Purple heron | |
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Adult on a tree, at Vadodara, Gujarat, India | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Pelecaniformes |
Family: | Ardeidae |
Genus: | Ardea |
Species: | A. purpurea |
Binomial name | |
Ardea purpurea Linnaeus, 1766 | |
Range of A. purpurea Breeding Resident Non-breeding |
The purple heron (Ardea purpurea) is a wide-ranging heron species. It breeds in Africa, central and southern Europe, and southern and eastern Palearctic. The Western Palearctic populations migrate between breeding and wintering habitats whereas the African and tropical-Asian populations are primarily sedentary, except for occasional dispersive movements. It is similar in appearance to the more common grey heron but is slightly smaller, more slender and has darker plumage. It is also a more evasive bird, favouring densely vegetated habitats near water, particularly reed beds. It hunts for a range of prey including fish, rodents, frogs and insects, either stalking them or standing waiting in ambush.
Purple herons are colonial breeders and build a bulky nest out of dead reeds or sticks close to the water' edge among reeds or in dense vegetation. About five bluish-green eggs are laid and are incubated by both birds. The young hatch about four weeks later and fledge six weeks after that. The International Union for Conservation of Nature notes that the global population trend is downwards, largely because of the drainage of wetlands, but assesses the purple heron's conservation status as being of "least concern".
The purple heron is a large bird, 78–97 cm (31–38 in) in length with a standing height from 70 to 94 cm (28 to 37 in) and a 120–152 cm (47–60 in) wingspan. [2] [3] However, it is slender for its size, weighing only 0.5 to 1.35 kg (1.1 to 3.0 lb). [4] It is somewhat smaller than the grey heron, from which it can be distinguished by its darker reddish-brown plumage, and, in adults, its darker grey back. Adults have the forehead and the crown of the head black, with a dark stripe down the back of the neck that terminates in a slender, dangling crest. This is shorter than the crest of the grey heron and does not exceed 140 mm (5.5 in). The sides of the head and the neck are buffish chestnut, with dark streaks and lines down either side of the whole the neck. The mantle is oily brown and the upper scapular feathers are elongated but not the lower ones. The rest of the upper parts and the tail are brownish grey. The front of the neck is paler than the sides and there are some elongated feathers at the base of the neck which are streaked with white, chestnut and black. The breast is chestnut brown, with some blackening at the side, and the belly and under-tail coverts are black. The brownish-yellow beak is long, straight and powerful, and is brighter in colour in breeding adults. The iris is yellow and the legs are brown at the front and yellowish behind. [5]
The call is a harsh "frarnk", but is quieter and more high-pitched than that of the grey heron. It is generally a less noisy bird, though similar guttural sounds are heard emanating from the heronry. It is also less robust, and appears somewhat hollow-chested. Its head and neck are more slender and snake-like than the grey heron and its toes much longer. Unlike that bird, it often adopts a posture with its neck extending obliquely, and even nestlings tend to use this stance. [5]
There are three or four subspecies: [6]
The scientific name comes from Latin ardea "heron", and purpureus, "coloured purple". [9]
The purple heron has a mostly palaearctic distribution and breeds in Europe, Asia and Africa. The range of the western race extends from Portugal eastwards across much of central and southern Europe and parts of North Africa as far as Lake Balkhash in Kazakhstan. In Africa, the bird breeds in Senegal, down the east coast of Africa and in Madagascar. The eastern race extends from the Indian Subcontinent, eastwards to eastern China and the Philippines, and northwards to the basins of the Amur River and the Ussuri River at about 49°N. The southern race is restricted to Madagascar, [10] and a small population of purple herons on the Cape Verde Islands is regarded as a separate race by some authorities. [7]
Between August and October, birds of the western population migrate southwards to tropical Africa, returning northwards in March. Purple herons often overshoot their normal range on their return, and are vagrants to northern Europe including Britain. The eastern population is largely resident, though some birds from the northern part of the range fly southwards to Korea, Thailand and Malaysia. The African birds are resident. [10]
