Six critically endangered hog deer have been set free in Cat Tien National Park, marking the first step of a plan to return 30 animals to the wild. Understanding each step of this careful process shows how scientists give a second chance to a species on the brink.

The first phase involved four females and two males. Saigon Zoo and Botanical Gardens carried out the release in coordination with the park, and the operation was performed during the night to limit disturbance from light, noise and human activity.

Veterinarians gave each deer a health assessment, then sedated them and provided supportive medication to reduce stress during the 150‑kilometre journey. After sedation the animals were placed in specialised crates lined with straw, and cold water bottles were added to help keep their body temperature stable.

Before they left the crates, every deer was implanted with an electronic identification microchip so that conservationists can monitor movements and survival after release. The night‑time timing was chosen specifically to minimise stress caused by human activity.

Future releases will be decided based on how well this first group adapts and survives in its new forest home. If the six deer thrive, more will follow until the target of 30 individuals is reached.