium, Cyprus, Denmark, Egypt, Finland, Gibraltar, Ireland, Israel, Japan, Korea, Latvia, Luxembourg, Malta, Netherlands, Saudi Arabia, Tunisia|
|Presence uncertain||Lebanon, Pakistan|
Sizeable populations exist in Spain (23,055 birds), Russia (8,000 birds), Turkey (800–3,000 birds), Portugal (1,435 birds) and Mongolia (1,000 birds). Elsewhere, the populations are declining due to habitat loss throughout its range. A sizeable population also exists in Hungary (1,100–1,300 birds) where the Eastern European steppe zone ends, near Dévaványa town and also in the Hortobágy, Nagykunság and Nagy-Sárrét regions. The population is down from a population of 10,000–12,000 before the Second World War.
Threats and conservation status
The Great Bustard is classified as Vulnerable at the species level. There are myriad threats faced by Great Bustards. Increasing human disturbance and land privatisation is expected to lead to habitat loss caused by the ploughing of grasslands, intensive agriculture, afforestation, increased development of irrigation schemes, and the construction of roads, power lines, fencing and ditches. Mechanisation, chemical fertilizers and pesticides, fire and predation by dogs are serious threats for chicks and juveniles, and hunting of adults contributes to high mortality in some of their range countries. Agricultural activity is a major disturbance at nest and, in Hungary, few successful nests are found outside of protected areas.
Two very rare albino Great Bustards from the same nest were killed by electricity cables in Hungary in 2000 and 2003. The bustards, despite their large size, are able to fly at a high velocity and are often mutilated or killed by the cables which are placed in Hungary just at their flying heights. The electricity companies affected will bury only part of the dangerous cables, therefore the authorities are experimenting with fixing fluorescent "Firefly" devices on the most dangerous cables to provide the birds with warning lights. Bustards also occasionally killed by collisions with automobiles or by entanglement in wires.
The Great Bustard was formerly native in Great Britain and a bustard forms part of the design of the Wiltshire Coat of Arms and as supporters for the Cambridgeshire arms. It was hunted out of existence in Britain by the 1840s. In 2004 a project overseeing the reintroduction to Salisbury Plain in Wiltshire using eggs taken from Saratov in Russia was undertaken by The Great Bustard Group, a UK Registered Charity that aims to establish a self-sustaining population of Great Bustards in the UK. They have laid eggs and raised chicks in Britain in 2009 and 2010. Although the Great Bustard was once native to Britain, Great Bustards are considered an alien species under English law. The reintroduction of the Great Bustard to the UK by the Great Bustard Group is being carried out in parallel with researchers from the University of Bath that are providing insight into the habitat of native Great Bustard populations in Russia and Hungary. On January 19, 2011 it was announced that the Great Bustard Project had been awarded EU LIFE+ funding, reportedly to the tune of £1.8 million. In Hungary, where the species is the National Bird, Great Bustards are actively protected. The Hungarian authorities are seeking to preserve the long-term future of the population by active protection measures: the area affected by the special ecological treatment had grown to 15 km2 (5.8 sq mi) by the summer of 2006.
Under the auspices of the Convention on Migratory Species of Wild Animals (CMS), also known as the Bonn Convention, the Memorandum of Understanding (MoU) on the Conservation and Management of Middle-European Populations of the Great Bustard was concluded and came into effect on June 1, 2001. The MoU provides a framework for governments, scientists, conservation bodies and others to monitor and coordinate conservation efforts in order to protect the middle-European populations of the Great Bustard.
- BirdLife International (2013). "Otis tarda". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
- del Hoyo, J; Elliot, A; Sargatal, J (1996). Handbook of the Birds of the World 3. Barcelona: Lynx Edicions. ISBN 84-87334-20-2.
- Great Bustard (Otis tarda) – Information on Great Bustard – Encyclopedia of Life. Eol.org. Retrieved on 2012-08-21.
- Alonso, Juan C.; Magaña, Marina; Alonso, Javier A.; Palacín, Carlos; Martín, Carlos A.; Martín, Beatriz (2009). "The Most Extreme Sexual Size Dimorphism among Birds: Allometry, Selection, and Early Juvenile Development in the Great Bustard (Otis tarda)". The Auk 126 (3): 657. doi:10.1525/auk.2009.08233.
- "The Great Bustard". Great Bustard Group. Retrieved 21 June 2012.
