An Osaka Metropolitan University Graduate School of Science team led by Ph.D. student Yuya Kobayashi and Professor Satoshi Awata found evidence of this feeding behavior during field experiments. They saw Clark’s anemonefish actively provisioning food to bubble-tip anemones, such as by attaching a clam they cannot eat to the tentacles of their hosts. For smaller food, the fish had their fill first before feeding on the sea anemones.

“We also confirmed that feeding the anemonefish directly increases the growth rate of the sea anemones,” stated Ph.D. student Kobayashi. “It is known that in other anemonefish species, the number of eggs laid increases when the hosts are larger. For anemonefish, which cannot leave their sea anemone, feeding their hosts is extremely important and will ultimately benefit themselves.”

Professor Awata added, “We believe that correctly understanding animal behavior will not only lead to the development of ecology, biology, and other fields of research, but will also provide appropriate methods for the protection and conservation of animals that are on the verge of extinction.”