Birds’ Nest which was primarily known as Swallow Nest in the early days was first found during the Tang Dynasty (A.D. 618-907) back in China nearly 1500 years ago. According to much historical data, in the classical Chinese Medicine Book about healthy food, swallow nests were imported into China from the Southeast Asian region dated back more than 500 years ago, Admiral Cheng Ho brought the precious bird’s nest from Southeast Asia to the Chinese emperor. Since then, bird’s nest has been traditionally used by Chinese royalties and ancient beauties to maintain their beauty and body wellness.
During the golden period in the Tang Dynasty’s era, only the family of the Emperor and his court officials had the privilege to consume this supreme delicacy. It was after the imperial era ended, that the common people were introduced to swallow nests, where it was now widely termed as bird’s nest. Since then, due to its rarity and believed that the bird’s nests are rich in nutritional and historical values, demand and price for bird’s nest remain sky-high.
In order to understand more about this rare delicacy, there are a few basic things to understand. Firstly, the nest is taken from a bird called a swiftlet, swallow or salangane. Swiftlets, unlike most birds, and instead of twigs, feathers and straw, make their nests by expelling saliva (Chim yến in Vietnamese). The saliva dries and hardens upon contact with air to form the next which is edible. So, in other words, what you’re interested in is… bird spit. Once the nests are harvested, they are cleaned and sold to restaurants.
Swiftlets are birds contained within the four genera Aerodramus, Hydrochous, Schoutedenapus and Collocalia. The group contains around thirty species mostly confined to southern Asia, South Pacific islands, and north-eastern Australia, all within the tropical and subtropical regions.
Authentic edible birds’ nest (EBN) traded worldwide come from two heavily exploited species of swiftlet, mainly the white-nest swiftlet (Aerodramus fuciphagus) and the black-nest swiftlet (Aerodramus maximus). The nests were usually found attached to the ceiling of the cave or building (man-made house) in which the birds live.
The daily routine of swiftlets
On a daily basis, swiftlets leave their cave or the man-made birds’ nest houses as early as dawn breaks, around 6 am, foraging for food and for the excursion. Swiftlets are insectivorous birds that feed on aerial insects such as winged ants, fig maps and bees, flies, small beetles, etc. Ecologically, the swiftlets are important in controlling the population of insects. The swiftlets spend their entire excursion on the wing.
As dusk approaches, the swiftlets gather around the cave or house entrance, swirling and soaring, before entering. The swiftlets navigate in pitch dark caves or houses using echolocation. During the night, swiftlets settle in their nests in pairs. Swiftlets possess excellent instincts for locating their nest site and are able to locate and rebuild their nest on the same site, even if it has been removed.
Swiftlets breed throughout the year over three breeding periods. Breeding periods and nest quality are highly dependent on the species, location season and food availability. In general, a pair of swiftlets takes around 30 days from the start of the first salivary secretion to complete a nest and subsequently takes 7 days to lay the eggs. Generally, each pair produces one to two eggs per breeding period, depending on the species and the surrounding condition. The eggs are incubated for around 21 days before the nestlings are hatched. The nestlings grow up and eventually leave the nest in about 50 days after hatching.
Indonesia produces about 2,000 tonnes per year of the world’s bird’s nest, followed by Malaysia with 600 tonnes, and Thailand, 400 tonnes. The Philippines, around 5 tonnes per year, is the smallest producer. But Việt Nam is racing to catch up with Malaysia, Thailand, and the Philippines. Today the global edible birds’ nest industry is estimated to be worth USD 5 billion, most of it produced in Southeast Asia.
Birds’ Nest Colors
Swiftlet’s nests exist in three different colours: white, yellow (gold), or red (sometimes called “blood” nest). The colour of the edible birds’ nest (EBN) showed major differences following the place they are harvested, either from caves or houses. In caves, the two projections by which the nest’s cup is attached to the cave wall are usually stained with blood colour in fresh EBN but darken to brown with time, upon harvesting.
Some people believed that the EBN become red due to the saliva of the swiftlets building their nest were laced with blood, whereas some believed the swiftlets consumed lotus seeds, seaweeds or molluscs where the reddish hue mixes with the bird’s saliva. Studies were done on the red EBN, where it turns out that the red colour was due to the oxidation of nitrate in swiftlets’ droppings. The redness of EBN is strongly related to nitrate and nitrite, where the cave EBN has a higher content of the minerals, which gives the cave EBN, a slightly yellowish to reddish or darker coloured compared to the house EBN. The sodium nitrite within the EBN might cause the formation of aryl-C-N and NO2 side groups in aromatic amino acids of white EBN, which makes the white EBN transformed into red colour. House EBN usually appears whitish due to lower nitrate and nitrite contents.
Golden and Red types are rarer as they can be harvested only from certain caves in South East Asia and many connoisseurs believe that these types of nests have richer mineral content and higher quality, and therefore command a premium price.
