Acknowledgments
The research was logistically supported by the Uryu Research Forest, Hokkaido University for fieldwork. We acknowledge staff members at Uryu Research Forest, Hokkaido University, including Tetsuro Nakaji, Rei Sakai, Yuko Hara, and Tohru Miyazaki. We thank many student volunteers who assisted fieldworks. This study was financially supported by KAKENHI Grant Number 21H04784 to H.U. from the Japan Society for the Promotion of Science. Our work conforms to the guidelines for the proper conduct of animal experiments in Japan. Field survey of aquatic animals was approved by the fishery and forestry department of Hokkaido (ID 610).