Distribution: Bird's nest in Jin Siyan, mainly distributed in India, Southeast Asia and Malay Archipelago, lives in groups. Fangwei Jin Siyan, produced in Sarawak, Malaysia, has more than 2 million animals in a big cave on the coast of Virginia, which can be regarded as the largest settlement in Jin Siyan. Jin Siyan with short mouth is produced in the west, southwest and even southeast of Xizang Autonomous Region in China, but edible bird's nest is not produced. Edible bird's nest can be produced in Jin Siyan, Java and Hainan Island, but the number is limited, and the largest population is only 60~70 now.
The average body thickness (including hair) of an adult Jin Siyan is about 4 cm, the body length is about 65438 00 cm, the wings are about 22 cm, and the weight is about 20 grams. His feet are short and soft, and his four toes are facing forward, so he can't catch them. Therefore, unlike ordinary birds, they can perch on wires or walk forward on the ground with three toes. Jin Siyan can only hook on a vertical wall or rock wall with four toes. Jin Siyan has a good sense of echo location, and can fly freely in the dark environment to find its original habitat. Adult Jin Siyan lays eggs three times a year, and April, August and June are the peak months for Jin Siyan to lay eggs. Two white eggs are laid at a time, about 2.0cm long, 1.2cm wide and about 3.5g g in weight. The nesting begins about 30 days before laying eggs, and it takes about 30 days for male and female swallows to build a nest together. The incubation period of eggs is about 20 days.