Montagu's harrier

The Montagu's harrier (Circus pygargus) is a migratory bird of prey of the harrier family. Its common name commemorates the British naturalist George Montagu.

Montagu's harrier
Montagu's harrier (Circus pygargus)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Circus
Species:
C. pygargus
Binomial name
Circus pygargus
Circus pygargus distribution map
Range of C. pygargus      Breeding range     Wintering range
Synonyms

Falco pygargus Linnaeus, 1758

Taxonomy

The first formal description of Montagu's harrier was by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Falco pygargus.[2] The genus Circus was introduced by the French naturalist Bernard Germain de Lacépède in 1799.[3][4] The genus name is derived from the Ancient Greek. Circus is from kirkos, referring to a bird of prey named for its circling flight (kirkos, "circle"), probably the hen harrier, and pygargus is Modern Latin derived from Greek pugargos, from puge,"rump" and argos, "shining white". The species name was formerly used for the hen harrier before Montagu's was identified as a different species.[5]

Montagu's Harrier Male
Montagu's Harrier Male, Rollapadu Wildlife Sanctuary, Andhra Pradesh, India

Identification

Montagu's harrier (Circus pygargus) In flight
Montagu's harrier (Circus pygargus) In flight from Tal Chappar

Plumage

Sexual dimorphism is particularly apparent in the plumage of this species. Adult males are characterized by their overall pale grey plumage contrasting with black wingtips. Compared with other harriers this species has characteristic black bands along the secondaries, both above and below the wing and rusty streaks on belly and flanks. Adult females have a broadly similar plumage to that of pallid and hen harriers. The underparts are mostly pale yellow-brown, the belly with longitudinal stripes and the wing coverts spotted. The upper parts are uniform dark brown except for the white upper tail coverts ("rump"), and the sightly paler central wing coverts.

The juvenile plumage resembles that of the female, but differs by the belly and under wing coverts which are not spotted, but uniformly red brown in colour.

A melanistic form occurs regularly in this species. In this form the male is much darker than usual, with a black head, brownish black above and grey underparts. The melanistic female is entirely chocolate brown except for grey flight feathers. Partially melanistic morphs can also be found.

Flight

The Montagu's harrier has a particularly graceful flight, with powerful and elegant wingbeats which give an impression of buoyancy and ease. In true harrier fashion it searches the countryside, flying low, and generally holds its wings with a marked positive dihedral.

Montagu's harrier (Circus pygargus) grounded
Montagu's harrier (Circus pygargus) from Tal Chappar

Dimensions

The Montagu's harrier is a deceptively small raptor, though it appears larger because of its large wing surface compared to small body weight, which gives it a typically buoyant flight. The female is larger than the male because the female needs to produce eggs, however this is not apparent in the field.

  • Wingspan: 97–115 cm (38–45 in)
  • Length: 43–47 cm (17–19 in) (tail: 16–18 cm (6.3–7.1 in))
  • Weight (average):
    • Male: 265 g (9.3 oz)
    • Female: 345 g (12.2 oz)

Risk of confusion

The Montagu's harrier can be confused with several species that exist within the same range. The most similar are the hen harrier and the pallid harrier. The male is easily distinguished from other species as its plumage is distinctly darker and more mottled than in the males of hen or pallid harriers. However, distinguishing females and juveniles is more difficult. Usually the Montagu's harrier appears more slender in flight than the hen harrier with a longer tail, longer and narrower wings and more pointed "hands". Also its flight is more elegant than the hen harrier, with more elastic, almost tern-like wingbeats. The distinction between female pallid and Montagu's harriers is the most delicate and can only be made in good conditions as the proportions are similar. The best recognition character is the pale collar around the neck of female and juvenile pallid harriers which is not present in the Montagu's.

Habitat

This species can be found in a middle-latitude band of predominantly temperate climates, but also in Mediterranean, and boreal zones. Although it has been found nesting up to 1,500 m (4,900 ft), it is essentially a lowland species, and nests mostly in broad river valleys, plains, and levels bordering lakes and the sea. It can breed in wetlands, though these are often smaller and drier than those used by the marsh harrier. It also utilizes heaths, dunes, moors, and can be found in the steppe. It adapts to shrublands in gorse or heather and to areas planted with young conifers.

