Wildlife · Birds · Long read · 16 min read

Vezhambal: The Hornbills of Kerala, Farmers of the Forest

The great hornbill is Kerala's state bird, a creature of poetry and legend said to wait for the first drop of rain. The truth is even more remarkable: a mother who walls herself into a tree, a father who feeds the family for months, and a bird that plants the forest it lives in. Everything about Kerala's four hornbills, and where to find them around Munnar and the Western Ghats.

By GK Global, Adimali, Munnar · Trails & Tales by GK

You usually hear a great hornbill before you see it. First comes a deep, rushing sound, like a steam engine labouring up a hill or a gust of wind tearing through the treetops. Then, over the canopy of an evergreen valley, a huge black-and-white bird appears, its wings beating slowly, its long tail streaming behind, a massive yellow bill and helmet catching the light. In Malayalam it is the malamuzhakki vezhambal, "the hornbill that makes the mountains echo". It is the state bird of Kerala.

Few birds have entered the imagination of Kerala as deeply as the vezhambal. It appears in poems and film songs, on emblems and in children's stories. It is a symbol of devotion, patience and the longing for rain. And yet its real life, as revealed by decades of research in the forests of the Western Ghats, is in many ways more astonishing than any legend.

A family of giants

Hornbills are a family of about 60 species living in the tropical forests and savannas of Africa and southern Asia. They are named for the large, often curved bill, which in many species is topped by a hollow structure called a casque. Despite its size, the bill is light, made of a thin outer layer of keratin over a honeycomb of bone. Hornbills are found nowhere in the Americas; their place in the rainforests of South America is taken by the unrelated toucans, an example of how evolution can produce similar solutions in different parts of the world.

Hornbills have several features that are unique or unusual among birds. The first two vertebrae of the neck are fused together, which is thought to help support the weight of the bill. They have long, thick eyelashes, which are actually modified feathers. And they lack the dense small feathers that cover the underside of the wings in most birds, which is why air rushing between the flight feathers produces the famous loud whooshing sound.

Kerala's four hornbills

Great hornbill: malamuzhakki vezhambal

The great hornbill (Buceros bicornis) is one of the largest hornbills in the world: up to 1.3 m long from bill to tail, with a wingspan of around 1.5 m, and weighing 2 to 4 kg. Its plumage is black and white, with a broad black band across white wings and a white tail crossed by a black band. The huge bill and casque are bright yellow and black. The colour is not entirely natural: the birds rub a yellow-orange oil from the preen gland at the base of the tail onto their bill, casque and wing feathers, like make-up.

Males and females can be told apart by their eyes. The male has a red eye and the underside of his casque is black; the female, which is smaller, has a bluish-white eye and a reddish patch at the back of the casque.

Great hornbills live in tall, mature evergreen and moist deciduous forest, from the plains up to about 1,500 m. Outside India, they range through the Himalayan foothills and northeast India to Southeast Asia and Sumatra. In the Western Ghats they are found in the larger forest tracts from Karnataka and Goa south to the hills of southern Kerala and Tamil Nadu. The species has been listed as Vulnerable on the IUCN Red List since 2018.

Malabar grey hornbill: kozhi vezhambal

The Malabar grey hornbill (Ocyceros griseus) is the smallest hornbill in Asia, about 45–58 cm long, grey and brown with a white stripe above the eye, a cinnamon patch under the tail and a curved bill with no casque. The male's bill is reddish with a yellow tip; the female's is mostly yellow. It is endemic to the Western Ghats, found nowhere else in the world.

It is the hornbill most often seen in Kerala, in pairs or small groups in forests and in the rubber, arecanut, coffee and cardamom plantations around them, from about 50 m to 1,500 m. It is famous for its loud, cackling, laughing calls, which resemble the cackling of a hen (kozhi), possibly the origin of its Malayalam name. Although it is still widespread, it depends on large trees for nesting and has declined with the loss of forest; it is now listed as Vulnerable.

