Ruddy shelduck

The ruddy shelduck (Tadorna ferruginea) is a member of the shelduck genus Tadorna in the wildfowl family Anatidae. The bird was first described in 1764 by the German zoologist and botanist Peter Simon Pallas who named it Anas ferruginea, but later it was transferred to the genus Tadorna with the other shelducks. Some authorities place it in the genus Casarca along with the South African shelduck (T. cana), the Australian shelduck (T. tadornoides) and the paradise shelduck (T. variegata). Phylogenetic analysis shows that it is most closely related to the South African shelduck. In captivity, the ruddy shelduck has been known to hybridise with several other members of Tadorna, with several members of the dabbling duck genus Anas, and with the Egyptian goose (Alopochen aegyptiaca). No subspecies are recognised. The generic name Tadorna comes from the French , the common shelduck, and may originally derive from a Celtic word meaning "pied waterfowl". The English name "sheld duck" dates from around 1700 and means the same. ==Description==

, Spiti, Himachal Pradesh The ruddy shelduck grows to a length of and has a wingspan. The male has orange-brown body plumage and a paler, orange-brown head and neck, separated from the body by a narrow black collar. The rump, flight feathers, tail-coverts and tail feathers are black and there are iridescent green speculum feathers on the inner surfaces of the wings. Both upper and lower wing-coverts are white, this feature being particularly noticeable in flight but hardly visible when the bird is at rest. The bill is black and the legs are dark grey. The female is similar but has a rather pale, whitish head and neck and lacks the black collar, and in both sexes, the colouring is variable and fades as the feathers age. The birds moult at the end of the breeding season and the male loses the black collar, but a further partial moult between December and April restores it. Juveniles are similar to the female but are a darker shade of brown. The call is a series of loud, nasal honking notes, it being possible to discern the difference between those produced by the male and the female. The calls are made both on the ground and in the air, and the sounds are variable according to the circumstances in which they are uttered. ==Distribution and habitat==

There are very small resident populations of this species in Northwest Africa and Ethiopia, but the main breeding area of the bird is from southeast Europe across the Palearctic to Lake Baikal, Mongolia, and western China. Eastern populations are mostly migratory, wintering in the Indian subcontinent. This shelduck mostly frequents open locations on inland bodies of water such as lakes, reservoirs and rivers. It is seldom seen in forested areas but does occur in brackish water and saline lagoons. Though more common in the lowlands, it also inhabits higher altitudes and in central Asia is one of the few waterbirds, along with the bar-headed goose (Anser indicus), to be found on lakes at . A stable population exists in Moscow, settling the city parks' ponds alongside the endemic mallards. These birds are feral descendants of escapees from the Moscow Zoo, the population most likely forming after 1948, when the policy of clipping the birds' wings was repealed. Unlike the wild population, these ducks are non-migratory, wintering instead in the non-freezing parts of the city's bodies of water. Population increased from 1990's to 2020's by over 20 times, reaching 3300 by 2025. ==Behaviour==

The ruddy shelduck is a mainly nocturnal bird. It is omnivorous and feeds on grasses, the young shoots of plants, grain and water plants as well as both aquatic and terrestrial invertebrates. On land it grazes on the foliage, in the water it dabbles in the shallows, and at greater depths, it up-ends, but it does not dive. The ruddy shelduck is usually found in pairs or small groups and rarely forms large flocks. However, moulting and wintering gatherings on chosen lakes or slow rivers can be very large. Gatherings of over four thousand birds have been recorded on the Koshi Barrage and in the Koshi Tappu Wildlife Reserve in Nepal, and over ten thousand at Lake Düden in Turkey. The birds arrive at their main breeding locations in central Asia in March and April. There is a strong pair bond between the male and female and it is thought they pair for life. In their breeding quarters, the birds are very aggressive towards their own kind and towards other species. The female in particular approaches intruders with head lowered and neck outstretched, uttering anger calls. If the intruder stands its ground, the female returns to the male and runs round him, inciting him to attack. He may or may not do so. Mating takes place on the water after a brief courtship ritual involving neck stretching, head dipping and tail raising. The nesting site is often far away from water in a hole in a tree or ruined building, a crevice in a cliff, among sand-dunes or in an animal burrow. The nest is constructed by the female using feathers and down and some grasses. A clutch of about eight eggs (range six to twelve) is laid between late April and early June. These have a dull gloss and are creamy-white, averaging . Incubation is done by the female while the male stands in attendance nearby. The eggs hatch after about twenty-eight days and both parents care for the young, which fledge in a further fifty-five days. After breeding the adults moult, losing the power of flight for about a month while they do so. Before moulting they move to large water bodies where they can more easily avoid predation while they are flightless. The family may stay together as a group for some time; the autumn migration starts around September and the young may mature in their second year. North African birds breed about five weeks earlier, and their breeding success is greater in wet summers. ==Status==

, Flagship species of Arjan International Wetland Buddhists regard the ruddy shelduck as sacred as the plumage is the same colour as a lama's robes, and this gives the birds some protection in central and eastern Asia, where the population is thought to be steady or even rising. The Pembo Black-necked Crane Reserve in Tibet is an important wintering area for ruddy shelducks, and here they receive protection. In Europe on the other hand, populations are generally declining as wetlands are drained and the birds are hunted. However, in Europe and Italy the ruddy shelduck is protected, with hunting banned. They are less vulnerable than some other waterfowl because of their adaptability to new habitats such as reservoirs. The ruddy shelduck has a very wide range and an estimated total population size of 170,000 to 225,000 individuals. The overall population trend is unclear as some local populations are increasing while others are decreasing. The bird does not appear to meet the higher criteria necessary to be considered threatened, and the International Union for Conservation of Nature assesses that its conservation status is of least concern. It is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies. ==References==