The Natural Habitat of Piranhas
Piranhas only exist in nature in South America.
And has never been introduced in any other place neither
by accident nor deliberate.
The natural ranges of the Piranhas are (se map above) the
Orinoco, the Guyana, the Amazon, the Rio Sao Francisco,
the Rio Paraguay and the Rio Parana.
The majority of Piranhas live in the so called whitewater
rivers. A whitewater river carries loamy water with a great
deal of fine particles in suspension thus giving it a milky
Some Piranhas live in the poor blackwater rivers and
some in clearwater rivers. But in these cases they
live near where two rivers meet and white- or blackwater mix
In general Piranhas are amazingly tolerant to different water
conditions. They live in rivers with a temperature of 24 - 30
degrees C (75 - 86 F).
Piranhas in the Ecosystem
Why are there only Piranhas in the South America? The most
likely reason is a phenomenon called the Pororoca. This
happening occurs only in the South American rivers due to their
relief conditions. 3500 km from the mouth, the Amazon flows at
an altitude of just 150 m. Compare this with the Congo that
lies at an altitude of 400 m. The result is that the tide rises
into the rivers, several hundred km. The masses of freshwater
offer an increasing resistance to the saltwater until the
compressed mass 'explode'. Thunderously the waters rise to a
6 to 8 meters high giant wave, that rolls towards the ocean.
This is the Prororca!
The Prororca kills a large number of animals and leaves the
waters filled with cadavers. Now the Piranhas come into the
picture as the only fast-acting underwater health squad
available. Without the Piranhas the amount of contagious
diseases would be tremendous.
Of course Piranhas attack living creatures as well. Specially
when hungry, for example if they have been trapped in a
drying lake. Like hyenas, Piranhas sometimes hunt on their own
and like them they not only feed on dead animals, but attack
everything that is sick, weak or unfit to live long.