Abstract:Based on the CINRAD/SA and dualpolarization weather radar data of Yingkou in Liaoning Province during 2018-2020, the early morning departure activities of birds from their habitats in the Liaohe River Delta Wetland and the surrounding areas are analyzed. The results show that there are obvious seasonal and daily changes in the activities of birds in the Liaohe River Delta and the nearby wetland.The echo of birds detected by weather radar is concentrated from late July to mid October, especially from August to September. There is a positive correlation between the time of bird echo and the time of daybreak. The echo of birds shows obvious ring-shape characteristics on the reflectivity products, and the strongest can reach more than 40 dBz. In terms of Doppler velocity products, they are divergent. In the case of high wind speed, the echo of the birds deviates significantly to the downwind direction. The distribution of difference reflection (ZDR) of the bird echo is not uniform, and the maximum reflectivity is 3-7 dB. The correlation coefficient (CC) of the bird echo is small and uniform, which is different from the ground echo, and is related to the intensity of the reflection factor of the echo. When the reflection intensity is greater than 30 dBz, CC is between 0.7-0.8. When the reflection intensity is less than 30 dBz, CC is mostly less than 0.6. Dual polarization radar products have obvious advantages in the recognition of bird echo, which can effectively eliminate the bird echo in precipitation and improve the accuracy of short-term and nowcasting forecast. However, the differential phase shift rate (KDP) and HCL do not reflect the echo of birds.