Sydney Aquarium has released 30 captive-bred seahorses into Sydney Harbour as part of a research programme to boost their numbers.
The creatures will be closely monitored so see how captive-bred seahorses manage in the wild.
The programme was funded by the Sydney Aquarium Conservation Fund and developed by NSW Department of Primary Industries marine scientist David Harasti.
Aquarium chief executive Kevin Bush said: “Sydney Aquarium is more than a major tourist attraction – we also aim to protect and restore endangered aquatic species and build awareness of marine issues through the work of the Sydney Aquarium Conservation Fund.”