Salmoniformes › Salmonidae
Sockeye salmon
Dies after one spawn
Some sockeye never reach the sea and live their whole lives in a lake.
Field Guide · Chapter 14 of 29
Freshwater fish
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Salmoniformes › Salmonidae
Rainbow trout
Lake fish up to 9 kg
People have carried it to at least 45 countries for food or sport.
Salmoniformes › Salmonidae
Brown trout
18 to 56 cm long
Brown trout were introduced worldwide as a game fish, and became one of the world's worst invasive species.
Cypriniformes › Cyprinidae
Goldfish
Up to 45 cm long
Let loose in the wild, goldfish slowly turn back to yellow-orange.
Perciformes › Centrarchidae
Largemouth bass
Up to 75 cm long
In this bass the female is usually bigger than the male.
Esociformes › Esocidae
Northern pike
Up to 150 cm long
Some juvenile pike have choked to death on a fellow pike of similar size.
Siluriformes › Siluridae
Wels catfish
Heaviest: 134.97 kg
It can swim backwards, like an eel.
Perciformes › Cichlidae
Nile tilapia
Up to 60 cm long
Males and females eat the same amount, yet males tend to grow larger, turning food into weight better.
Characiformes › Serrasalmidae
Red-bellied piranha
Up to 3.9 kg
Despite its reputation as a ferocious predator, it is mostly a scavenger.
Gymnotiformes › Gymnotidae
Electric eel
Up to 2.5 m long
Nearly eighty percent of its oxygen comes from air it gulps at the surface.
Osteoglossiformes › Arapaimidae
Arapaima
Commonly 200 cm long
It has to come up for air every 10 to 20 minutes.
Acipenseriformes › Acipenseridae
Beluga sturgeon
7.2 m long, a record
The beluga sturgeon is the largest freshwater fish in the world.
Perciformes › Osphronemidae
Siamese fighting fish
Rarely over 15 minutes
Wild bettas are drab. The bright reds and blues come from selective breeding.
Cypriniformes › Cyprinidae
Zebrafish
Hundreds of eggs
Its major organs begin forming within 36 hours of fertilization.
Cyprinodontiformes › Poeciliidae
Guppy
Females 3 to 7 cm long
Guppies have been introduced to every continent except Antarctica.
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