Malabar pied hornbill: pandan vezhambal

The Malabar pied hornbill (Anthracoceros coronatus) is a large black-and-white hornbill, about 65 cm long and around 1 kg in weight, with a yellow bill topped by a large, mainly black casque. It is found in parts of central and eastern India, along the Western Ghats and the west coast, and in Sri Lanka. In Kerala it is a bird of the low-altitude riverside forests, which have been among the most heavily cleared and dammed habitats in the state. It eats figs and other fruits, and also hunts small animals, including lizards, small birds and their eggs. It is listed as Near Threatened.

Indian grey hornbill

The Indian grey hornbill (Ocyceros birostris), with a small black casque, is a widespread bird of open woodland, dry forest and even city parks across much of India. In Kerala it is recorded in many districts, usually in more open and drier country than the Malabar grey hornbill, and is easily confused with it. It is listed as Least Concern.

Remarkably, the riverine forests of Athirappilly–Vazhachal in Thrissur district are said to be the only place in the Western Ghats where all four of Kerala's hornbill species can be seen.

The farmers of the forest

Hornbills are mainly fruit-eaters. Figs, which ripen at different times throughout the year, are their staple food; they also eat the fruits of nutmegs, laurels, custard-apples and many other forest trees, as well as insects, lizards, small birds, eggs and small mammals, especially when feeding chicks.

Because they swallow fruits whole and fly long distances before regurgitating or passing the seeds, hornbills are among the most important seed dispersers in Asian forests. Many large-seeded trees depend on hornbills, and on few other animals, to carry their seeds away from the parent tree. Hornbills have been called the "farmers of the forest". Where they disappear, the forest itself slowly changes.

Hornbills obtain most of the water they need from the fruit they eat and are rarely seen drinking. This may help to explain one of the most beautiful legends about them.

The bird that waits for rain

In Malayalam poetry, songs and popular imagination, the vezhambal is the bird that waits for rain. In the heat of summer, it is said, it sits gazing at the sky with its bill open, waiting to catch the first drops of the monsoon, for it will drink no other water. The image has become a symbol of longing and patient devotion, and of the deep connection between the people of Kerala and the monsoon.

The legend has roots in an older Indian tradition about the chataka, a bird in Sanskrit poetry said to drink only raindrops. Ornithologists usually identify the chataka with the pied cuckoo, whose arrival heralds the monsoon. In Kerala, the image passed to the hornbill. Science does not support the idea that hornbills drink only rain, but it is true that they rarely drink at all, getting their water from fruit; and their breeding season is closely tied to the coming of the rains, when fruit becomes abundant for the growing chicks.

A life sealed in a tree

The breeding of hornbills is one of the most extraordinary stories in the bird world, and it is the source of the vezhambal's reputation for devotion and loyalty.

1. Choosing a home. Hornbills cannot dig their own nests. They depend on natural hollows in large, old trees, often formed where a branch has broken off and the wood has rotted. Great hornbills need very large trees, usually tall evergreen or semi-evergreen trees with a trunk wide enough to hold a large cavity high above the ground. Pairs often return to the same nest tree year after year, sometimes for decades.
2. Walling herself in. In the Western Ghats, the breeding season usually runs from about January to May. When the female is ready to lay, she enters the hollow and, with the help of the male, seals the entrance with a plaster made mainly of her own droppings, mixed with mud, fruit pulp and wood. She leaves only a narrow vertical slit through which the male can pass food.
3. The moult. Inside the nest, the female sheds her flight and tail feathers, all at once, and uses them to line the nest. For weeks she cannot fly at all, and depends completely on her mate.
4. Eggs and chicks. The great hornbill lays one or two white eggs, which hatch after about 38–40 days of incubation; Malabar grey and pied hornbills may lay two to four. Usually only one great hornbill chick survives.
5. The devoted father. Throughout this time, the male feeds the female and then the chick, bringing food many times a day. He carries fruits in his throat and regurgitates them one by one through the slit. A male Malabar grey hornbill announces his arrival by tapping on the tree. If the male is killed, the female and chick may starve.
6. Breaking out. In many hornbills, the female breaks out when the chick is about half-grown, and then, with the chick, rebuilds the wall. Both parents then feed the chick until it is ready to leave the nest. In the great hornbill, the whole nesting cycle, from sealing to fledging, lasts around four months.

