A wild bird of the crow family with a characteristic light blue from the back to the tail feathers. The head is black, and the area from the neck to the back is gray and looks a little dirty. As the name suggests, it has a long tail. They are acting in a flock, screaming in a loud voice, "Guy Guy". Looking for food while going back and forth between the ground and the trees. The appearance of moving while fluttering on the ground and moving while squeaking is similar to a crow.
As a resident bird, it inhabits in groups in urban areas and trees near forests. While orbiting their living area, they search for and eat food such as insects and nuts. While being alert to the surroundings, when there is danger, they communicate with each other by crying and jump up to the high treetops. The characteristic loud cry is the voice when you are alert, and when you are not feeling the danger, you may say "chupichupi". Act in groups and breed together. Young males in the herd act as helpers to help other individuals raise their children.
They flew around Sarue Park, Koto-ku, Tokyo. It was wary of people, mixed with starlings and thrushes, and went down to the ground looking for food. When the number of people was increasing around noon, the group moved to another place while screaming loudly. I was able to observe them well because they were perching on trees with good visibility such as cherry blossoms and pine trees and looking around.