Booted eagle

Booted eagle

 "Aquila minuta" redirects here. If based on Brehm (1831), it refers to this bird. The fossil bird described under the same name by Milne-Edwards (1871) is preliminarily known as "Hieraaetus" edwardsi but might belong in Aquila.

The booted eagle (Hieraaetus pennatus, also classified as Aquila pennata) is a medium-sized bird of prey. It is about 46 cm (18 in) in length and has a wingspan of 120 cm (47 in). Like all eagles, it belongs to the family Accipitridae. 

Description

 The booted is a small eagle, comparable to the common buzzard in size though more eagle-like in shape. Males grow to about 510–770 g (1.12–1.70 lb) in weight, with females about 950–1,000 g (2.09–2.20 lb). There are two relatively distinct plumage forms. Pale birds are mainly light grey with a darker head and flight feathers. The other form has mid-brown plumage with dark grey flight feathers.

Breeding and habitat

It breeds in southern Europe, North Africa and across Asia. It is migratory, wintering in Sub-Saharan Africa and South Asia. This eagle lays 1–2 eggs in a tree or crag nest.

Taxonomy

Based on recent genetic research^{[citation needed]} some authors reclassified this species to the genus Aquila, along with some^{[citation needed]} or all other Hieraaetus species. As it is the type species of Hieraaetus, should any of the hawk-eagles have been retained in a distinct genus then a new name for that group would have been necessary.

However, most reference lists currently use H. pennata.

Along with the little eagle, this bird is one of the closest living relatives of the extinct Haast's eagle of New Zealand.

Great white pelican

Description

The great white pelican is a huge bird, with only the Dalmatian pelican averaging larger amongst the pelicans. The wingspan can range from 226 to 360 cm (7.41 to 11.81 ft), with the latter measurement the largest recorded among extant flying animals outside of the great albatrosses. The total length of the great white pelican can range from 140 to 180 cm (55 to 71 in), with the enormous bill comprising 28.9 to 47.1 cm (11.4 to 18.5 in) of that length. Adult males, weigh from 9 to 15 kg (20 to 33 lb), though large races from the Palaearctic are usually around 11 kg (24 lb) with few exceeding 13 kg (29 lb). Females are considerably less bulky and heavy, weighing from 5.4 to 9 kg (12 to 20 lb). Among standard measurements, the wing chord length is 60 to 73 cm (24 to 29 in), the tail is 16 to 21 cm (6.3 to 8.3 in) and the tarsus is 13 to 14.9 cm (5.1 to 5.9 in). The standard measurements from differing areas indicate that pelicans of the species from the Western Palaearctic are somewhat larger in size than ones that reside in Asia and in Africa.
Immature great white pelicans are grey and have dark flight feathers. In flight, it is an elegant soaring bird, with the head held close to and aligned with the body by a downward bend in the neck. In breeding condition the male has pinkish skin on its face and the female has orangey skin. It differs from the Dalmatian pelican by its pure white, rather than greyish-white, plumage, a bare pink facial patch around the eye and pinkish legs. Males are larger than females, and have a long beak that grows in a downwards arc, as opposed to the shorter, straighter beak of the female. The spot-billed pelican of Asia is slightly smaller than the great white, with clear brownish-grey plumage and a paler, duller-colored bill. Similarly, the pink-backed pelican is smaller with brownish-grey plumage, with a light pink to off-grey bill and a pinkish wash to the back.
The great white pelican is well adapted for aquatic life. The short strong legs and webbed feet propel it in water and aid the rather awkward takeoff from the water surface. Once aloft, the long-winged pelicans are powerful fliers, however, and often travel in spectacular V-formation groups.

