Habitat – river and flooded forest
Niche – large predatory fish
Favorite Food – small fish
Length – up to 15 feet
Weight – lunkers up to 500 pounds
Status – Vulnerable
Threats – overfishing, loss of habitat, pollution
The creature of the black lagoon isn’t a man in a green costume that grabbed swimsuit-clad women. It’s a fish. In the blackness of the Amazon, the biggest freshwater fish in the world still lurks, though in numbers far fewer than even 20 years ago.
The Arapaima gigas or pirarucú is the largest predatory fish living in the Amazon River basin. Like pike in the American Midwest, the lunkers of the Arapaima gigas inspire fearsome awe. The most spectacular specimens have measured close to 15 feet and weighed in at 450 pounds or more. Unlike most other fish, only the very young pirarucú have gills. The adults must instead breach the surface of the river and draw air into their lungs through their mouth – a method more common to aquatic mammals than fish. Insatiable predators, they lunge at smaller fish with powerful jaws and a toothed tongue that acts as a third set. They don’t get so big for nothing.
Pirarucú are very important fish in Brazil. Yet it is because of their importance that their numbers are suffering. Few creatures that yield delicious steaks are spared the eye and gullet of mankind. Once common in wide swaths of the Amazon, populations of Arapaima gigas are shrinking due to overfishing, loss of habitat, and pollution. Because fewer fish are left to live for 10 years or more, very large pirarucú are fast becoming legend in all but the most remote sections of the river. When fishing outpaces the fishes’ ability to produce enough offspring surviving to adulthood, populations can crash and have crashed. The future of this giant is still rife with any number of possibilities.