GOMANTONG CAVE - Home of Swiftlet Nests, Which Are Harvested For Bird's Nest Soup (Borneo)

The Gomantong Caves are an intricate cave system inside Gomantong Hill in Sandakan Division, Sabah, Malaysia. Situated in a Sabah Forestry Department forest reserve, the caves and the surrounding area are a protected area for wildlife, especially orangutans.
The main cave system is divided into two parts: the more accessible Simud Hitam (Black Cave), and the larger Simud Putih (White Cave) which lies above. The names refer to the main type of nests produced by swiftlets in each cave. The cave system is home to many other animals, including massive populations of cockroaches and bats. Outside one can see many raptors including crested serpent eagles, kingfishers, and Asian fairy-bluebirds. Access is in the form of a wooden walkway circuiting the interior.
For centuries, the caves have been renowned for their valuable edible swiftlet nests, which are harvested for bird's nest soup. The most valuable of the nests, the white ones, can sell for very high prices.
The birds' nest collection is an ancient tradition, and the trading of these nests has been done since at least 500 AD. Twice a year, from February to April and July to September, locals with licenses climb to the roof of the caves, using only rattan ladders, ropes, and bamboo poles, and collect the nests. The first collection takes place early in the breeding season before the swiftlets lay their eggs. The birds then make another nest in which they finally lay their eggs. After the young have fledged, the second collection is made. These individuals are very much in demand by the people and communities that hold the Government's harvesting licenses.