METHODS
The investigation site is located in a Spartina swamp (E120°29′50.00″; N33°48′35.17″) near the south of Sheyang Port in Yancheng City, Jiangsu Province. The area is bout 3.78km2, the perimeter is about 11km (See Fig.1.). The first discovery of Reed Parrotbill entering Smooth Cordgrass was at noon in November 2021. We accidentally heard the chirping of the Reed Parrotbill.