Chinese Pond Heron
Willem is a wildlife artist based in South Africa. He says "My aim is simply to express the beauty and wonder that is in Nature, and to heighten people's appreciation of plants, animals and the wilderness. Not everything I paint is African! Though I've never been there, I'm also fascinated by Asia and I've done paintings of Asian rhinos and birds as well. I may in future do some of European, Australian and American species too. I'm fascinated by wild things from all over the world! I mainly paint in watercolours. . . but actually many media including 'digital' paintings with the computer!"
Most of my Colours of Wildlife subjects are from South Africa, since I live here after all and these are the things I'm seeing around me. This time, however, I am bringing you a little birdie from somewhere else! This is the Chinese Pond Heron, Ardeola bacchus. I painted this because I found a photo of it with a very nice pose and I also like the foreground and background, perfectly illustrating the wetland habitat of this small heron. It is a close relative of the Squacco Heron, Ardeola ralloides, a species I do encounter here from time to time. The Chinese Pond Heron is similar in size but is more richly coloured. The scientific name 'Ardeola' means 'little heron', and 'bacchus' refers to the Greek god of wine, perhaps a reference to the wine-red plumage of its neck.
This heron is part of what is sometimes called a superspecies. This is a complex consisting of two or more species that are nevertheless very closely related, and are usually divided up between different geographic regions. The Chinese Pond Heron forms a superspecies complex with the Indian Pond Heron, Ardeola grayi, and the Javan Pond Heron, Ardeola speciosa. The Indian Pond Heron occurs, as you might gather, in India – and so, to the west of the Chinese species, while the Javan Pond Heron occurs to the south, Java being one of the islands of Indonesia. Actually the Javan Pond Heron also occurs on other islands and even on part of the Asian mainland, and the Indian Pond Heron also occurs in Burma, Bangladesh and Sri Lanka. But what is important is that there is no overlap between the breeding ranges of these different species: they replace each other geographically. They are so closely related that if they did overlap, they would interbreed and thus form even more intermediates. But this would be an unstable situation; over thousands of generations this interbreeding would result in a homogenous species. So the fact that the three forms are distinct from each other means that for a long period of time they did not interbreed. Interestingly they do often overlap outside of the breeding season, this and other Ardeola-species being somewhat nomadic or migratory. Chinese pond herons are sometimes seen far outside their normal range; they've even turned up in Alaska!
The Chinese Pond Heron breeds mostly in southern and eastern China, but also in a bit of Burma and Japan. Outside the breeding season it occurs more to the south, including Indonesia. It inhabits a variety of wetlands both inland and at the coast. They prefer shallow water, since they are much smaller (reaching a length of 47 cm/19") and shorter-legged than the larger herons. Rice paddies suit them well. They will wade in deeply sometimes, or perch on a stump or rock at the edge or emerging from the water. While usually appearing rather compact, this heron has a deceptively long neck, which it can dart forward rapidly to catch its prey. The neck can be stretched out so the heron can look over tall vegetation, but also be retracted to keep it concealed while it stalks its prey. It eats fish, frogs, insects, crustaceans and other aquatic invertebrates. They are opportunistic hunters, though, and have also been seen catching other birds! These herons usually hunt in the morning or afternoon, resting during mid-day in roosts along with other wetland birds.
During most of the year the pond herons are rather plainer than the one in my picture: they are mostly whitish with dull brown streaks. Then they do indeed look very much like the Squacco Herons. In the breeding season, which is spring to summer, they grow a new suit of feathery finery, rich reddish-brown on the head, neck and lower chest, with slaty-blue, fine, hair-like plumes over the back, while the wings and belly remain white.
The all-white wings are rather hidden beneath the back plumes at rest, but are very striking in flight.
They breed mixed in with other herons and waterbirds in large colonies, making small, untidy platform-nests of sticks in trees and bushes. They prefer to nest quite high, often 10 m or more above ground level. They sometimes line their nests with grass and leaves.
Sadly, the courtship behavior of this elegant heron has not yet been described. But surely it should involve the showy, long plumes on the neck and back, and will probably feature some raucous calling as well! Its voice is similar to that of the Squacco heron – a harsh croak.
The female herons lay 2 to 8 eggs per clutch. The eggs are greenish blue. The parents feed the chicks by regurgitation into their open mouths. The chicks fledge in a month, and are independent by the age of 36 days. These herons often raise two broods per year.