Montagu's Harrier, juvenile, Bangalore, India
Adult Female

When no other suitable habitat is available this harrier will nest in agricultural farmlands where it is vulnerable to early harvesting. Amongst these it chooses especially grasslands and cereal crops such as wheat, barley, oats and colza. In western Europe, up to 70% of the population breeds in artificial habitats.

Montagu's Harrier- Male
Adult Male

In short, for breeding the Montagu's harrier requires a large open area, with sufficiently tall ground vegetation to afford cover without being overgrown. It favours posts on which both male and female can rest and survey the breeding area: these can be fenceposts, small trees, or rocky outcrops. When hunting, in any season, it prefers areas of low or sparse vegetation where prey is more visible. Densely settled areas are generally avoided and it is highly susceptible to disturbance.

Food and foraging methods

The diet consists mainly of small rodents, small birds, bird eggs, reptiles (including snakes) and large insects (mainly Orthoptera, which are numerically the most common).[6]

As this bird has a wide distribution, it will take whatever prey is available in the area where it nests; in the northern range it will mainly take ground squirrels and rabbits, whereas in southern Europe, it mostly takes small reptiles and large insects. In areas where the food supply is composed almost exclusively of rodents, the breeding success depends greatly on the cyclic fluctuations of vole populations.[7] At times they regurgitate.

Prey is caught while flying along fixed routes at low heights and constant low speeds (c. 30 km/h (19 mph)), as is typical of harriers. The flight is considered lighter and more dexterous than other harriers enabling it to take more agile prey. When possible it often follows the edges of various vegetation to catch its prey by surprise. This is taken after a short stoop, though fast running animals and flying birds can be chased over a short distance.

During the breeding season, the male will provision the female and later the young with food. The rate of provisioning increases from 5 to 6 times per day during incubation to 7 to 10 times per day when young have hatched, though the male can be handicapped by wet, foggy or windy weather. In a manner typical of harriers, prey is passed between partners in the air: The female flies underneath the male, who drops the prey for her to catch. The male hunts over a large area up to 12 km (7.5 mi) away from the nest. The female hunts closer to the nest, up to 1 km (0.62 mi) away, and only after the young have hatched.

Status and distribution

This species can still be found throughout most of the Western Palearctic. In most European countries there is at least a small population, except in Norway where it is not present. The breeding range extends as far east as the Urals, whereas the most western population is that of Portugal. Breeding also occurs in northern Africa, mostly in Morocco. In Great Britain, the species is limited to southern England. In Ireland the species is rarely seen, and mainly in the South, although there are a number of breeding records, the most recent from 1971.[8] Despite having a wide distribution, this bird is not common in many areas and has strong populations only in France, Spain, Russia, Belarus and Poland where the greater part of the European population can be found. Breeding sites frequently change, with some sporadic nesting occurring outside known breeding areas, however clear signs of reduced range are apparent and are associated with population decline.

Status in Britain

Montagu's harrier is a rare breeding bird in Britain. There are two breeding areas – the area surrounding The Wash, and downland areas of southern England, from Dorset and Hampshire north to Oxfordshire. Away from these areas it occurs only as a scarce migrant. One site, Estuary Farm, near North Wootton in west Norfolk, a special observation area was negotiated with local landowners, so that pressure could be taken off other nesting pairs.[9] In 2005, a pair bred on the Holkham estate.[10] In 2015, it was reported that some Montagu's harrier were nesting at Blacktoft Sands, Humberside.[11]

Population trends

The population for the western Palearctic is estimated at 35,000–50,000 pairs. The global population is unknown and could be anything between 150,000 and 200,000 individuals(Birdlife International, 2004). This uncertainty is due to the fact that most of the world's population is situated in Russia and former Soviet republics where it is not quantified.

