The nest used in bird's nest soup is composed entirely of saliva.
The soup is made by soaking and steaming the nests in water.
It is said to improve kidney health, reduce phlegm, and to be an aphrodisiac.
The nests can fetch high prices and many colonies are harvested commercially.

Some populations such as those in the Andaman and Nicobar Islands have been harvested extensively leading to them being considered critically threatened under the IUCN criteria.

The use of artificial bird houses is growing.
A detailed account of modern nest farming and marketing techniques is given by David Jordan (2004).
In Indonesia and Malaysia , "farming" of nests is performed in purpose-built structures or old empty houses with "tweeters" playing recordings of bird calls on the roof to attract swiftlets.
In urban areas, such "bird houses" may be considered a nuisance by neighbours due to the loud bird calls and bird feces.
The nest used in bird's nest soup is composed entirely of saliva. The soup is made by soaking and steaming the nests in water. It is said to improve kidney health, reduce phlegm, and to be an aphrodisiac. The nests can fetch high prices and many colonies are harvested commercially.
Some populations such as those in the Andaman and Nicobar Islands have been harvested extensively leading to them being considered critically threatened under the IUCN criteria.
The use of artificial bird houses is growing. A detailed account of modern nest farming and marketing techniques is given by David Jordan (2004). In Indonesia and Malaysia , "farming" of nests is performed in purpose-built structures or old empty houses with "tweeters" playing recordings of bird calls on the roof to attract swiftlets. In urban areas, such "bird houses" may be considered a nuisance by neighbours due to the loud bird calls and bird feces.
Edible-nest swiftlet