Birds,  Fauna,  Nature

The ‘tantalising’ painted storks

The word ‘tantalise’ means ‘desirable but just out of reach’. This word is derived from the Greek mythological figure Tantalus. As the legend goes, Tantalus is a son of Zeus who is an evil doer. In one story he steals ambrosia from the Gods. In another macabre tale, he cuts up his son and serves him in a banquet. As punishment, he was made to stand in a pool of water beneath a fruit tree with low branches. Whenever he reached for the fruit, the branches moved higher eluding his grasp. Whenever he bent down to drink, the water always receded.

What has this story got to do with the beautiful painted storks? In the past, this bird species had been placed in genera Tantalus and Pseudotantalus. Perhaps some scientist with an interest in mythology was intrigued by how these beautiful birds spent long hours foraging in lakes, pools and ponds. However this terminology has now changed and these birds have been placed in the genus Mycteria along with other wood storks, due to their similar bill structure.

Painted storks are essentially waders and it is common to see them foraging in flocks in shallow waters of irrigation canals, fields, ponds, rivers or lakes. They are found in fresh water wetlands in the Indian subcontinent (mostly in India and Sri Lanka), as well as in Southeast Asia.

What makes them stand out are their distinctive pink tertial feathers. They have bare and orange or reddish heads. A distinctive black band with white scaly markings runs across the breast. This black band continues into the underwing coverts and the white tips of the black coverts give it the appearance of white stripes running across the underwing. The rest of the body is white in adults. The legs are yellowish to red. But they have a habit of defecating on their legs (called urohidrosis) and this can make their legs appear white sometimes. Like all storks they fly with outstretched necks.

Painted storks are large birds standing about 93–102 cm tall and weighing 2–3.5 kg . They have heavy yellow beaks. The bird does not hold its bill completely horizontal to the ground while standing, thus giving an impression that it is strongly decurved. Actually, the bill is straight for most of its length, but approximately 18.5 cm from the mouth there is a downward decurvature of approximately 11°.  The down-turned tips of the beaks are similar to those of ibises. However they are rather quiet birds compared to the ibises. While they are usually silent, you might catch them making low moaning sounds during nesting.

They have a typical style of preying on fish which is called tactile foraging. As they wade, they stir the water with their feet, causing the fish to surface. They immerse their partially open beaks in water, with their eyes above the water mark, and sweep the bills from side to side. As the water is often hazy or muddy, they cannot see the fish. However when they sense the presence of fish by touch, they quickly snap up their prey. When they do this while walking forward this technique is called active tactolocation. At other times, the stork might prefer to stand still, and wait for fish to make contact with its mandibles. This is referred to as passive tactolocation.

Painted storks tend to nest in colonies. Their nesting colonies often become centres of tourist attraction due to their large size and pretty colours. They breed on trees, either in mixed colonies along with other water birds, or by themselves. Their breeding season begins in winter shortly after the monsoons. In northern India, the breeding season begins in mid-August, while in southern India the nest initiation begins around October and continues until February or even April. In storks, breeding is limited by food availability.

A colony of painted storks, Pune, December 2017. Photo by Anvita Paranjpe

Painted storks are a near threatened species. This species is thought to be undergoing a moderately rapid population decline owing primarily to hunting, land encroachment, wetland drainage and pollution. It will be a pity should this stunningly beautiful specimen of the avian species be wiped off the face of the earth, thanks to our selfish destruction of the environment.

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