Black Pacu

Colossoma macropomum

A big, gentle, fruit-eating Amazon fish related to piranhas, also called the tambaqui.

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About the Black Pacu

Black pacu can reach 3 feet long and weigh over 65 pounds. They are tall, narrow, plate-shaped fish that move easily between water plants. They live in the upper Amazon River basin. They eat fruit, plants, decaying plant matter, snails and other foods, and they always seem to include plants in their diet.^[1]

Quick facts

Scientific name: Colossoma macropomum^[1]
Size: Up to 3 feet long.^[1]
Weight: Over 65 pounds.^[1]
Lifespan: About 15 years.^[1]
Diet: Mostly fruit and plants, plus snails and other foods.^[1]
Habitat: Rivers; young live among floating plants.^[1]
Where it lives: The upper Amazon River basin.^[1]
Babies: Young live in floating plants.^[1]
Conservation status: Near Threatened (IUCN Red List, assessed 2020).^[2]

Fun facts

Pacu are fruit-eating cousins of piranhas.^[1]
Pacu are darker underneath and lighter on top, the opposite of most fish.^[1]
Pacu can weigh more than 65 pounds.^[1]

Vocabulary

fish: A cold-blooded animal that lives in water, breathes with gills and usually has fins and scales.
freshwater: Water that is not salty, like most rivers and lakes.
countershading: Coloring that is dark on top and light underneath, which helps an animal hide.
frugivore: An animal that eats mostly fruit.
near threatened: A conservation label meaning a species may soon be at risk of dying out if things don't improve.

See it in person

Smithsonian's National ZooWashington, D.C. · AmazoniaSee this animal on the zoo's website ↗

These zoos had this animal when we gathered our information, but animals sometimes move. Check the zoo's website or contact the zoo before you visit.

Sources

[1] Smithsonian's National Zoo & Conservation Biology Institute. “Black pacu.” https://nationalzoo.si.edu/animals/black-pacu (accessed 2026-10-08)
[2] IUCN Red List of Threatened Species. “Colossoma macropomum (Tambaqui).” https://www.iucnredlist.org/species/49830760/85567354 (accessed 2026-10-08)

Facts last checked 2026-10-08.

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