Because the female and chick depend so completely on the male, and because pairs often stay together and return to the same nest year after year, hornbills have come to symbolise faithfulness in many cultures. Scientists describe them as forming long-term pair bonds. The image of the noble, loyal vezhambal is, in this sense, rooted in real behaviour.

Hornbills are long-lived. Great hornbills have lived for nearly 50 years in captivity. But they breed slowly, raising at most one or two chicks a year, and only if the nest tree survives, the male survives and fruit is plentiful. This makes them very vulnerable to any increase in deaths among adults.

Hornbills around Munnar and the Western Ghats

Munnar itself, at around 1,600 m and surrounded by tea, is too high and too open for great hornbills. But the forests on the slopes below are hornbill country. On the lower slopes and valleys on the way to Munnar from Kochi, around Adimali, Mankulam, Neriamangalam and the Idamalayar and Pooyamkutty forests, the cackling call of the Malabar grey hornbill is a familiar sound, and great hornbills can be seen crossing the evergreen valleys. Further down, the Thattekkad Bird Sanctuary on the Periyar river is one of the best places in Kerala to see the Malabar grey, the Malabar pied and, with luck, the great hornbill.

Across the Western Ghats, important hornbill areas include:

• Athirappilly–Vazhachal and Sholayar (Thrissur): riverine and evergreen forests with all four of Kerala's hornbills.
• The Anamalai Hills and Valparai (Tamil Nadu), just north of Munnar: long-term research by the Nature Conservation Foundation on great hornbills nesting in rainforest fragments among tea estates.
• Parambikulam, Nelliyampathy and Silent Valley (Palakkad).
• Periyar Tiger Reserve (Idukki).
• Dandeli and Anshi (Karnataka), where great hornbills gather to roost in large numbers.

Great hornbills occasionally wander far from the forest. In 2025, a great hornbill surprised residents by turning up at Nayarambalam on Vypin island near Kochi, the first time the species had been recorded there.

Threats

• Loss of nest trees. The single greatest threat. Selective logging removes exactly the large, old, hollow trees that hornbills need, and such trees take a century or more to replace. Clearing of forest for plantations, roads and dams has removed many more.
• Loss of riverine forest. Low-altitude forests along rivers, the home of the Malabar pied hornbill, have been flooded by reservoirs, cleared for farms and settlements, and fragmented. Proposals for new dams on rivers such as the Chalakudy at Athirappilly have been opposed by conservationists partly because they would submerge hornbill habitat.
• Hunting. Hornbills have been hunted for their meat, their fat and oil (believed in some places to have medicinal value), their casques and their feathers. Killing a male during the breeding season dooms the female and chick sealed in the nest.
• Fragmentation and climate. Small forest fragments may not hold enough fruit trees through the year, and changes in the timing of rain and fruiting could affect breeding.

Conservation: reasons for hope

At Vazhachal, a community programme involving the indigenous Kadar people, the forest department and researchers led by Dr K. H. Amitha Bachan of the Western Ghats Hornbill Foundation has monitored hornbill nest trees since 2005. Kadar "hornbill watchers" guard the nests, campaigns have reduced hunting, and abandoned nests have been restored. When the work began, only four nesting trees of the Malabar pied hornbill were known in the area; later, the population had grown to around 100 birds using 12 nesting sites.

In the Anamalai Hills, researchers have monitored great hornbill nests and worked with tea estates to protect and restore rainforest fragments. In Arunachal Pradesh, the other state that has the great hornbill as its state bird, a nest adoption programme at Pakke Tiger Reserve pays local people to protect nests, a model that has inspired similar efforts elsewhere. All of Kerala's hornbills are protected under the Wild Life (Protection) Act.

The lesson from all these programmes is simple: protect the big trees, protect the birds during the breeding season, and work with the people who live in the forest.

Seeing hornbills responsibly

The vezhambal is a fitting symbol for Kerala. Like the state itself, it depends on the monsoon and the forest. Its survival depends on protecting the great trees of the Western Ghats, and on the care of the people who share its home. (Read also our articles on the birds of Munnar and the Western Ghats and Thattekkad Bird Sanctuary.)