Brandt's reed warbler is a small bird. The male and female have similar plumage. It may be a summer migratory bird in Xinjiang, China, and a stray bird in Hong Kong. It often moves alone or in pairs. It is lively and alert. It often jumps on low trees or flies between small trees. It is busy looking for food all day long, and it often fan its tail feathers and swings them. During the breeding season, male birds mostly sing at night. During the peak breeding season, they sing continuously during the day and night. Their singing is sharp, fast, urgent, and varied, and their sound is like a repeated "chip-chip-chip..." sound.
They mainly feed on insects and larvae of Coleoptera, Lepidoptera, Orthoptera, such as caterpillars and grasshoppers, and also eat other invertebrate foods such as locusts, beetles, spiders, etc.
The breeding season is from May to July. The nest is built near the water, on dense bushes and grass a few centimeters to 1 meter above the ground. The nest is cup-shaped, made of grass leaves and stems, with thinner grass stems and sometimes animal hair inside. The size of the nest is: 9-13 cm in outer diameter, 5-6 cm in inner diameter, and 3-4 cm deep. It usually takes 3 days to build a nest. Each nest lays 3-4 eggs. The color of the eggs varies greatly and can be divided into 3 types: ① light pink, with light reddish brown spots and gray-purple patches; ② milky white, with olive brown spots and gray-purple patches; ③ dirty white, with super-large cinnamon brown spots. The size of the egg is 17-19 mm × 12.8-15 mm.
Listed in the IUCN Red List of Threatened Species in 2017 ver 3.1 - Least Concern (LC).
