Study conducted at Nagasaki University reveals Bathynomus doederleini, deep‐sea isopods, consume large quantity of food: One meal could provide six years' worth of energy

Bathynomus doederleini can consume up to 45% of their body weight at a time, and their metabolic rate increases after eating. A study by Associate Professor Mitsuharu Yagi of the Faculty of Fisheries, Nagasaki University, postgraduate students Shogo Tanaka, Yurika Ono and Shin‐ichiro Tanimae of the Graduate School of Fisheries and Environmental Sciences, Nagasaki University, Associate Professor Toru Moriyama of Shinshu University and Dr. Shingo Fujimoto of University of the Ryukyus revealed these results. The study was published online in Deep Sea Research Part I: Oceanographic Research Papers.

This phenomenon is a specific dynamic action and has been reported for the first time in deep‐sea organisms. It was also revealed that a 10 ℃ increase in water temperature led to a 2.4‐fold increase in metabolic rate. This species is estimated to acquire enough energy to survive for approximately six years after a single meal if compared in terms of whale blubber.

Yagi said, "This research was conducted in response to a report that the giant isopod Bathynomus giganteus, a species closely related to deep‐sea isopod Bathynomus doederleini, had survived without food for five years in an aquarium. This raised the questions, 'How do they survive for such a long time without consuming food?' and 'How much energy do they require to survive?' Once one question is clarified, further questions continue to arise. Currently, we are researching Bathynomus doederleini using large training ships, such as the Nagasaki‐Maru and the Kakuyou‐maru, from the Faculty of Fisheries, Nagasaki University. We look forward to uncovering further information on this topic."

Journal Information
Publication: Deep Sea Research Part I: Oceanographic Research Papers
Title: Metabolic responses to food and temperature in deep‐sea isopods, Bathynomus doederleini
DOI: 10.1016/j.dsr.2023.104019