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- Payne-Galleway, Letters to Young Shooters on the Choice and Use of a Gun. General Books LLC (2009), ISBN 978-1-150-35645-2
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- Lane, S. J.; Alonso, J. C.; Alonso, J. A.; Naveso, M. A. (1999). "Seasonal changes in diet and diet selection of great bustards (Otis t. Tarda) in north-west Spain". Journal of Zoology 247 (2): 201. doi:10.1111/j.1469-7998.1999.tb00984.x.
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The Great Bustard, Otis tarda, is in the bustard family, the only member of the genus Otis. It breeds in southern and central Europe, where it is the largest species of bird, and across temperate Asia. European populations are mainly resident, but Asian birds move further south in winter. Sizeable populations exist in Hungary, Portugal, Slovakia, Russia, Spain and Kurdistan, as well as a very small population in Romania, but the species is declining due to habitat loss throughout its range.
The male of this huge bird is possibly the heaviest living flying animal, alongside the similarly sized Kori Bustard. An adult male typically is 90–110 cm (3.0–3.6 ft) long with a 2.1–2.5 m (6.9–8.2 ft) wingspan and usually weighs from 10 to 16 kg (22 to 35 lb). The heaviest known bird was about 21 kg (46 lb), although larger specimens have been reported but not verified. An adult male is brown above and white below, with a long grey neck and head. The breast and lower neck sides are chestnut. In the breeding season, the male has long white neck bristles. In flight, the long wings show large areas of white.
The female is 30% smaller (typically 80 cm in length and 1.8 m across the wings) and one-third the weight of the male, averaging 3.5–5 kg (7.7–11 lb). Perhaps because of this, there is a skewed sex ratio of about 1.5:1 female to male. The breast and neck of the female are buff. Both sexes are usually silent. Immature birds resemble the female.
Before mating, the males moult into their breeding plumage around January. Like other bustards, the male Great Bustard has a flamboyant display showing much white, mainly from the undertail, and withdrawing the head. The Great Bustard breeds in March, and a single male may mate with up to 5 females. All breeding Great Bustards also moult again from June to September.
2-3 olive or tan coloured, glossy eggs are laid in a small ground scrape. The female incubates the eggs alone for around 4 weeks. The chicks almost immediately leave the nest after they hatch, although they do not move very far from their mother until they are at least 1 year old. Males usually start to mate from about 5 years old. Great Bustards typically live for around 10 years, but some have been known to live up to 15 years or more.
This bird's habitat is open grassland, although it can be found on undisturbed cultivation. It has a stately slow walk, and tends to run when disturbed rather than fly. It is gregarious, especially in winter. This species is omnivorous, taking seeds, insects and other small creatures, including frogs and beetles.
Two very rare albino Great Bustards from the same nest were killed by electricity cables in Hungary in 2000 and 2003. The bustards, despite their large size, are able to fly at a high velocity (60 kilometre/hour) and are often mutilated or killed by the cables which are placed in Hungary just at their flying heights. The electricity companies affected will bury only part of the dangerous cables, therefore the authorities are experimenting with fixing fluorescent "Firefly" devices on the most dangerous cables to provide the birds with warning lights. (The funds available are not sufficient for a full treatment of the problem.)
Populations vary from region to region with 1,400 Great Bustard individuals residing in Portugal, another large population of around 6,000-7,000 birds resident near Saratov in Russia and 23,000 individuals in Spain. Sizeable populations still exist in Hungary, where the Eastern European steppe zone ends, near Dévaványa town and also in the Hortobágy, Nagykunság and Nagy-Sárrét regions. There were 1,350 birds in February 2006, down from a population of 10,000-12,000 before the Second World War. The Hungarian authorities are seeking to preserve the long-term future of the population by active protection measures: the area affected by the special ecological treatment had grown to 15 square kilometres by the summer of 2006.
The Great Bustard was formerly found in the south of the British Isles (a bustard forms part of the design of the Wiltshire Coat of Arms) but was hunted out of existence by the 1840s. In 2004 a reintroduction to Salisbury Plain in Wiltshire using eggs taken from Saratov in Russia was undertaken by The Great Bustard Group, a U.K. Registered Charity that aims to establish a self-sustaining population of Great Bustards in the UK. This reintroduction project continues to see successful hatchings.
- BirdLife International (2004). Otis tarda. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 11 May 2006. Database entry includes justification for why this species is vulnerable
- Gorman, Gerard (1996). The Birds of Hungary. London: Helm (A&C Black). ISBN 0-7136-4235-1.
- Meissner, Hans Otto (1963). Unknown Europe. trans. Florence and Isabel McHugh. London and Glasgow: Blackie & Sons. pp. 125-139.