Introduction: The common kingfisher is a small bird of the kingfisher family, with a body length of 16-17cm, a wingspan of 24-26cm and a body weight of 40-45g. However, the body is smaller, the body color is lighter, the ear cover is brown, the wings and tail are blue, the lower body is reddish brown, and there is a white spot behind the ear. The female bird's upper body color is slightly lighter than the male bird, more blue, less green. The top of the head is not greenish black and is grayish blue. The chest and abdomen are brownish red, but the males are lighter and the chest is gray. The color of the young bird is lighter, the upper body is less blue, the lower body is lighter, the color is more brown, and the center of the abdomen is white. Alone or in pairs. Sexual loneliness, usually on the branches or rocks near the water, waiting for the opportunity to hunt food, food is mainly small fish, eat crustaceans and a variety of aquatic insects and their larvae, also eat small frogs and a small amount Aquatic plants. When the kingfisher is plunged into the water, it maintains excellent vision, because its eyes can quickly adjust the contrast of the light caused by the light when it enters the water. Distributed in North Africa, Eurasia, Japan, India, Malay Peninsula, New Guinea and Solomon Islands.