After autumn comes, larvae which have not yet matured lose some of their vitality, and pass the winter in a state of semi-hibernation. If they have passed into the pupation stage, they find some soft mud or burrow into a stream bank or dike, passing the winter in the cocoon.
時序入秋後，尚未長大的幼蟲，活動力減低，以半休眠狀態度過冬天，若進入化蛹期，則選擇鬆軟的泥土，或爬至溪流邊坡、土堤裡鑽洞，利用蛹期度過冬季。