The evolution has been paradoxical throughout the 20th century. In the beginning of the century up to the 1940s, during a period when other raptors greatly decreased because of human persecution, the Montagu's harrier actually increased its population and breeding range, breeding for the first time in Denmark in the 1900s, and greatly increasing elsewhere. However, from the 1940s onwards it has decreased rapidly. This is due to several negative factors: first, the massive use of agricultural pesticides such as DDT and other environmental poisons was extremely detrimental to the harriers themselves, as well as rarefying their prey, in particular large insects. The modification of agricultural practises, with an evolution towards more intensive farming also puts pressure on harriers, with faster growing crops preventing those birds that nest in farmlands from finishing their nidification before their clutches are destroyed by harvesting machines. Despite a generally negative trend there are local cases when the population has increased, such as in Sweden or in Germany[12] in the 1990s. These local trends show that while they have access to suitable habitats and food supply there can still be positive developments.

Social behaviour and breeding

It can be both solitary and gregarious at times, both during the breeding season and in winter quarters. A breeding pair may associate with others to form loose colonies, with as many as 30 nests in the same area, sometimes as close as 10 m (33 ft) apart. Semi-colonial nesting is not due to a shortage of nesting sites, but arises rather from the need to provide a better defence against predators.[13] The actual area defended by both partners covers only 300–400 m (980–1,310 ft) around the nest, and in case of colonial nesting the response to predators may be communal. Other species attacked and mobbed include large raptors, corvids, and foxes.

Circus pygargus MWNH 0857
Egg, Collection Museum Wiesbaden

Reproduction begins with the return of both partners to the nesting site, at which point both male and female will start displaying. The display consists of various sky-dances and aerobatic figures that vary according to each individual. Both sexes will display, crying loudly, though the males' displays are more frequent and spectacular. Montagu's harriers breed for the first time when two or three years old, but occasionally one year old females may attempt to nest. Pairs form on the territory, when returning from migration. As the birds are tied to their former nesting sites, they probably mate with the same partner every year. The nest is built by the female, always in tall vegetation. It is a simple construction made of grass, used only for one season. The female lays 3 to 5 eggs which are incubated for 27–40 days. The young leave the nest after 28–42 days and are independent two weeks later.

The males may be polygamous, then having to feed two females and later two broods, either simultaneously or consecutively.

Migration

The Montagu's harrier is a long distance migrant. Birds from Eurasia spend the winter in sub-Saharan Africa, while those from the eastern part of the range migrate to the Indian subcontinent. In Europe, the first birds start to move at the beginning of August and most have left by mid-October. They travel over a broad front, crossing the Mediterranean at various points, and only a small number are observed at migration choke points. Western birds don't go further south than the gulf of Guinea, but some eastern birds travel as far as South Africa. In Africa, their diet is composed mostly of insects and birds, and it is possible that they follow locust swarms.[14]

Youngmonties
Young Montagu's harriers during relocation.

Spring return peaks in April, and most birds have arrived by May though there is evidence that first-year juveniles spend their first summer in the winter quarters

Conservation issues

In western Europe, an estimated 70% of breeding pairs nest in agricultural farmlands, especially cereal crops. This makes the Montagu's harrier a very vulnerable species, and very dependent on nest protection. Bird protection non-governmental organizations participate in their protection, in collaboration with concerned landowners. Once a nest is spotted in a field, it can be safeguarded either by relocating it to a safer area or by creating a protected space which will not be harvested.[15] In France and in the Iberian Peninsula, an average 60% of nestlings are saved by this kind of measures.[16]

