Sarus Crane

Identification

The adult sarus crane is very large, with grey wings and body, a bare red head and part of the upper neck, a greyish crown, and a long, greenish-grey, pointed bill. In flight, the long neck is held straight, unlike that of a heron, which folds it back, and the black wing tips can be seen; the crane's long, pink legs trail behind them. This bird has a grey ear covert patch, orange-red irises, and a greenish-grey bill. Juveniles have a yellowish base to the bill and the brown-grey head is fully feathered.<p>The bare red skin of the adult's head and neck is brighter during the breeding season. This skin is rough and covered by papillae, and a narrow area around and behind the head is covered by black, bristly feathers. The sexes do not differ in plumage, although males are on average larger than females; males of the Indian population can attain a maximum height around 180 cm (5.9 ft), making them the world's tallest extant flying bird. The weight of nominate race individuals is 6.8–7.8 kg (15–17 lb), while five adults of A. a. sharpii averaged 8.4 kg (19 lb). Across the distribution range, their weight can vary from 5 to 12 kg (11 to 26 lb), height typically from 115 to 167 cm (45 to 66 in), and wingspan from 220 to 250 cm (87 to 98 in).<p>While individuals from northern populations are among the heaviest cranes, alongside the red-crowned and wattled cranes, and the largest in their range, birds from Australia tend to be smaller. In Australia, the sarus can easily be mistaken for the more widespread brolga. The brolga has the red colouring confined to the head and not extending onto the neck. Body mass in Australian sarus cranes was found to average 6.68 kg (14.7 lb) in males and 5.25 kg (11.6 lb) in females, with a range for both sexes of 5.0 to 6.9 kg (11.0 to 15.2 lb). Thus, Australian sarus cranes average about 25% lighter than the northern counterparts and are marginally lighter on average than brolgas.

Taxonomy

In 1743 the English naturalist George Edwards included an illustration and a description of the sarus crane in the first volume of his A Natural History of Uncommon Birds. He used the English name "The Greater Indian Crane". Edwards based his hand-coloured etching on a live specimen that he had drawn at the London home of the Admiral Charles Wager. When in 1758 the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the tenth edition, he placed the sarus crane or Grus major Indica in Latin with the herons and cranes in the genus Ardea. Linnaeus included a brief description, coined the binomial name Ardea antigone and cited Edwards' work. The specific epithet is based on the Greek mythology. Antigone was the daughter of the Trojan king Laomedon. She was turned into a stork for comparing her own beauty with the goddess Hera. Linnaeus appears to have confused this myth with that of Gerana, queen of the pigmies, who considered herself more beautiful than Hera and was turned into a crane. The sarus crane was formerly placed in the genus Grus, but a molecular phylogenetic study published in 2010 found that the genus, as then defined, was polyphyletic. In the resulting rearrangement to create monophyletic genera, four species, including the sarus crane, were placed in the resurrected genus Antigone that had originally been erected by German naturalist Ludwig Reichenbach in 1853.<p>Edward Blyth published a monograph on the cranes in 1881, in which he considered the "sarus crane" of India to be made up of two species, Grus collaris and Grus antigone. Most modern authors recognize one species with three disjunct populations that are sometimes treated as subspecies, although the status of one extinct population from the Philippines is uncertain. The sarus cranes in India (referred to as A. a. antigone) are the largest, and in Myanmar to the east are replaced by a population that extends into Southeast Asia (referred to as A. a. sharpii). Sarus cranes from the Indian subcontinent are differentiated from the south-eastern population by the white collar below their bare head and upper neck, and their white tertiary remiges. The population in Australia (initially placed in A. a. sharpii (sometimes spelt sharpei but amended to conform to the rules of Latin grammar) was separated and named A. a. gilliae, sometimes spelt gillae or gillii), prior to a genetic analysis. A 2005 genetic analysis suggests that these three populations are representatives of a formerly continuous population that varied clinally. The Australian subspecies was designated only in 1988, with the species itself first noticed in Australia in 1966 and regarded as a recent immigrant. Native Australians, however, differentiated between the sarus and the brolga, calling the sarus "the crane that dips its head in blood.” Sarus cranes of the Australian population are similar to those in Southeast Asia in having no white on the neck and tertiary remiges, but are distinguished by a larger grey patch of ear coverts. The Australian population shows the most recent divergence from the ancestral form with an estimated 3000 generations of breeding within Australia. An additional subspecies, A. a. luzonica, was suggested for the population — now extinct — in the Philippines. No distinctive characteristic is known of this disappeared population.<p>Analysis of mitochondrial DNA from a limited number of specimens suggests that gene flow occurred within the continental Asian populations until the 20th-century reductions in range, and that Australia was colonized only in the Late Pleistocene, some 35,000 years ago. This has been corroborated by nDNA microsatellite analyses on a large and widely distributed set of individuals in the sample. This study suggests further that the Australian population shows low genetic variability. As there exists the possibility of (limited) hybridization with the genetically distinct brolga, the Australian sarus crane can be expected to be an incipient species.<p>The common name sarus is from the Hindi name (sāras) for the species. The Hindi word is derived from the Sanskrit word sarasa for the "lake bird", (sometimes corrupted to sārhans). British soldiers in colonial India who hunted the birds corrupted the name to serious or even cyrus.

