Two garden eels at the Kyoto Aquarium were filmed engaging in a territorial dispute involving aggressive staring and physical strikes [1].
The footage provides a rare glimpse into the social dynamics of garden eels, which are typically viewed as passive. Understanding these behaviors helps researchers and the public recognize the biological drivers of aggression in captive marine life.
In the video, the two eels [1] are seen staring at one another and opening their mouths as a form of intimidation. The encounter culminates in one eel delivering a quick forward "punch" to its opponent [2].
Tomoya Serigano, a member of the exhibition-captive team at the Kyoto Aquarium, said the animals were clearly fighting. He said that the eels open their mouths wide and stare each other down during these disputes [2].
According to Serigano, the aggression stems from the fact that garden eels maintain individual micro-territories [2]. He said that the eels may fight when they attempt to assert their ownership of these specific spaces [2].
Other aquarium staff said that territorial disputes are a known behavior among the species [3]. While some observers may view the interaction as humorous, the behavior is a functional part of how the animals manage their environment [2].
Garden eels typically live in sandy bottoms where they burrow themselves, leaving only their upper bodies exposed to feed on plankton. Because they cannot move their burrows, the space immediately surrounding their hole becomes a critical asset to defend [2, 3].
“The eels open their mouths wide and stare each other down during these disputes.”
This observation highlights the inherent territoriality of garden eels, a species often perceived as docile due to their sedentary nature. By documenting the specific sequence of aggression—from visual threats to physical strikes—the Kyoto Aquarium provides data on how these animals resolve spatial conflicts in a captive environment where territory is limited.