References

  1. ^ BirdLife International (2013). "Circus pygargus". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
  2. ^ Linnaeus, C. (1758). Systema Naturæ per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Volume 1 (in Latin) (10th ed.). Holmiae:Laurentii Salvii. p. 89.
  3. ^ Lacépède, Bernard Germain de (1799). "Tableau des sous-classes, divisions, sous-division, ordres et genres des oiseux". Discours d'ouverture et de clôture du cours d'histoire naturelle (in French). Paris: Plassan. p. 4. Page numbering starts at one for each of the three sections.
  4. ^ Mayr, Ernst; Cottrell, G. William, eds. (1979). Check-list of Birds of the World. Volume 1 (2nd ed.). Cambridge, Massachusetts: Museum of Comparative Zoology. p. 316.
  5. ^ Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. pp. 109, 325. ISBN 978-1-4081-2501-4.
  6. ^ Arroyo, B.E. (1997). "Diet of Montagu's Harrier Circus pygargus in central Spain: analysis of temporal and geographic variation". Ibis. 139: 664–672. doi:10.1111/j.1474-919x.1997.tb04689.x.
  7. ^ Salamolard, M.; Butet, A.; Leroux, A.; Bretagnolle, V. (2000). "Responses of an avian predator to variations in prey density at a temperate latitude". Ecology. 81: 2428–2441. doi:10.1890/0012-9658(2000)081[2428:ROAAPT]2.0.CO;2. ISSN 0012-9658.
  8. ^ "Irish Birding".
  9. ^ Evans, Lee G.R. (1996). The Ultimate Site Guide to Scarcer British Birds. ISBN 1-898918-15-5.
  10. ^ "Rare Harriers Breed at Holkham" (PDF). Holkham Newsletter (11). 2006.
  11. ^ "UK's rarest bird of prey nesting at Humber site". Scunthorpe Telegraph. 22 June 2015.
  12. ^ Belting, C.; Krüger, R.M. (2002). "Populationsentwicklung und Schutzstrategien für die Wiesenweihe Circus pygargus in Bayern" [Population development and strategies for the protection of Montagu's Harrier in Bavaria] (PDF). Ornithologischer Anzeiger (in German). 87: 87–92.
  13. ^ Arroyo, Beatriz; Mougeot, François; Bretagnolle, Vincent (2001). "Colonial breeding and nest defence in Montagu's harrier (Circus pygargus)". Behavioral Ecology and Sociobiology. doi:10.1007/s002650100342. ISSN 0340-5443.
  14. ^ "Montagu's harrier migration". werkgroepgrauwekiekendief.nl.
  15. ^ "Nest protection put into practice at grauwekiekendief.nl". werkgroepgrauwekiekendief.nl.
  16. ^ Arroyo, Beatriz; García, Jesús T.; Bretagnolle, Vincent (November 2002). "Conservation of the Montagu's harrier (Circus pygargus) in agricultural areas". Animal Conservation. 5 (4): 283. doi:10.1017/s1367943002004031.
  • Cramp, S.; Simmons, K.E.L., eds. (1980). The Birds of the Western Palearctic. Vol. II. Oxford University Press. ISBN 0-19-857505-X.
  • Gensbøl, Benny (1989). Collins guide to the Birds of Prey of Britain and Europe North Africa and the Middle East. William Collins Sons and Co Ltd. ISBN 0-00-219176-8.

Further reading

Identification

External links

Blacktoft Sands RSPB reserve

Blacktoft Sands RSPB reserve is a nature reserve in the East Riding of Yorkshire, England. It is managed by the Royal Society for the Protection of Birds, which leases the site from Associated British Ports.The site is on the southern bank of the Ouse, opposite the village of Blacktoft, and is a wetland. Being at the beginning of the Humber Estuary, the water is slightly saline.

The reserve's tidal reedbed is the largest in England.

It is known for its wetland breeding birds, including marsh harrier, bittern and bearded tit. In 2015, it was reported that some Montagu's harrier were nesting at Blacktoft.

Bonomi BS.20 Albanella

The Bonomi BS.20 Albanella (English: Montagu's harrier) was a performance sailplane designed and built in Italy in the mid-1930s. Rather little is known about it; either one or two were constructed.

George Montagu (naturalist)

George Montagu (1753 – 20 June 1815) was an English army officer and naturalist. He was known for his pioneering Ornithological Dictionary of 1802, which for the first time accurately defined the status of Britain's birds. He is remembered today for species such as the Montagu's harrier, named for him.

Harrier (bird)

A harrier is any of the several species of diurnal hawks sometimes placed in the Circinae sub-family of the Accipitridae family of birds of prey. Harriers characteristically hunt by flying low over open ground, feeding on small mammals, reptiles, or birds. The young of the species are sometimes referred to as ring-tail harriers. They are distinctive with long wings, a long narrow tail, the slow and low flight over grasslands and skull peculiarities. The harriers are thought to have diversified with the expansion of grasslands and the emergence of C4 grasses about 6 to 8 million years ago during the Late Miocene and Pliocene.

