Black-Shouldered Kite

## Description

The black-shouldered kite (Elanus axillaris ), also known as the Australian black-shouldered kite, is a small raptor found in open habitat throughout Australia. It resembles similar species found in Africa, Eurasia and North America, including the black-winged kite, a species that has in the past also been called "black-shouldered kite". Measuring around 35 cm (14 in) in length with a wingspan of 80–100 cm (31–39 in), the adult black-shouldered kite has predominantly grey-white plumage and prominent black markings above its red eyes. It gains its name from the black patches on its wings. The primary call is a clear whistle, uttered in flight and while hovering. It can be confused with the related letter-winged kite in Australia, which is distinguished by the striking black markings under its wings.

The species forms monogamous pairs, breeding between August and January. The birds engage in aerial courtship displays which involve high circling flight and ritualised feeding mid-air. Three or four eggs are laid and incubated for around thirty days. Chicks are fully fledged within five weeks of hatching and can hunt for mice within a week of leaving the nest. Juveniles disperse widely from the home territory. The black-shouldered kite hunts in open grasslands, searching for its prey by hovering and systematically scanning the ground. It mainly eats small rodents, particularly the introduced house mouse, and has benefitted from the modification of the Australian landscape by agriculture. It is rated as least concern on the International Union for Conservation of Nature (IUCN)'s Red List of "Endangered species."

## Appearance

Black-shouldered kites are small graceful raptors found in open habitat throughout Australia. Males and females have similar plumage. Their crown, neck, and upperparts are pale grey, while the head and underparts are white. A black comma-shaped marking lies in front of and stretches over and behind the eye, which is deep red and surrounded by a black orbital ring. The leading edge of the outer wing is black. When perched, this gives the species its prominent black "shoulders". The legs and feet are also yellow or golden-yellow, and the feet have three toes facing forwards and one toe facing backwards.

## Distribution

Black-shouldered kites are found throughout Australia. They may be sedentary or nomadic and are generally found in open grasslands or valleys where there are scattered clumps of trees. They also forage over pastures, cereal or vegetable crops and vineyards, often focusing on areas that have been recently harvested or ploughed and hence rendering prey more exposed. In urban areas, they are encountered on the edge of towns on wasteland, irregularly mown areas, sports fields, golf courses or grassy roadside verges. Black-shouldered kites also hunt over coastal dunes and drier marshland but avoid areas with dense cover such as forest as well as the bare or rocky ground.

## Behavior

Black-shouldered kites usually hunt singly or in pairs; where food is plentiful they occur in small family groups and can be loosely gregarious, with up to 70 birds reported feeding together during a mouse plague. During the night the birds usually roost communally. However, when food is not abundant, Black-shouldered kites are territorial. They practice "tail flicking" which is thought to be a possible territorial display; ''tail flicking'' is a behavior where, on landing, the kite flicks up and lowers its tail and this movement is repeated persistently. Black-shouldered kites prefer to hunt during the day, particularly in the early morning and mid to late afternoon. They hunt by quartering grasslands for small creatures. This can be from a perch, but more often by hovering in mid-air. Typically, a kite hovers 10 to 12 m (35 to 40 ft) above a particular spot. When hunting from a perch, a dead tree is the preferred platform. When a mouse or other prey is spotted, the kite drops silently onto it, feet-first with wings raised high. Prey is seized in the talons and about 75% of attacks are successful. Prey can either be eaten in flight or carried back to a perch. Black-shouldered kites are generally silent, except in the breeding season when their calls, though weak, can be persistent. They primarily utter a clear whistled chee, chee, chee call in flight and while hovering, or a hoarse wheezing skree-ah when perched. A short high whistle is the primary contact call between a pair, while a harsh scraping call is the most common call used by the female and large young, and brooding females call to their young with a deep, soft, frog-like croak.

## Diet

Black-shouldered kites are carnivores. They feed on grasshoppers, rats, small reptiles, birds, and even (very rarely) rabbits. However, mice and other mouse-sized mammals make up over 90% of their diet.

## Reproduction

Black-shouldered kites form monogamous pairs. Aerial courtship displays involve single and mutual high circling flight, and the male may fly around with wings held high rapidly fluttering, known as flutter-flight. Courting males dive at the female, feeding her in mid-flight. The female grabs food from the male's talons with hers while flipping upside-down. They may lock talons and tumble downwards in a ritualized version of grappling, but release just before landing. All courtship displays are accompanied by constant calling. The breeding season is usually August to January but is responsive to mice populations, and some pairs breed twice in a good season. Both sexes collect material for the nest but the female alone builds it. The nest is a large untidy shallow cup of sticks and takes anywhere from 2 to 6 weeks to be built. It is constructed of thin twigs and is lined with green leaves and felted fur. It is generally located in the canopy of an isolated or exposed tree in an open country, elevated 5 to 20 m (16 to 66 ft) or more above the ground. The female lays 3-4 dull white eggs of a tapered oval shape and with red-brown blotches. She incubates the eggs for 30 days and when the chicks hatch they are helpless but have soft down covering their body. For the first two weeks or so the female broods the chicks constantly, both day and night. The nestling period lasts around 36 days, and the post-fledging period at least 36 days with parental feeding for at least 22 days. When the chicks are older both parents take it in turns to feed them. The young are fully-fledged and are ready to fly in 5 weeks. Within a week of leaving the nest, the young birds are capable of hunting for mice on their own.

## Population

### Population threats

There are no major threats facing Black-shouldered kites at present. However, populations in areas with high sheep and rabbit numbers may decline, as these animals compact the soil and reduce the available habitat for mice which are the main prey item for the kites.

### Population number

According to the IUCN Red List, the total population size of the Black-shouldered kite is more than 100,000 individuals. The national population consists of less than 10,000 breeding pairs in China and less than 100 breeding pairs in Taiwan. Currently, this species is classified as Least Concern (LC) and its numbers today are increasing.

### Ecological niche

Black-shouldered kites have become a specialist predator of the introduced house mouse, often following outbreaks of mouse plagues in rural areas. Their influence on mouse populations is probably significant; adults take two or three mice a day each if they can, around a thousand mice a year. On one occasion, a male was observed bringing no less than 14 mice to a nest of well-advanced fledglings within an hour.

## Fun Facts for Kids

The Black-shouldered kite is often confused with its close relative Letter-winged kite in Australia; the latter can be distinguished by the striking black markings under its wings.

Black-shouldered kites have their favored feeding perch which can be easily spotted as beneath them accumulate piles of pellets or castings.

Black-shouldered kites spiral into the wind like a kestrel. They soar with v-shaped up-curved wings, the primaries slightly spread and the tail widely fanned, giving the tail a squarer appearance and visible 'fingers' on the wings. Their flight pattern has been described as 'winnowing' with soft steady beats interspersed with long glides on angled wings. These graceful birds can most often be seen hovering with wings curved and tail pointing down.

In southwestern Australia, the Black-shouldered kite has become one of the most commonly recorded raptors in the wheatbelt and has benefited from the large numbers of mice that live near grain farms.

## References

https://animalia.bio/black-shouldered-kite