SANGGUA, West Kalimantan, Indonesia -- Made from the solidified saliva of white-nest swiftlets, the edible bird's nest has been a part of Chinese cookery for 1,200 years. Soaked in boiling water to make a hearty gelatinous soup with broth or sugar, the flavorless ingredient is prized by connoisseurs for its alleged health benefits.
"The elixir is reputed to possess medicinal properties that nourish and vitalize the organ systems of the body, help increase energy and metabolism, dissolve phlegm, improve the voice, relieve gastric problems, aid kidney function, enhance the complexion, alleviate asthma, suppress cough, cure tuberculosis, strengthen the immune system and improve concentration," wrote Craig Thorburn, an environmental scientist from Australia in his research paper, "The Edible Birds' Nest Boom in Indonesia and South-east Asia." Bird's nest soup is also considered an aphrodisiac by some and an infant superfood by others that helps babies grow tall and smart.
Edible bird's nests were traditionally sourced from dark damp dark caves in tropical regions of Southeast Asia by daredevil climbers who balanced on flimsy bamboo ladders and scaffolding up to 60 meters high. The risk was great but so were the rewards, with each cup-shaped nest selling for the equivalent of hundreds of dollars in today's money. The sky-high prices made edible bird's nest one of the world's most valuable animal products and earned it the moniker, "the Caviar of the East."
But in the postwar years when demand from middle- and upper-class Chinese consumers soared, swiftlets couldn't compete with harvesters, and between 1957 and 1997 their populations plummeted as much as 88%. "Harvesters would often try and collect as many nests as they could, regardless of whether they were fully formed, and they would just take them repeatedly," said Creighton Connolly, a senior lecturer in geography at the University of Lincoln.
To meet demand, entrepreneurs in the 1990s began growing swiftlet nests indoors in multistory buildings constructed of sand, chalk and cement to replicate the facade of caves with small openings for swiftlets to enter.
Purpose-built factories have popped up like mushrooms in Malaysia, Thailand, Vietnam and, most recently, in Cambodia, though the vast majority are found in Indonesia. The country exported 1,200 tons of edible bird's nests last year, according to the Indonesian Central Statistics Agency. Java was originally the epicenter of the production but cheaper land prices and more robust white-nest swiftlet populations have seen the province of West Kalimantan, on the Indonesian section of Borneo Island, emerge as the new global center of bird's nest factories.
Siku, who like many Indonesians goes by only one name, is a bird's nest producer in Sanggua, a small inland city in West Kalimantan. He built a bird's nest factory on his rooftop in 2017 -- a single-story edifice with soaring ceilings and wooden beams where swiftlets like to build their nests. The birds are neither bred nor captured. Rather, they are attracted by high-frequency bird calls emitted by dozens of small speakers set on the walls and beams.
"Lots of my neighbors built birdhouses and made money so I wanted to do the same," Siku said. "It took me three months to build and cost $7,000. In the first year, the building attracted relatively few birds. But in the second year many more came. They enter the house at about 4 p.m. and stay all night. In the morning the birds go out to find food, so I don't need to feed them."
Siku produces about a kilogram of edible bird's nests per month, earning 10 million rupiah (nearly $690) -- more than four times Indonesia's average monthly salary of $170 per month, according to CEIC Data. "It's been very profitable," he said. "I recouped the cost of my investment very quickly."
Siku sells most of what he produces to Tommy Chen, a savvy 26-year-old second-generation bird's nest trader from an Indonesian family of Chinese origin on Batam Island who grew up eating birds nest porridge at home. "It's a very special dish," he said. "We cook it with sugar and pandan leaves and then put it in the refrigerator to make a jelly. It tastes a little sweet."
Every month Chen buys about 300 kg of the nests in West Kalimantan. "It's not an easy business because many people are now trying to buy nests in West Kalimantan," he said. "In the [capital city] Pontianak it costs about $850 for one kilogram, though if I go to villages, I pay 10% to 20% less."
From Pontianak, Chen airfreights the valuable cargo to Jakarta, where his uncle owns an edible bird's nest processing plant. There, excrement, bird food, and other impurities are painstakingly removed from the nests by hand. "Some people clean it with chemicals but this is not good for human consumption," Chan said, adding that the cleaner and whiter the product, the higher its value. "After cleaning we send it to China and sell it to wholesalers or directly to restaurants. There are four different grades, A, B, C and D. The prices vary from $1,400 to $2,100 per kilogram.
Chan says his family cannot keep up with demand. "It is becoming more and more popular over in China. During the Chinese New Year, people give mooncakes as presents. But the wealthy people always give bird's nest from Indonesia, because it's considered the best. In restaurants, bird's nest soup sells for around 200 yuan -- $30 per bowl."
Surprisingly, there are no dedicated bird's nest restaurants in West Kalimantan and only a handful in other parts of the county -- principally in cities with large Chinese communities like Surabaya in Java and Medan in Sumatra.
Bird's nest soup is also sold at high-end Chinese restaurants in Indonesia, like Ah Yat Abalone in the Rimba Jimbaran luxury hotel on the resort island of Bali. There, Lin Chee Keong, the Malaysian-Chinese chef de cuisine, prepares the dish in four ways: with chicken, pork, pumpkin or rock sugar. "The secret to making good bird's nest soup is the stock," he said. "For the pork flavored soup, I use pork legs from China and spend five to eight hours cooking to create a rich high-quality flavor."
Each bowl comes with only 40 grams of bird's nest but costs $55. Keong says he normally sells about 10 bowls a day and that sales have only dropped marginally during the pandemic despite the absence of the million-plus Chinese tourists that normally visit the island every year.
"Bird's nest soup is a kind of tonic food that nourishes the lung and relieves coughs," he said. "Many local people are now trying this health-preserving recipe."