The gopu, known as sailfish, is one of the fastest fish in the ocean, reportedly reaching up to 55 km/h, although its speed is not just due to swimming prowess.   

Gopu are also known for the large 'sail' fin, that extends from the nape of its back to the adipose fin. When hunting, the sail is extended, to counterbalance a swift lunge at its prey and ensuring the sailfish aims accurately with it’s sharp, pointed bill. These bills are also used to shepherd schools of fish into target positions, ‘tapping’ or ‘slashing’ horizontally.

A gopu grows more than a meter in length each year, on its steady diet of squid and small pelagic fish.