The Formation Process of Bird's Nest Bird's nest is a structure built by a species of swiftlet called the "golden-threaded swiftlet." These birds inhabit the waters around Southeast Asia, Indonesia, Singapore, and Thailand, preferring to nest in groups within caves on the sheer cliffs of Hainan Island. They construct their nests using moss, seaweed, and soft plant fibers mixed with their feathers and saliva, binding the materials together to create a shelter.Humans harvest these nests, which undergo refinement and sorting to become the prized bird's nest. Below is an introduction to the formation process:
Method/Steps 1. Bird's nest, as the name suggests, is the nest of a swallow. However, it is not the nest of an ordinary swallow, but rather that of a special species—the swiftlet.The swiftlet belongs to the order Apodiformes, family Apodidae. As migratory birds, they fly from Siberia and other regions to natural caves along tropical coastlines between December and March each year to breed.
Swiftlets are smaller than the swallows commonly seen. Their back feathers are grayish-brown with a golden sheen, their wings are long and pointed, and all four toes point forward.This species possesses highly developed mucous glands in its throat, secreting saliva that solidifies in the air—the primary material for their nests. Swiftlets lay eggs in March or April each year. Before breeding, they fly daily over the sea surface and at high altitudes, sometimes reaching thousands of meters, piercing clouds and mist to absorb rain and dew while feeding on insects, seaweed, and silverfish.After digestion, they retreat to the crevices of steep, shaded cliffs at higher altitudes or deep within caves to regurgitate saliva and construct their nests. This process takes approximately 20 days to complete.
The nest is crescent-shaped, resembling a human ear, with a diameter of 6 to 7 centimeters. It features a thick base and thin walls, weighing about 10 to 15 grams.The exterior is smooth while the interior is rough, resembling a loofah net. The entire nest is pure white, translucent, and elastic, adhering to rocky cliffs. 2. Nests built by mature swiftlets are formed entirely from thick mucus secreted from their throats, gradually solidifying into a pure substance. This type of nest is considered the highest quality and finest grade among bird's nests.During the feudal imperial era, these nests were frequently selected as tribute offerings, hence the name "official bird's nest" or "white bird's nest."
3. Nests built by young swiftlets are rougher due to their inexperience, containing more impurities and feathers. The harvested raw material from these nests is called "raw bird's nest."
4. Another variety absorbs red liquid seeping from adjacent rock walls, turning the nest's wall-adjacent sections crimson. Known as "blood nests" or "red nests," these contain minerals, offer superior nutrition, and are extremely rare—regarded as the rarest treasure among bird's nests.
Bird's nests are not ordinary swallow nests but those of a specific species—the swiftlet. Swiftlets belong to the order Apodiformes, family Apodidae. As migratory birds, they fly from Siberia and other regions to natural coastal caves in tropical areas between December and March each year to breed.
Formation of Blood Nests
1.In reality, all blood nests originate from nests built by swiftlets on cave walls. Typically shaped like a half-cupped hand holding water, their form can vary based on the environment they adhere to. Most take the shape of a quarter sphere or a triangle.
2. Swiftlets feed on coastal algae, insects, and flying ants from deep mountain areas. Consequently, their saliva contains higher mineral content, causing the nests to oxidize and turn red.
3. Minerals from the ancient rock walls gradually permeate the nests through contact surfaces. Combined with mineral-rich cave water dripping into the nests, this process causes color transformations.
4. The cave air is extremely humid and hot, intensifying deeper inside. The mineral-rich nests oxidize under this heat, turning grayish-red or clear red.
How to Distinguish Authentic Blood Swallow Nests
1. Many who have consumed blood swallow nests may notice a pale yellow liquid released during soaking. Rest assured, this is entirely normal. Since blood swallow nests remain semi-wild even in modern swallow houses, they contain more impurities than white nests. Blood nests are generally larger, thicker, and harder in texture.
The key to selecting blood nests lies in choosing those with uniform coloration and minimal blackened areas. These darkened sections tend to release sand-like impurities during the soaking process. Thus, the pale yellow water color is caused by dissolved impurities, not dye leaching.
2. If the soaking water turns red, this is a clear sign of dyed bird's nest.
3. Authentic blood nests have a firm texture. Even broken pieces won't dissolve into water after stewing for three to four hours. Dyed nests, however, either soaked in chemicals or counterfeit nests made from pig skin, will dissolve completely after just an hour and a half of stewing.
4. No pungent odor is present during soaking or stewing.