Silver ArowanaOsteoglossum bicirrhosumWhere and when to see them

The silver arowana is a large freshwater fish native to tropical South America, including the Amazon Basin. It is a surface-oriented predator with an elongated body, large metallic scales and an upward-facing mouth. Its ability to leap from the water helps it capture prey above the surface. Despite its global Least Concern status, it is caught for food and the ornamental fish trade, making responsible local management important.

Size

Up to about 1.2 m long, although most individuals are smaller.

Weight

Up to about 6 kg.

Lifespan

Can live for more than 10 years in captivity; lifespan in the wild is poorly documented.

Status

Least Concern (IUCN).

Silver arowanas usually cruise just beneath the surface, moving with slow, flowing strokes of their long fins. They search for prey along sheltered banks, floating vegetation and overhanging branches. A sudden acceleration may end in a leap to seize an insect or other small animal above the water. Individuals are often encountered alone, although several may use the same productive feeding area. Their movements follow changing water levels, allowing them to enter newly flooded habitats. During reproduction, the male gathers the eggs into his mouth and broods them there. He continues protecting the young in his mouth during their early development.

• The male carries both eggs and newly hatched young in his mouth.
• Its two chin barbels help give it a distinctive silhouette.
• It can leap out of the water to capture prey above the surface.
• It belongs to the bonytongue fishes, named for their toothed tongue bones.

Wildlife opportunities depend on the river reach, water levels and species. River-specific viewing months have not been confirmed; general species seasons are not a local sighting forecast.

In the Amazon Basin, silver arowanas inhabit slow-moving river margins, floodplain lakes, backwaters and flooded forests. They are especially associated with sheltered surface waters near vegetation. Seasonal flooding opens access to forest edges and other habitats rich in food. As water levels fall, fish become restricted to permanent lakes, channels and other remaining waters. They occur in different Amazonian water types, rather than being confined to a single kind of river.

Silver arowanas are opportunistic carnivores that eat fish, insects, crustaceans and other small animals. Terrestrial insects falling onto the water can be an important food source. They also take prey from low vegetation by leaping above the surface. Small vertebrates such as frogs may be eaten when available, but spectacular accounts of larger prey should not be treated as typical feeding behaviour.

Common name

Silver Arowana

Scientific name

Osteoglossum bicirrhosum

Animal group

Fish

Size

Up to about 1.2 m long, although most individuals are smaller.

Weight

Up to about 6 kg.

Lifespan

Can live for more than 10 years in captivity; lifespan in the wild is poorly documented.

Status

Least Concern (IUCN).

Identification

Look for a long, laterally compressed body covered in large, silvery scales. The upward-facing mouth has two distinct barbels projecting from the tip of the lower jaw. Long dorsal and anal fins extend along the rear of the body toward a relatively small tail fin, producing a ribbonlike outline. Juveniles can show darker markings and more colourful fins, so colour alone is less reliable than body shape and fin arrangement.