The Asian Arowana faces two main threats, namely overharvesting for the aquarium trade and destruction of its natural habitats.
Due to high demand and value in the aquarium trade, the Asian Arowana is highly harvested in the wild and in farms. Black market exploitation is also a problem since it goes unchecked, and illegal trade of this fish continues around the world.
In the wild, some harvesters use methods that involve the killing of the mouthbrooding male adult (e.g. spears, knives, electrofishing) in order to spur the release of the Arowana fry. Other methods involve frightening the male into releasing the offspring. The fry are then captured, since they survive the ordeal better and are easier to transport, and sold for a hefty profit.
In Cambodia, a study has shown that the effects of such methods of harvesting have been dramatically affecting the local population of Asian Arowana, causing great declines in number. IUCN notes that the Arowana population density has been very low, with great declines of much more than 50% wherever it naturally occurs, and that its population is still decreasing.
Destruction of natural habitats is the Arowana’s current main threat, according to IUCN. A study done in Cambodia notes that the Arowana’s habitats are being increasingly rapidly degraded by human activities and construction, such as dam building, logging, mining, and expansion of agriculture. In fact, the impact of all these human activities is probably far greater than the impact caused by local harvesters.
Of all these threats, the impact from the building of hydroelectric dams is probably the greatest. Dams have several devastating environmental impacts, some of which include trapping of sediments (important for maintaining habitats downstream), upstream transformation (deadly changes in temperature, oxygen levels in the water etc.), and disruption and alteration of the river’s flow, which can have the same devastating effect as drying up the river completely. And rivers where wild Arowana are known to inhabit have now come directly under threat.
In Cambodia, plans to build a dam in the Areng river have already been approved. The Areng river is home to one of the largest populations of Arowana in Cambodia. The Arowana is unable to adapt to the great changes brought about by the dam, and therefore this population (which exists both down- and upstream of the dam) would be unable to survive. Such a loss will be devastating for both the global Arowana population and conservation efforts that have been undertaken.