Distribution and habitat

Great white pelicans are usually birds found in and around shallow, (seasonally or tropical) warm fresh water. Well scattered groups of breeding pelicans occur through Eurasia from the eastern Mediterranean to Vietnam. In Eurasia, fresh or brackish waters may be inhabited and the pelicans may be found in lakes, deltas, lagoons and marshes, usually with dense reed beds nearby for nesting purposes. Additionally, sedentary populations are found year-round in Africa, south of the Sahara Desert although these are patchy. In Africa, great white pelicans occur mainly around freshwater and alkaline lakes and may also be found in coastal, estuarine areas. Beyond reed beds, African pelicans have nested on inselbergs and flat inshore islands off of Banc d'Arguin National Park. Migratory populations are found from Eastern Europe to Kazakhstan during the breeding season. More than 50% of Eurasian great white pelicans breed in the Danube Delta in Romania. They like to stay also in the Lakes near Burgas, Bulgaria and in Srebarna Lake in Bulgaria. The pelicans arrive in the Danube in late March or early April and depart after breeding from September to late November. Wintering locations for European pelicans are not exactly known but wintering birds may occur in northeastern Africa through Iraq to north India, with a particularly large number of breeders from Asia wintering around Pakistan. These are birds that are found mostly in lowlands, though in East Africa and Nepal may be found living at elevations of up to 1,372 m (4,501 ft).

Feeding behavior

The diet of the great white pelican consists mainly of fish. The pelicans leave their roost to feed early in the mornings and may fly over 100 km (62 mi) in search of food, as has been observed in Chad and Mogode, Cameroon. Each pelican needs from 0.9 to 1.4 kg (2.0 to 3.1 lb) of fish every day. This corresponds to around 28,000,000 kg (62,000,000 lb) of fish consumed every year at the largest colony of great white pelicans, on Tanzania's Lake Rukwa, with almost 75,000 birds. Fish targeted are usually fairly large ones, in the 500–600 g (1.1–1.3 lb) weight range, and are taken based on regional abundance. Common carp are preferred in Europe, mullet are preferred in China and Aphanius dispar (a carp) are preferred in India. In Africa, often the commonest cichlids, including many species in the Haplochromis and Tilapia genera, seem to be preferred. The pelican's pouch serves simply as a scoop. As the pelican pushes its bill underwater, the lower bill bows out, creating a large pouch which fills with water and fish. As the bird lifts its head, the pouch contracts, forcing out the water but retaining the fish. A group of 6 to 8 great white pelicans will gather in a horseshoe formation in the water to feed together. They dip their bills in unison, creating a circle of open pouches, ready to trap every fish in the area. Most feeding is cooperative and done in groups, especially in shallow waters where fish schools can be corralled easily, though these pelicans may forage alone as well.
Pelicans are not restricted to fish, however, and are often opportunistic foragers. In some situations they eat chicks of other birds, such as the well documented case off the southwest coast of South Africa. Here, breeding Pelicans from the Dassen Island colony predate chicks weighing up to 2 kg (4.4 lb) from the Cape gannet colony on Malgas Island. Similarly, in Walvis Bay, Namibia the eggs and chicks of Cape cormorants are fed regularly to young pelicans. The local pelican population is so reliant on the cormorants, that when the cormorant species experienced a population decline, the numbers of pelicans appeared to decline as well. Great white pelicans also eat crustaceans, tadpoles and even turtles. They readily accept handouts from humans, and a number of unusual items have been recorded in their diet.
During periods of starvation, pelicans also eat seagulls and ducklings. The gulls are held under water and drowned before being eaten headfirst. A flock of captive great whites in St James' Park, London (see below) is well-known for occasionally eating local pigeons, despite being well-fed.Pelicans will also rob other birds of their prey.

Breeding

The breeding season commences in April or May in temperate zones, is essentially all year around in Africa and runs February through April in India. Large numbers of these pelicans breed together in colonies. The female can lay from 1 to 4 eggs in a clutch, with two being the average. Nest locations are variable. Some populations making stick nests in trees but a majority, including all those who breed in Africa, nest exclusively in scrapes on the ground lined with grass, sticks, feathers and other material. The young are cared for by both parents. The incubation stage lasts for 29 to 36 days. The chicks are naked when they hatch but quickly sprout blackish-brown down. The colony gathers in "pods" around 20 to 25 days after the eggs hatch. The young fledge at 65 to 75 days of age. Around 64% of young successful reach adulthood, with sexual maturity attained at 3 to 4 years of age. White pelicans are often protected from bird-eating raptors by virtue of their own great size, but eagles, especially sympatric Haliaeetus species, may predate their eggs, nestlings and fledgings. Occasionally, pelicans and their young are attacked at their colonies by mammalian carnivores from jackals to lions. As is common in pelicans, the close approach of a large predaceous or unknown mammal, including a human, at a colony will lead the pelican to abandon their nest in self-preservation. Additionally, crocodiles, especially Nile crocodiles in Africa, will readily kill and eat swimming pelicans.