The breeding period of the Yellow-browed Warbler is from May to August. Pairing begins 15-20 days after moving into the breeding ground. Usually the male bird stands on the treetops and looks around. When he spots a female bird, he quickly flies to her, lowers his head and wags his tail to show off his courtship. Female birds tend to avoid and fly away quickly. Later, it is common for male birds to sit high on the treetops and emit gaji..." continuous mating calls. At this time, the female bird sometimes jumps on the branches, sometimes flies into the air, until the female bird does not escape from the male bird, and the male and female birds move together and are inseparable. , and eventually become mates. After pairing, both male and female birds choose the same nest site. They nest on the gentle branches of the forest, on the sunny grassy slopes in the open areas of the forest. They can also be found in areas such as the dead branches and leaves on both sides of the road, and have been found near houses. On a pine tree, a nest was found at the bifurcation of the main trunk and side branches. It was 3-5m high from the ground. The nest was very hidden.
After the nest site was determined, the female bird built the nest with wood in her mouth. There were many male birds. It is the companion of the female bird in transporting materials. The female bird carries materials continuously throughout the day, and the number of times it can be carried up to 145 times a day is that the nest is spherical, has a fine structure, and is not easily loose and deformed. The nest is made of moss, sandgrass, bluegrass and some other materials. It is composed of fibrous dead bark, etc., and is lined with plant fibrous roots, animal hair, bird feathers, etc. The nest (30 pieces) is 14.5 (12.5-16.7) cm long; the nest width is 12.5 (11.7-13.4) cm; the nest height is 9.5 ( 8.9-12.7) cm; nest depth 8.7 (7.3-9.2) cm. The entrance and exit of the nest is located in the front, with a diameter of 3.8 (3.3-4.2) × 3.5 (3.3-3.8) cm. It takes 7-9 days to build the nest. 10-12 days.
Egg-laying begins after the nest is built, usually between 5 and 9 am. One egg is usually laid every day. Occasionally, mating occurs every other day during the egg-laying period. The parent bird picks up wood and repairs it. At this time, the female bird does not incubate the eggs and does not spend the night in the nest. The eggs are usually oval or spherical, pink or white, with blunt ends. Decorated with dark brown spots. The average weight of the eggs (107) is 0.9 (0.7-1.1) g, and the average size is 11.9 (10.0-13.0) mm × 10.0 (8.9-11.5) mm.
Incubation period. 10-12 days, sometimes up to 13 days. The female bird is responsible for incubating the eggs. The egg shell is taken out of the nest by the parent bird, and the unfertilized eggs remain in the nest until the parent bird leaves the nest.
Brooding period 8. -10 days. The female bird is responsible for brooding. During the brooding period, the broodbirds feed at various locations, but they mainly feed in the middle of the tree canopy, in the upper layers and on the bushes. Sometimes they are seen flying into the air to hunt for food, but none were seen. Foraging on the ground.
During the brooding period, it is common for the parent birds to pick up the feces of the chicks from the nest to keep the nest clean. The chicks remain in the nest for 8-10 days. Unable to stand on its own, it moves away from the nest and never returns to the nest. It often hides in bushes or grass and waits for feeding by its parent birds. After the parent birds brood outside the nest for 8-10 days, the young will peck for food on their own and become independent. Life, but the young bird's flying ability, ability to avoid enemies, diversity of feeding, and flexibility still need to be exercised and gradually mature.