The purple heron inhabits marshes, lagoons and lakes surrounded by dense vegetation. It may frequent mangrove swamps on the coast but it usually chooses freshwater habitats, particularly locations with Phragmites reed beds. It also visits mudflats, river banks, ditches and canals. [5] In the Cape Verde Islands, it is more likely to be seen in the open, on arid slopes. [10]
Flight is slow, with the neck retracted and the legs extending a long way behind the tail. This is characteristic of herons and bitterns, and distinguishes them from storks, cranes and spoonbills, which extend their necks in flight. It is a secretive bird, spending less time out in the open than the grey heron and tending to skulk in reed beds. Its long toes mean it can walk on floating vegetation, and it sometimes walks over bushes in the same way, not making any attempt to grip the branches. It seldom perches in trees, preferring more terrestrial sites to rest. [5]
It is most active at dawn and dusk, roosting with other birds in the middle of the day and at night, but increasing its diurnal activity while rearing young. It feeds in shallow water, grabbing its prey with its powerful beak. It will often wait motionless for prey, or slowly stalk its victim. The diet consists mainly of fish, small mammals and amphibians, but nestling birds, snakes, lizards, crustaceans, water snails, insects and spiders are also eaten. Terrestrial beetles are the commonest insect prey, followed by water beetles and aquatic larvae, with grasshoppers, dragonflies, bees and flies also being consumed. [5]
The purple heron usually breeds in colonies but sometimes the nests are solitary. It sometimes associates with other species such as the goliath heron (Ardea goliath) or grey heron at multi-species nesting colonies. The site chosen is generally in reed beds, canebrakes or low bushes close to large lakes or other extensive wetlands. It builds a bulky nest of dead reeds, sticks or whatever is available, carelessly pulling the material together. The eggs are bluish-green, averaging 56 by 45 mm (2.2 by 1.8 in). The clutch is usually four or five eggs, with occasionally seven or eight eggs being laid, though these large clutches may have resulted from two females laying in the same nest. The eggs are laid at intervals of three days, and incubation may begin with the first egg, or start when the clutch is complete. Both parents share the incubation, which lasts between 24 and 28 days, and the care of the young. When an adult brings food, its beak is dragged down by the chicks and it regurgitates food from the crop onto the nest, or the young may take food directly from the beak. The young fledge at about six weeks and become independent at two months. They then disperse widely. [5]
There are estimated to be a total of between 270,000 and 570,000 purple herons in the world and the population is probably decreasing slowly. The International Union for Conservation of Nature has assessed its conservation status as being of "least concern" because the rate of decline is insufficient to justify rating it in a more threatened category. The chief threat the bird faces is drainage and disturbance of its wetland habitats, particularly destruction of the reed beds. [1] The purple heron is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies. [11]
The Eurasian bittern or great bittern is a wading bird in the bittern subfamily (Botaurinae) of the heron family Ardeidae. There are two subspecies, the northern race breeding in parts of Europe and across the Palearctic, as well as on the northern coast of Africa, while the southern race is endemic to parts of southern Africa. It is a secretive bird, seldom seen in the open as it prefers to skulk in reed beds and thick vegetation near water bodies. Its presence is apparent in the spring, when the booming call of the male during the breeding season can be heard. It feeds on fish, small mammals, fledgling birds, amphibians, crustaceans and insects.
Herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 72 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genera Botaurus and Ixobrychus are referred to as bitterns, and, together with the zigzag heron, or zigzag bittern, in the monotypic genus Zebrilus, form a monophyletic group within the Ardeidae. Egrets do not form a biologically distinct group from herons, and tend to be named differently because they are mainly white or have decorative plumes in breeding plumage. Herons, by evolutionary adaptation, have long beaks.
The grey heron is a long-legged wading bird of the heron family, Ardeidae, native throughout temperate Europe and Asia, and also parts of Africa. It is resident in much of its range, but some populations from the more northern parts migrate southwards in autumn. A bird of wetland areas, it can be seen around lakes, rivers, ponds, marshes and on the sea coast. It feeds mostly on aquatic creatures which it catches after standing stationary beside or in the water, or stalking its prey through the shallows.
