About Ardea purpurea Linnaeus, 1766
The purple heron (Ardea purpurea Linnaeus, 1766) is a large but slender heron species. It measures 78–97 cm (31–38 in) in length, has a standing height of 70 to 94 cm (28 to 37 in), a wingspan of 120–152 cm (47–60 in), and weighs only 0.5 to 1.35 kg (1.1 to 3.0 lb). It is somewhat smaller than the grey heron, and can be distinguished from that species by its darker reddish-brown plumage; adult purple herons also have a darker grey back. Adults have black on the forehead and crown of the head, with a dark stripe running down the back of the neck that ends in a slender, dangling crest. This crest is shorter than the grey heron's, and does not exceed 140 mm (5.5 in). The sides of the head and neck are buffish chestnut, with dark streaks and lines running down both sides of the full length of the neck. The mantle is oily brown, and the upper scapular feathers are elongated, while the lower scapular feathers are not. The rest of the bird's 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 streaked with white, chestnut and black. The breast is chestnut brown, with some blackening along the side, while the belly and under-tail coverts are black. The long, straight, powerful beak is brownish-yellow, and is brighter in color in breeding adults. The iris is yellow, and the legs are brown at the front and yellowish behind. The purple heron's call is a harsh "frarnk", which is quieter and higher-pitched than the grey heron's call. It is generally a less noisy bird, though similar guttural sounds can be heard coming from heronries. It is less robust than the grey heron, and appears somewhat hollow-chested. Its head and neck are more slender and snake-like than the grey heron's, and its toes are much longer. Unlike the grey heron, it often holds a posture with its neck extended obliquely, and even nestlings tend to use this stance. The purple heron has a mostly Palearctic distribution, and breeds in Europe, Asia and Africa. The range of the western race extends from Portugal east across much of central and southern Europe and parts of North Africa as far east as Lake Balkhash in Kazakhstan. In Africa, the species breeds in Senegal, along the east coast of Africa, and in Madagascar. The eastern race extends from the Indian subcontinent, east to eastern China and the Philippines, and north to the basins of the Amur River and Ussuri River at around 49°N. The southern race is restricted to Madagascar, and a small population of purple herons on the Cape Verde Islands is considered a separate race by some authorities. Between August and October, western population birds migrate south to tropical Africa, returning north in March. Purple herons often overshoot their normal range on their return migration, and are vagrants to northern Europe including Britain. They have also been recorded in French Guiana, Barbados, Brazil, and Trinidad and Tobago. The eastern population is largely resident, though some birds from the northern part of the range fly south to Korea, Thailand and Malaysia. African purple herons are resident. The purple heron lives in marshes, lagoons and lakes surrounded by dense vegetation. It may use coastal mangrove swamps, but it usually prefers freshwater habitats, especially locations with Phragmites reed beds. It also visits mudflats, river banks, ditches and canals. On the Cape Verde Islands, it is more often seen in the open, on arid slopes. When in flight, the purple heron moves slowly, with its neck retracted and its legs extending far behind the tail. This is a characteristic feature of herons and bitterns, which distinguishes them from storks, cranes and spoonbills, which extend their necks during flight. It is a secretive bird that spends less time in open areas than the grey heron, and tends to hide in reed beds. Its long toes let it walk on floating vegetation, and it sometimes walks over bushes the same way, without attempting to grip the branches. It seldom perches in trees, preferring more terrestrial sites for resting. It is most active at dawn and dusk, roosting with other birds in the middle of the day and at night, but becomes more active during the day when rearing young. It feeds in shallow water, catching prey with its powerful beak. It often waits motionless for prey, or slowly stalks its target. Its diet consists mainly of fish, small mammals and amphibians, but it also eats nestling birds, snakes, lizards, crustaceans, water snails, insects and spiders. Terrestrial beetles are the most common insect prey, followed by water beetles and aquatic larvae; grasshoppers, dragonflies, bees and flies are also consumed. The purple heron usually breeds in colonies, but sometimes nests are solitary. It sometimes associates with other species such as the goliath heron (Ardea goliath) or grey heron in multi-species nesting colonies. Nests are generally built in reed beds, canebrakes or low bushes close to large lakes or other extensive wetlands. It builds a bulky nest from dead reeds, sticks or whatever available material is nearby, pulling the material together carelessly. The eggs are bluish-green, and average 56 by 45 mm (2.2 by 1.8 in). Clutches usually contain four or five eggs; occasionally seven or eight eggs are laid, though these large clutches may come from two females laying in the same nest. Eggs are laid at three-day intervals, and incubation may start with the first egg or begin once the clutch is complete. Both parents share incubation, which lasts between 24 and 28 days, and share care of the young. When an adult brings food, chicks pull down the adult's beak, and the adult regurgitates food from its crop onto the nest, or the young may take food directly from the adult's beak. The young fledge at about six weeks old and become independent at two months, after which they disperse widely.
