The climbing perch is a low-oxygen-tolerant freshwater fish that can walk on land

The climbing perch is a freshwater fish of the genus Anabas in the family Anabantidae, commonly known as the climbing perch or tree-climbing fish. It is widely distributed in still or slow-flowing waters of South Asia and Southeast Asia, and can also be seen in ponds, rice paddies and ditches in some southern provinces of China. Its body is laterally compressed, and its body color is mostly brown or grayish green, with serrated hard spines along the edge of the gill cover, making its appearance somewhat similar to that of the crucian carp.

The most famous feature of the climbing perch is its labyrinth organ, an accessory breathing organ that allows it to swallow air directly to breathe, so it can survive even in low-oxygen shallow water. It can also use the hard spines of its gill covers and the support of its fins to crawl short distances across moist land, moving from one body of water to another. As for the claim that it climbs trees, this comes mostly from early rumors; its actual mode of movement on land is crawling rather than climbing.

This fish has a strong ability to adapt to its environment, tolerating low oxygen and muddy conditions, and it often appears in swamps, puddles, rice paddies and other waters prone to drying up. Its diet is omnivorous, including small fish, shrimp, aquatic insects and plant debris, and it forages actively and has low requirements for water quality.

In its native range, the climbing perch is a fairly common food fish. Because it tolerates low oxygen and survives for a relatively long time after leaving water, it is relatively easy to transport and hold temporarily, giving it some aquaculture value. However, its dispersal and adaptability are strong, and once it enters natural waters outside its native range, it may compete with local fish for living space, so releasing it at will requires caution.

If it is kept as an ornamental fish, the tank should be covered to prevent it from climbing out, while water quality should be kept stable and hiding places provided. Overall, thanks to its special ability to survive out of water, the climbing perch has become a rather noteworthy group among freshwater fish, and learning about it also helps in understanding the diversity of fish breathing and adaptation methods.