The great egret (Ardea alba), also known as the common egret, large egret, or great white egret or great white heron, is a large, widely distributed egret. The four subspecies are found in Asia, Africa, the Americas, and southern Europe. Recently, it has also been spreading to more northern areas of Europe. Distributed across most of the tropical and warmer temperate regions of the world, it builds tree nests in colonies close to water.
The little egret is a species of small heron in the family Ardeidae. It is a white bird with a slender black beak, long black legs and, in the western race, yellow feet. As an aquatic bird, it feeds in shallow water and on land, consuming a variety of small creatures. It breeds colonially, often with other species of water birds, making a platform nest of sticks in a tree, bush or reed bed. A clutch of three to five bluish-green eggs is laid and incubated by both parents for about three weeks. The young fledge at about six weeks of age.
The slender-billed gull is a mid-sized gull which breeds very locally around the Mediterranean and the north of the western Indian Ocean on islands and coastal lagoons. Most of the population is somewhat migratory, wintering further south to as far as North Africa and India. A few birds have wandered to western Europe. A vagrant individual was reportedly seen on Antigua, April 24, 1976.
Savi's warbler is a species of Old World warbler in the grass warbler genus Locustella. It breeds in Europe and the western Palearctic. It is migratory, wintering in northern and sub-Saharan Africa.
The black-headed heron is a wading bird of the heron family Ardeidae, common throughout much of sub-Saharan Africa and Madagascar. It is mainly resident, but some west African birds move further north in the rainy season.
The cinnamon bittern or chestnut bittern is a small Old World bittern, breeding in tropical and subtropical Asia from India east to China and Indonesia. It is mainly resident, but some northern birds migrate short distances. This species was formerly placed in the genus Ixobrychus.
The Goliath heron, also known as the giant heron, is a very large wading bird of the heron family, Ardeidae. It is found in sub-Saharan Africa, with smaller, declining numbers in Southwest and South Asia.
The nankeen night heron is a heron that belongs to the genus Nycticorax and the family Ardeidae. Due to its distinctive reddish-brown colour, it is also commonly referred to as the rufous night heron. It is primarily nocturnal and is observed in a broad range of habitats, including forests, meadows, shores, reefs, marshes, grasslands, and swamps. The species is 55 to 65 cm in length, with rich cinnamon upperparts and white underparts. The nankeen night heron has a stable population size, and is classified as a species of least concern by the International Union for Conservation of Nature (IUCN).
Ardea is a genus of herons. These herons are generally large in size, typically 80–100 cm or more in length.
Humblot's heron, also known as the Madagascar heron, is a species of heron. It is commonly found on the north and west coasts of Madagascar but it is also present in the Comoro Islands and Mayotte. Humblot's heron is considered an endangered species due to its declining population. The major threats the heron faces are poaching, habitat destruction, and the invasion of alien species such as the water hyacinth.
The white-necked heron or Pacific heron is a species of heron that is found on most of the Australian continent wherever freshwater habitats exist. It is also found in parts of Indonesia and New Guinea, but is uncommon in Tasmania. The populations of this species in Australia are known to be nomadic like most water birds in Australia, moving from one water source to another, often entering habitats they have not previously occupied, taking advantage of flooding and heavy rain where the surplus of food allows them to breed and raise their young. Irruptive movements may occur when environmental conditions are right in places where the species has been rare or absent.
The cocoi heron is a species of long-legged wading bird in the heron family Ardeidae found across South America. It has predominantly pale grey plumage with a darker grey crest. A carnivore, it hunts fish and crustaceans in shallow water.
Bourne's heron, also known as the Cape Verde heron, Cape Verde purple heron or Santiago heron, or locally in Portuguese as the garça vermelha, is an endangered subspecies of the purple heron that is endemic to the Cape Verde archipelago, in the Atlantic Ocean off the coast of West Africa. It is sometimes considered a full species, Ardea bournei.