Piranha Report from 3rd Grade

Back when I was in 3rd grade, we were assigned to do a big animal report.  My animal was the piranha.  For the report, I had to do research about the piranha and write a report that included its habitat, predators and prey, reproduction, adaptations and cultural impact.  We also had to make art about the animal.  I made a model of a piranha using Model Magic on top of a base made of plastic plates.  I used buttons for the eyes and a plastic milk jug cut into pointy pieces for the teeth.  I painted it with acrylics. 

I also wrote a poem . . .

And I made a diagram with watercolors...

And a comic about a piranha feeding frenzy...

Here is the text of the report: 

Description:
One of the most amazing animals is the piranha.  The word piranha means "toothed fish" in the Tupi language.  Another name for piranha is "Caribe" which means "cannibal."  There are 30 different species of piranha.  They all belong to the Serrasalmus family.

Piranhas are a cold-blooded, fresh water fish.  They breathe through their gills.  They swim in schools and they are omnivorous.

A piranha has a round, flat plate-shaped body and a stubby, bulldog snout.  Piranhas are also marked with red, green or black markings, and the older they get, the more colorful they become.  Piranhas are usually 6-10 inches long, but some can grow to 24 inches.  Their most notorious feature is their small, triangular, razor-sharp teeth. 


Diet:
A piranha is an omnivore. It eats flesh, except it usually eats dead or dying flesh.  Normally, they don't attack live prey.  However, in the dry season when food is scarce, piranhas are aggressive and will attack other animals. 

They hunt in schools.  When many piranhas attack, it is called a feeding frenzy.  They eat quickly to get as much as they can. 

Some of the things that piranhas eat are: each other (if desperate), seeds, fruits, insects, shrimp, birds, rodents, reptiles and the scales, tails and fins of other fish. 

Piranhas have the reputation as man eaters, but it is not true.  There are no reports of any human being killed by piranhas.  Sometimes, they eat the dead bodies of people that died of other causes. 

Habitat:
The piranha lives in the low land tropical rivers of the rainforests of South America.  Piranhas live in the major rivers, streams and lagoons of: Venezuela, Brazil, Bolivia, Paraguay, Argentina and Uruguay.  They live in rivers that lead to the Atlantic Ocean, including: the Amzaon, Orinoco, Essequibo, Lapata and Sao Francisco rivers.  Since it's a fish, it makes a nest in the mud in breeding season.

Reproduction:
Like all other fish, piranhas spawn to reproduce.  "Spawn" means to lay eggs.  Piranhas mate in the rainy season.  Piranhas change color in breeding season to attract mates.  Piranhas attach their eggs to floating plants or lay them in a nest they make in the mud.  Both parents guard the nest from predators. 

Little is known about baby piranhas.  When baby piranhas hatch, they are independent.  Their parents do not take care of them.  Babies are about one inch long.  They hide and hunt in the roots of squatic plants.  Since piranha babies are so small, they are vulnerable to predators.  If they survive, they live about five years.

Adaptations:
Here are some adaptations the piranha uses to survive.  It has gills so it can breathe underwater.  It also has scales to let it swim faster.  Adult piranhas have few predators.  South American crocodiles, or caimans, and the wide-mouthed catfish can swallow a piranha whole.  No other wild animals mess with piranhas.

The piranha has many structural adaptations to obtain food.  Its sharp, triangular teeth rip flesh.  To keep their teeth sharp, they grow new teeth throughout their lives.  Their lower jaw is bigger than their upper jaw and it closes like a trap.

The piranha has a strong sense of smell.  It can smell a drop of blood in 50 gallons of water.  Taste buds cover its body to sense if there is something good to eat in the water.  They also have a lateral line, which are small hairs and pores on their sides.  It can sense vibrations in the water which alerts them to predators or prey.

Piranhas also have behavioral adaptations to  help them get food.  They swim in schools and they will attack prey together.  This is called a feeding frenzy.  In a feeding frenzy, piranhas swarm the prey, but they rotate and take turns biting so every piranha gets some of the food. 

Other:
Piranhas help people by being a source of food.  People fish for piranhas, but piranhas can be a problem for fishermen because they eat the bait and the catch. 

Piranhas help keep the water clean by eating dead animals.  During the flood season, people can't bury their dead. So they leave the bodies in the water and the piranhas eat the flesh.  Only the bones are left, which are decorated and then buries after the flood.  This is how piranhas are part of the native culture. 

The natives use the piranhas' jaws as a cutting tool.  In fact, their word for scissors is "piranha."

Piranhas are not on the endangered list, since they have few predators. 

Piranha can be seen in San Francisco at the Academy of Sciences in the rainforest exhibit.  They are in a separate tank so that they do not bite or hurt any other fish.  The Academy also has a dried piranha in the Naturalist Center. 

There have been several horror movies about piranhas.  One of them was called "Piranha."  It was made in 1978.  In these movies, piranhas are exaggerated as man eaters.  Even though this is not true, they are ferocious.