Black Arowana (Osteoglossum ferreirai)

IUCN Conservation Status: Least Concern

Ecology

Named after the striking black and orange colors it sports when young, the black arowana comes from quiet wetland streams and backwaters in South America’s Negro River basin! [1,2] As it grows older, it loses the dark color to take on a silver color like its more well-known cousin, the silver arowana. [3] Like many other fish in this region, the black arowana is adapted to drastically changing water conditions as its habitat experiences intense differences in water levels during the wet and dry seasons, and can be found swimming in the forest during the wet seasons. [2] Like all arowanas, this fish likes to swim near the surface of the water, and will jump out of the water to catch small insects and fish. [2] Although it starts small, the black arowana can grow to be over 3 feet long, and has a fascinating breeding process. This fish is a mouth brooder, and a male arowana will carry fertilized eggs in his mouth until they hatch. [2]

Fishery

This fish is harvested at a small scale for aquariums, and is typically on the rarer side. [2]

In Aquaria

As a large fish, the black arowana should be kept in a space that gives it plenty of room to move and swim, and a lid should be placed to prevent it from jumping out of the tank. At least a 600 gallon tank is needed to keep this fish when it is adult size. The black arowana should be fed with live/frozen foods on the surface of the water, and it prefers soft water that mimics the tannin* filled waters it comes from. It also needs warm water, so use of a heater is necessary to keep the water between 75-82 degrees F. Although it is not particularly aggressive, this fish will attack smaller fish and members of its own family and should only be kept with similarly-sized fish.

Tannin: yellow/brown organic substances produced by some plant tissues. Tannins are good for many freshwater fish species and are used to create ‘blackwater’ tanks. Tannins are also found in your tea and wine, but don’t add those to your aquarium!

Citation

[1] Ferraris, C.J. Jr., 2003. Osteoglossidae (Arowanas). p. 30. In R.E. Reis, S.O. Kullander and C.J. Ferraris, Jr. (eds.) Checklist of the Freshwater Fishes of South and Central America. Porto Alegre: EDIPUCRS, Brasil. Accessed on Fishbase.

[2] Reis, R & Lima, F. 2009. Osteoglossum ferreirai. The IUCN Red List of Threatened Species 2009: e.T167687A6367885. https://dx.doi.org/10.2305/IUCN.UK.2009-2.RLTS.T167687A6367885.en. Accessed on 02 September 2022.

[3] Black Arowana - Osteoglossum Ferreirai - Tropical Fish Site. (n.d.). Retrieved September 2, 2022, from https://www.tropicalfishsite.com/black-arowana-osteoglossum-ferreirai/