Scientific name

Antigone antigone

Authority

(Linnaeus, 1758)

Order

Gruiformes

Family

Gruidae

Genus

Antigone

Range and habitat

The species has historically been widely distributed on the lowlands of India along the Gangetic plains, extending south to the Godavari River, west to coastal Gujarat, the Tharparkar District of Pakistan, and east to West Bengal and Assam. The species no longer breeds in Punjab, though it winters regularly in the state. Sarus cranes are rare in West Bengal and Assam, and are no longer found in the state of Bihar. In Nepal, its distribution is restricted to the western and central lowland plains, with most of the population occurring in Rupandehi, Kapilvastu, and Nawalparasi districts.<p>Two distinct populations of sarus cranes occur in Southeast Asia: the northern population in China and Myanmar, and the southern population in Cambodia and Vietnam. The sarus used to extend to Thailand and further east into the Philippines, but may now be extinct in both these countries. In 2011, 24 captive-bred cranes raised from five founders were reintroduced into Thailand. A reasonably sized population of over 150 breeding pairs of sarus cranes has been discovered in the Ayeyarwadi delta, Myanmar, with additional cranes confirmed in the states of Kachin, Shan, and Rakhine. In Australia they are found only in the north-east, and are partly migratory in some areas. The global range has shrunk and the largest occupied area, and the largest known population, is in India. Increasing paddy fields accompanied by an increase in the network of irrigation canals during and prior to the Green Revolution may have facilitated increases in the distribution and numbers of sarus cranes due to an increase in reliable moisture levels in various locations in India. Although now found mainly at low elevations on the plains, some historical records exist from highland marshes further north in Harkit Sar and Kahag in Kashmir. The sarus crane breeds in some high elevation regions such as near the Pong Dam in Himachal Pradesh, where populations may be growing in response to increasing rice cultivation along the reservoir. In rice-dominated districts of Uttar Pradesh, sarus crane abundance (estimated as occupancy) was highest in the western districts, intermediate in the central districts, and minimal in the eastern districts. Sarus crane abundance was positively associated with percentage of wetlands on the landscape, and negatively with the percentage of area under rice cultivation.<p>Field surveys and detailed observations of sarus cranes increased greatly in Myanmar by 2022, with a strong focus on the Ayeyarwadi delta. Surveys across multiple townships discovered over 150 pairs of breeding Sarus Cranes (with a maximum of 185 nests monitored in 2018), suggesting that the population in this region is far higher than was previously known. The vast majority of nests were located in rice paddies, with few in flooded grass patches.<p>Until recently, little was known of sarus crane ecology from Australia. Breeding records (confirmed sightings of nests with eggs, or of adult birds with flightless young) were known from only three locations, all in the Gulf Plains in Queensland. Two records are from near Normanton town; one of adults with flightless chicks seen about 30 km west of the town and another of adults incubating eggs seen 7-km south of the town. The third record is a one-month study that provides details of 32 nests located within 10-km around Morr Morr cattle station in the Gilbert River floodplains. A 3,000-km survey along the Gulf of Carpentaria located 141 territorial, breeding pairs spread out across the floodplains of the Mitchell, Gilbert, and Flinders Rivers. Carefully mapping of breeding areas of sarus cranes in Australia is needed to understand their distribution range. They are uncommon in Kakadu National Park, where the species is often hard to find among the more numerous brolgas. Flocks in the non-breeding season are commonly seen in the Atherton Tablelands in eastern Queensland.<p>In India, sarus cranes preferentially use wetlands for nesting, but also nest in uncultivated patches amid flooded rice paddies (called khet-taavadi in Gujarat), and in the rice paddies especially when wetlands are not available to breeding pairs. Breeding pairs are territorial and prefer to forage in natural wetlands, though wetland crops such as rice and wheat are also frequented. In south-western Uttar Pradesh, sarus cranes were found in wetlands of all sizes with larger numbers in larger wetlands. In Australia, wintering, nonbreeding sarus cranes forage in areas with intensive agriculture (primarily maize, sugarcane, groundnuts) and smaller patches of cattle-grazing areas in the Atherton Tablelands in eastern Queensland. They were observed to feed on grain, nuts, and insects from a range of crop fields, including stubble of maize and peanut crops, hay crops, fields with potato, legumes, and seed crops, and after harvest in fields of sugarcane, grass, and fodder crops. Territorial, breeding sarus crane pairs in northern Queensland along the Gulf of Carpentaria use a range of habitats, but preferentially use low, open woodland on quaternary alluvial plains in outer river deltas and levees with a vegetation of Lysiphyllum cunninghamii, Eucalyptus microtheca, Corymbia confertiflora, Melaleuca spp., Excoecaria parvifolia, Atalaya hemiglauca, Grevillea striata, Eucalyptus leptophleba, C. polycarpa, C. confertiflora, and C. bella.

Migration

Complete migrants

Behavior

Migration pattern: Complete migrants.

Conservation

Population trend: declining.

Population trend

declining