So What’s so Special, Why so expensive?
For centuries, Chinese or born of Asian heritage have given their children the soup made by birds’ nest, believing it will help them grow healthier and quicker. Others consume it to improve their complexion and defeat lung problems, or as an all-purpose tonic. Some males strongly believed that the birds’ nest soup to be a sexual supplement and anti-cancer, whereas females think birds’ nest soup is good for their appearance (claims to help smooth the complexion and make them look younger) with its anti-ageing properties and perhaps most importantly, the high cost is a status symbol (and historically a sign of wealth and prestige) within the society.
The EBN goes under a glamour name “Caviar of the East,” sells for thousands of USD. In the nutshell, white and golden nests sold in retail are worth between USD 5,000-6,000 per kilogram. But the highest prized ones are reddish-brown nests, so-called “blood” nests, which can cost up to USD 10,000 per kilogram.
A bowl of birds’ nest soup in the restaurant can set you back around USD 100. Depending on the type of nest’s quality, origin and seasonal availability.
Unlike caviar and truffles, there are a lot of mysteries and mysticism around the birds’ nest soup. It’s claimed throughout centuries that they are attributed with remarkable nutritional ingredients, so they are said to be very healthy, even an aphrodisiac.
There is little peer-reviewed scientific data showing that nests have proven medicinal properties. Nutritional studies have shown the saliva to be approximately 62% protein, 27% carbohydrates, 8% moisture, followed by 2% minerals and 1% fat, similar to eggs. Furthermore, the gluey stuff (mucin glycoprotein) also contains small amounts of calcium, potassium, and phosphorus, but not in sufficient quantity to do any good, so claims about the birds’ nest soup treating and preventing illnesses are extremely strange and still a mystery to this day.
Having said that, the edible birds’ nest is still one of the most expensive food items in the world, which is probably a result of its extremely restricted availability, not its actual value.
Khánh Hòa Birds’ Nest
The coast, especially islands from the central province of Quảng Bình in central Việt Nam, to Phú Quốc island off the coast of Cambodia in the Gulf of Thailand are natural habitats for swiftlets.
But the three largest concentrations of EBN are in Chàm Islands in Quảng Nam in central, Phương Mai Peninsula in Bình Định is a province located in the South Central Coast and the swiftlet islands in Khánh Hòa Province.
Việt Nam has about 50 swiftlet islands with over 180 caves, of which 30 islands with 142 caves from Vạn Ninh District to Cam Ranh City, both within Khánh Hòa Province and are under the management of the Khánh Hòa Salangane Nest Company.
Khánh Hòa Province located in the South Central Coast has the largest number of islands which are home to the swiftlets and its products have been rated as having the finest quality in the region.
Of the 30 swiftlet islands in Khánh Hòa Province, the most famous swiftlet islands are Hòn Sam, Hòn Ngoại (largest natural swiftlets cave in Việt Nam) and Hòn Nội, but it’s Hòn Nội in Nha Trang City is the only island partially open for tourists five months a year. Too minimal human footprints and protect the sensitivity of breeding birds, their caves are strictly protected to prevent people from going near the islands. Moreover, to preserve the local environment and ensure sustainable development, the number of visitors is limited to 300 people per day near the islands.
How to harvest Edible Birds’ Nest?
The birds usually make their nests on the high vertical granite cliffs, so the workers must be skilled and brave mountain-climbers. To harvest their nests they have to erect bamboo scaffoldings on the steep cliffs. In some places where they cannot erect scaffoldings, they must use the rope to secure themselves to the mountainside, which is hundreds of metres high, in order to climb up or climb down.
The collection takes place three times a year (January, May, September) — after the birds rebuild their nests. Each of these nest takes around 30 to 35 days for the birds to build.
At this point, the men inside the cave take the ropes and tie them to handmade bamboo rattan ladders and scaffolding poles. These ladders will be hoisted up to the cave, at which point collectors will climb the ropes to assemble the scaffolding.
The collectors use the rattan hoops to lean back, which is an important safety feature in this process. The harvesting must be done before the birds lay their eggs to avoid damage — otherwise, the birds won’t lay them again for the remainder of the year.
However, collectors also have to be careful not to pick the nests too quickly, since if they’re not fully developed, they won’t meet the standards required to sell them. Since the female bird will go foraging for food during the day, this is when they come in to collect the nests.
The sun typically hits the cave during the day and allows for some light, though some parts of the cave will remain pitch dark all day. That’s why collectors often have to use flashlights when pulling the nests off the wall.
After the first nests are collected, the bird will build a second which is typically where the baby bird will live and grow, collectors wait three months — until it is ready to fly — before harvesting the nest.
Constructed with feathers that are conjoined with the bird’s saliva, the black nests need cleaning before they can be sold. Traditionally they are picked out with a small instrument, though commercial cleaners often use a bleaching agent to speed up the process.