Heath

A heath () is a shrubland habitat found mainly on free-draining infertile, acidic soils and is characterised by open, low-growing woody vegetation. Moorland is generally related to high-ground heaths with—especially in Great Britain—a cooler and damper climate.

Heaths are widespread worldwide, but are fast disappearing and considered a rare habitat in Europe. They form extensive and highly diverse communities across Australia in humid and sub-humid areas where fire regimes with recurring burning are required for the maintenance of the heathlands. Even more diverse though less widespread heath communities occur in Southern Africa. Extensive heath communities can also be found in the California chaparral, New Caledonia, central Chile and along the shores of the Mediterranean Sea. In addition to these extensive heath areas, the vegetation type is also found in scattered locations across all continents, except Antarctica.

Krokų Lanka

Krokų Lanka is the only lake of marine origin in Lithuania and the largest lake in the Šilutė District Municipality. It is located in the Nemunas Delta Regional Park on the Baltic Sea shore near Nemunas Delta and Ventė Cape. It covers a territory of 788 ha. Aukštumala bog, covering 3018 ha and used for peat production since 1882, is located just north of the lake and Mingė village is located on the western bank. In the south a narrow strip of water connects the lake with Atmata, a branch of the Neman River.

Krokų Lanka was created when alluvial deposits from the Neman River separated a part of the Curonian Lagoon. The lake is very shallow, with greatest depth of only 2.5 meters, and overgrown with water plants. It is poised to eventually turn into a bog but now it is a paradise for a variety of water birds, including Eurasian bittern (Botaurus stellaris), greylag goose (Anser anser), Montagu's harrier (Circus pygargus), black-tailed godwit (Limosa limosa), Eurasian curlew (Numenius arquata). In spring and fall the lake attracts large groups of migratory birds. Krokų Lanka is also important area for spawning fishes. To protect this environment botanical and zoological reserve, covering 1214 ha, was established in 1992.

Lauwersmeer National Park

Lauwersmeer National Park (Dutch: Nationaal Park Lauwersmeer) is a national park in the provinces of Friesland and Groningen in the Netherlands. It consists of the southern and eastern parts of the Lauwersmeer (previously Lauwerszee).

Mayureshwar Wildlife Sanctuary

Mayureswar Wildlife Sanctuary is located in Tehsil Baramati in Pune district in Maharashtra, India. It is 72 km from Pune and 35 km from Daund.

Modes of reproduction

Animals make use of a variety of modes of reproduction to produce their young. Traditionally this variety was classified into three modes, oviparity (embryos in eggs), viviparity (young born live), and ovoviviparity (intermediate between the first two).

However, each of those so-called traditional modes covered a wide range of diverse reproductive strategies. The biologist Thierry Lodé has accordingly proposed five modes of reproduction based on the relationship between the zygote (the fertilised egg) and the parents. His revised modes are ovuliparity, with external fertilisation; oviparity, with internal fertilisation of large eggs containing a substantial nutritive yolk; ovo-viviparity, that is oviparity where the zygotes are retained for a time in a parent's body, but without any sort of feeding by the parent; histotrophic viviparity, where the zygotes develop in the female's oviducts, but are fed on other tissues; and hemotrophic viviparity, where the developing embryos are fed by the mother, often through a placenta.

Monegros Desert

The Monegros Desert or Desierto de los Monegros is a semidesert in Aragón, northeastern Spain, spanning the provinces of Zaragoza and Huesca. It is a semi arid zone prone to frequent droughts. It is noted for its annual electronic music festival held in mid-July, the Monegros Festival.

Montagu

Montagu may refer to:

Montagu (surname)

Nätsi-Võlla Nature Reserve

Nätsi-Võlla Nature Reserve is a nature reserve situated in western Estonia, in Pärnu County, made up of several bogs that together form the largest bog area in Pärnu County.

