About Swiftlet

Unique Bird

Southeast Asia’s swiftlet of the Aerodramus Fuciphagus species is one of the most unique birds in the world. They have long, crescent shaped wings with very short bills, a wide mouth and very small, weak feet. They measure about 12cm in its entire length and weighs slightly less than 20 gm. They have brownish gray feathers across its rump with a very strong ability of flight; in fact they are the fastest fliers known, averaging at 140 km/h with a top speed of up to 170km/h and capable of a 40-hour non-stop flight. Because of their weak feet, they are unable to stand on the ground or tree branches; their sharp claws enable them to only perch by hanging upright when they are sleeping, building their nests or feeding their young. Their habitat includes rock shelters, caves and other cave-like conditions including buildings, culverts and tunnels. Swiftlets feeds on insects caught in flight. The monogamous parents lay 2 eggs (sometimes one) incubated by both parents for about 14 days. The chicks will remain inside the nest for about 45 days, before they are fully independent from their parents.  The average life span of the swiftlet is estimated at 12 years (but varies from 8 to 15 years).

But the most interesting feature about these swiftlets is their nest. They will construct their nest with glutinous strands of starched like saliva produced by a pair of large, salivary glands under their tongue and thereafter mate and breed their young. It is this starched like strands that constitutes the raw material of birds' nest soup and renders the nest its commercial importance. The nest looks like a cupped hand or a half cut bowl about 3-5” in diameter. The flat side is stuck to a wall (a cave wall in wild nests, or a wooden base in cultivated or house nests) and the other side of the nest is a place for them to perch and within the hollow of the nest are either their eggs or their chicks.

Bird's nest soup with rock sugar

A surge in demand for the consumption of bird’s nest soup, which for the Chinese has been a form of traditional cures for all kinds of ailments namely those involving the respiratory system has caused its price to spiral upwards. Its demand has exceeded its supply by such a margin that a kilo of raw unprocessed nest has risen from a mere US$20.00 per kilo in the seventies, to about US$2,000.00 per kilo today (Dec. 2001). The Chinese uses these edible bird’s nest for cooking up all kinds of exquisite cuisine, initially fit only for the Imperial household (as early as Tang Dynasty A.D. 618-907). 

Swiftlet Species

There are about a hundred different species of swifts and swiftlets all over the world and the kind of species found in this part of the world (Southeast Asia) consists of about 50 different species. Out of these 50 odd species only about 5 species are commonly seen in these areas. They are of the order of Apodiformes and from the family of Apodidae known scientifically as Aerodramus Fuciphagus (white nest swiftlet), Aerodramus Maxima (black nest swiftlet) Aerodramus Esculenta (grass nest swiftlet), Aerodramus Vanikorensis (mossy-nest swiftlet), and Aerodramus Brevirostris. 

Recognizing the right type of swiftlets and their habitat plays a vital role and one of the most important factors of cultivating the edible nest swiftlet. Knowing the swiftlets daily routine and their activities, the bird’s nest operator or building owner will find maintaining the bird’s nest farm easily manageable.

About 100 species of swiftlet around the world

We will study here, only the 3 main edible nest producing swiftlet; namely C. Fuciphagus (also known as Aerodramus Fuciphagus), C. Maxima (Aerodramus Maximus) and C. Esculenta.

Aerodramus Fuciphagus Species 

This specie is popularly known as the White Nest, House Nest or Wild/Cave Nest swiftlet. They construct their nests with a glutinous nest-cement produced by a pair of large, lobed salivary glands under the tongue. It is this nest-cement that constitutes the raw material of birds' nest soup and renders the nest its commercial importance. The glutinous strands content in the nest of this specie is about 85-97 % in its unprocessed form, making it the most sought after in the market as well as commanding the highest price. The nest is most popularly sold in its entire piece whereas broken pieces are made into strips, crumbs or moulded into cakes.  Most if not all bird’s nest farms cultivate this particular specie.
 

A. Fuciphagus measures about 12 cm in its entire length and weighs about 15 to 18 gm. This swiftlet has a band of brownish gray feathers across the rump with dark brown eyes, black beak and feet.  Eggs are laid 2 at a time, slightly oval in shape and white in colour. This specie can be found in most South East Asian countries especially the islands of Indonesia, Malaysia, Philippines and Thailand.

Collocalia Maxima Species 

This species’ popular name is Black Nest, because it uses its blackish brown feather together with its glutinous strands as ‘cement’ for making its nest, thereby making its nest blackish in colour. Its feet have feathers all over and thus contribute in the formation of its nest.  The glutinous strands content in this nest is only 5-15% in its unprocessed form. This nest is very popular in making bottled or canned bird’s nest, and sold most popularly in cake form or as strips and crumbs.

C. Maxima is larger than the Fuciphagus measuring averagely at 13 cm and weighs about 28 gm. At a glance this 2 specie might look the same but on closer examination they are quite different. The distinguishing difference is its lower leg grows a row of small feathers. This swiftlets nests can be the red-legged or white-legged form and usually lays one egg.

Aerodramus Esculenta Species 

Its popular name is Grass Nest as it uses grass with its glutinous strands as cement for making its nest. The nest is normally brownish in colour with the glutinous strands content at about 5-15% in its unprocessed form. This swiftlet nest is highly demanded for restaurant consumption and is sold most popularly as strips or in crumbs and cake form. This specie has a glossy, darkish blue-black colour and is the smallest of the 3 species measuring only about 10 cm. in length.

All the above 3 species has slightly parted tails.  Good quality nests from these species can be distinguished by the firm, white basal attachments and a comparatively large proportion of nest-cement with few feathers/grass in the nest-cup, a thick body and in perfect shape, form as well as colour.