After the nests are collected and cleaned, they are exported mainly to China, Hong Kong and Taiwan, but the domestic market is strong for local farmed EBN. China is the world’s largest consumer of birds’ nests, accounting for more than 90 per cent of consumption. Cave birds’ nests are usually higher priced than farms.
Birds’ Nest Farming
With its long coast and mangrove and protective forests that are extremely rich natural habitats for many types of insects, Việt Nam has huge potential for breeding swifts.
With Asia’s, increasingly wealthy population demands more EBN and Việt Nam is keen to become a major producer of the delicacy.
The Ministry of Agriculture and Rural Development promotes and encourages southern birds’ nest companies to discuss measures to further develop bird nest farming in the area.
Farms generally produce much cleaner bird’s nests due to the controlled environments where the nests are built, resulting in a high-quality harvest. Licensed farms also practice sustainable harvesting where the nests are only collected after they are abandoned by the swiftlets. Cave nests, on the other hand, are built on the walls of caves and contain more foreign materials and impurities as compared to house nests.
Bottom line: the lower the saliva % and the more processing and cleaning required will result in a low-quality bird’s nest. Nest with 95% saliva concentration would be the best while a concentration of 50% and 10% saliva would fall into the second or third tier.
The birds’ nest farming and trading started in 2004 from southern provinces. As of now, 9,000 households in 42 out of 63 cities and provinces in Việt Nam are breeding swift for bird’s nests and the numbers continue to grow. The Mekong Delta has the most number of bird’s nest farmers, followed by the Southeast Region and the Central Coast.
10 years ago the whole country had about 1,500 swiftlet farming houses with an output of one tonne of nests a year of which Khánh Hòa Province produces half. It is expected that by the end of 2020, the number of these houses will increase to about 10,000, making a great contribution to preserving this species of bird and increasing the national output.
To increase the success in birds’ nest farming, the design it to resemble a cave. The sound used in the building is recorded from the cave or any other successful birdhouses. Correct temperature, wind, humidity, smell and lighting are vital.
The lucrative industry is not without high risk. After an initial investment of USD 80,000 to US$500,000 to build a birdhouse structure, and the monthly cost of about USD 50, a successful operation can earn as much as USD 1 million annually. However, there is no guarantee investing in a birdhouse will pay off. Many structures fail to attract birds, and if disease hits a birdhouse, the entire investment could be lost.
Authenticity & Quality Standards
Unfortunately, due to the increasing popularity of edible bird’s nests, many have resorted to unscrupulous means of either adulterating Bird’s Nest products to make them appear as though the content is higher than the actual; using nitration or bleaching methods to alter the colour of the bird’s nest to increase its perceived premium value, or using adulterants or ingredient substitutes to create fake bird’s nest (maybe harmful).
The research has shown, common adulterants, nitration and bleaching methods have been identified.
Factors like deforestation, pollution, and uncontrolled harvesting have threatened the population of swiftlets. In a study conducted between 1997 and 2009 that observed the swiftlets, it was noted that owls, raptors, snakes, geckoes, bats, cats, rat cockroaches, lice, flies, giant crickets, and centipedes are all predators to this tiny bird. However, the biggest threat to swiftlet’s existence is humans.
Lack of regulations and specific reforms from the Government Animal Husbandry Development Strategy. As a result, safety and disease managements are not guaranteed. In addition, many businesses have not invested enough in processing facility and technology, therefore, the products are typically exported raw with low value.
All collectors insist they do not harvest any nests until the eggs have hatched and chicks have left the nests has thrown the claim into doubt. It is at this time that the nests are most translucent and least contaminated by bird droppings and feathers, thus selling for as much as USD 5,000 per kilogram! Many companies argue, logically, that it is in their best interest to preserve and protect the birds, thus ensuring future sales. However, it’s no surprise that in a region where income is minimal, the nests represent temptation for poachers who have no regard for the survival of the species, only their own survival. The first nests often are gathered even before eggs are laid – which actually is permitted as the adult birds often then build another – but late, eggs and baby birds often are thrown away, which is illegal. The poachers, some of them former employees who know the cave locations, bribe the armed guards hired by companies to safeguard their contracted rights by making them partners in the late-night theft.
The Convention on International Trade in Endangered Species (CITES) has asked all countries in the region to conduct more scientific research in order to promote the sustainability of the harvesting through best-practice programme managements.
Recommendations for improved management of the nest harvest include addressing corruption, ensuring that local people with traditional rights to collect nests do not lose income to illegal immigrant labour and to traders, improving research and education about the swiftlets behaviour and ecology, and moving value-added processing of the nests closer to the caves where they originate and to the people who collect them.
Lastly, authorities should make clear zoning plans and regulations related to quality standards, farming and processing. Experts blamed this on the development of hospitality projects and even industrial parks along the coast, which reduce the populations of insects on which the birds feed. Therefore, swiftlets must fly deep into the mainland to find food, and 50-60 per cent of young birds do not return to islands.