It is an internationally important bird area, with species such as golden eagle, merlin and ruff. The bogs are rich in cloudberries and cranberries. The bogs of Nätsi-Võlla host numerous migratory species, such as the tundra swan (Cygnus columbianus). It also sees an annual congregation of numerous wader species. The bogs are also home to a significant percentage of the total national breeding population of such species as common crane (Grus grus) and black-tailed godwit (Limosa limosa). Other birds found here are whooper swan (Cygnus cygnus), Montagu's harrier (Circus pygargus), Eurasian golden plover (Pluvialis apricaria) and Eurasian eagle-owl (Bubo bubo)

Pallid harrier

The pale or pallid harrier (Circus macrourus) is a migratory bird of prey of the harrier family. The scientific name is derived from the Ancient Greek. Circus is from kirkos, referring to a bird of prey named for its circling flight (kirkos, "circle"), probably the hen harrier and macrourus is "long-tailed", from makros, "long" and -ouros "-tailed".It breeds in southern parts of eastern Europe and central Asia (such as Iran) and winters mainly in India and southeast Asia. It is a very rare vagrant to Great Britain and western Europe, although remarkably a juvenile wintered in Norfolk in the winter of 2002/2003. In 2017 a pair of pallid harriers nested in a barley field in the Netherlands; they raised four chicks.This medium-sized raptor breeds on open plains, bogs and heathland. In winter it is a bird of open country.

Pešter

The Pešter plateau (Serbian: Пештерска висораван/Pešterska visoravan; Albanian: Rrafshnalta e Peshterit), or simply Pešter (Serbian Cyrillic: Пештер, pronounced [pɛ̌ʃtɛr]; Albanian: Peshter), is a karst plateau in southwestern Serbia, in the Raška (or Sandžak) region. It lies at the altitude of 1150–1492 m, (Kuljarski vrh) at 1492 meters. The territory of the plateau is mostly located in the municipality of Sjenica, with parts belonging to Novi Pazar and Tutin. The name of the region comes from the word pešter, which is a slavic word for cave.

Ravni Kotari

Ravni kotari (Croatian: [ravniː kôtaːri]) is a geographical region in Croatia. It lies in northern Dalmatia, around Zadar and east of it. It is bordered by Bukovica to the northeast, lower Krka to the southeast, and the Adriatic Sea. The largest settlement in the region is the town of Benkovac. Other large settlements are Zemunik Donji (where Zadar Airport is located), Polača, Poličnik, Galovac, Gorica, Škabrnja, Posedarje, Pridraga, Novigrad, and Stankovci.

Riether Werder

The Riether Werder, also Riethscher Werder (Polish Ostrów), is an island in the Neuwarper See, a bay in the Stettin Lagoon. It is the only island in the lagoon on German territory.

The first recorded mention of the island dates to the year 1252, when Duke Barnim I of Pomerania gifted this island along with other possessions to Eldena Abbey. It was then given it the Slavic name Wozstro. The present name of the island is derived from the village of Rieth on the southern shore of the bay.

The island belongs to the district of Vorpommern-Greifswald in the German state of Mecklenburg-Vorpommern and lies in the extreme northeast of Germany. It has national importance as a bird island. It is 0.79 km² in area and lies about a kilometre from the south and west shore of the Neuwarper See. The sea border with Poland runs immediately past the eastern tip of the island.

Rare bird species such as the common tern and the snipe may be encountered here. White-tailed eagle, Montagu's harrier, marsh harrier, red kite, black kite, kestrel, hobby, honey buzzard and common buzzard are also found here. Access to the island is forbidden; like the west shore of the Neuwarper See it is part of the Altwarp Inland Dunes, Neuwarper See and Riether Werder Nature Reserve.

Rosenannon Downs

Rosenannon Downs is a nature reserve in mid Cornwall, England, UK, being designated Rosenannon Bog and Downs Site of Special Scientific Interest (SSSI), noted for its biological characteristics. The site supports a wide variety of flora and fauna and includes Bronze Age barrows. Conservation work is carried out on the site by the owners, the Cornwall Wildlife Trust.

Tiste Bauernmoor

The Tiste Bauernmoor (German: Tister Bauernmoor) is an area of raised bog on the Lüneburg Heath in north Germany that was designated as a nature reserve on 2 May 2002. It has an area of 570 hectares (1,400 acres) and belongs, together with the Ekelmoor, Avensermoor and Everstofer Moor, to the large Ekelmoor moorland region that has a total area of 1,220 hectares (3,000 acres).

Veliko Blato (ornithological reserve)

Veliko Blato is an ornithological reserve on the Croatian island of Pag.

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