The Piranha, Serrasalmus piraya

When is a Tetra Illegal? When it is a Piranha in Florida, and for Good Reason!

Red Belly Piranha taken by Dr Thomas R, Reich In Vancouver Canada
Thomas R. Reich PhD

Piranha – “The Man-Eater of the Amazon” Is that what you think of when you hear the name Piranha?  What visions does it’s  name conjure in your mind’s eye? Surely a large, terrible-looking fish, with row upon row of sharp, vicious teeth, capable of biting a man virtually in two!

On the contrary, the Piranha averages only 10 inches in size and belongs to the friendly Characin Family, that’s right; it is a cousin of the Neon!

  Its appearance certainly belies such a forbidding name, and with more than 18 known varieties and species of Piranha, they span the spectrum from vicious gang killer, to peaceful scavenger, no more violent than a convict cichlid on a good day!


TRACKING THE SPECIESThe name Piranha applies loosely to about 18 species, of which only 4 seem to be dangerous to humans.  All are members of the genus Serrasalmus, having a general similarity of appearance and habits.  Some scientists, however, classify them differently.  Most of the species average 8 inches in length but Serrasalmus piraya of the River Sao Francisco in eastern Brazil, one of the most dangerous, may reach 2 feet.  Most Piranha are olive or blue-black above and silvery or dark grey on flanks and belly.  Some species have reddish or yellowish tinted fins and some have reddish or orangeish bellies.  The colors seem to vary considerably from place to place and with age.

  For example, old specimens of the white Piranha Serrasalmus rhombeus, found in the Amazon system and north-eastern South America, are often dark enough to be called black Piranhas.

However, certain varieties of Piranha are so dangerous and so violent that tributaries of the upper Amazon, which contain these fish are shunned by the natives and animals alike to this day!

  With good reason, the luckless creature that falls into these streams will meet a most violent end indeed.  Thousands of hungry Piranhas congregate at that spot and in a matter of minutes, with tiny bites no bigger than a sugar cube, they reduce the body of a full grown cow to a skeleton in minutes.

In the wild, their insatiable appetites cause them to fight with one another, and the losers become meals for the stronger ones in a constant “survival of the fittest.”  If you really want to see what a Piranha can do, find an old group of documentaries called “Faces of Death”.  Contained therein is an actual depiction of why Piranha are illegal in the United States.  You will see a cow reduced to bones in less than 3 min, they even have more gruesome scenes that will convince you to never change that legislation.

Do you know why all Piranha are illegal in the US, especially in Florida, and why I crusade for them to be at all cost?  Because they can live and breed in the everglades, in fact they have been caught by fisherman in south Florida already.  Luckily they were the less violent species that have been caught to date, but if the more dangerous version becomes invasive, it could destroy much of what we love about Florida.

  Make no mistake about it, we fish keepers are not all responsible, and it only takes one well meaning hobbyist who orders 5 of them off the black market, decides they are too much trouble to keep and lets them loose in South Florida.


PIRANHA IN THE WILD:  Piranha have insatiable appetites which cause them to fight with one another constantly, the losers become meals for the stronger ones which leaves them scarred and marked.  They are extremely prolific in their natural haunts, having up to 2000 fry per spawning and breeding season is 12 months per year and they can breed again every 21 to 28 days, if conditions are prime.  Luckily, they have never been successfully bred in captivity - or have they – see below.


PIRANHA FOR SALE IN CANADA AND ELSEWHERE:  When these fish are collected and shipped for sale, their size cannot vary more than 2 inches, as the larger Piranha would kill the smaller ones en route to the store or distributer.

  I must admit, when I was younger and growing up outside of Philly, I had 5 Red Belly Piranha, before the ban, they would eat Goldfish like peanuts, and for visitor viewing, a large Goldfish would be torn apart by all five in about 30 seconds.  I had over 70 Aquariums in my hobby room in my youth and carried on many responsible experiments, but I still do not think anyone should ever own these fish in a private home.


HOW TO HAVE A PIRANHA LOOK ALIKE:  Buy a Red Belly Pacu, I do not recommend them, because as a juvenile they very much resemble the Red Belly Piranha, in fact they are extremely close relatives.  The Pacu is mostly vegetarian and is definitely not dangerous, but within a year it will begin to grow so big, that no matter how big the tank you put it in, it will grow too big for that tank.  One final note, after about 10 inches or so, it no longer looks like the Piranha, the Pacu just looks like a very unattractive very big very crowded very unhappy fish.


FEEDING PIRANHA:  All species of Piranha require a high protein diet, taking meat, liver, fish, or any other flesh, which will satisfy their insatiable need and constant hungar.  They cannot eat and will not accept flake or pellet food.  They will seize and devour any fish of any size introduced to their tank, gulping small fish whole, and slashing out large pieces from larger fish, not even hesitating to attack and eat fish 3 times their size as soon as they are introduced to a tank they are in.


PIRANHA BRED IN AQUARIUM:  It turns out that in breeding, the Piranha is uncharistically parental for a Characin.  In nature many species use water plants as hatcheries.  It is thought that Piranha breed when the rainy season sets in about January or February, but they seem to breed whenever conditions are right and water plants are plentiful.  The female deposits her eggs on water plants or roots, which are then fertilized by the male.  On hatching, the fry stay attached to the vegetation in clusters until they have absorbed most of the yolk sac, and then become free-swimming.

  The male will attack anything coming close to the fry during this state, which is why, some scientists theorize, natives get bitten but not killed in some streams.

Serrasalmus spiopleura is one of the few species which actually has been seen breeding in an aquarium.  The female deposited her eggs carefully on aquatic plants, which is unlike the usual erratic spawning behavior of most of the Characin family.  The male guards the eggs as well as the fry!  This is a Characin we are talking about here, until a full 5 days after the fry have hatched absorbed their yolk sac and are free swimming.  To top it off, the parents then ignore the fry, they do not chase or eat them, and the fry were seen swimming around the adults, one must assume in the wild guarding must continue almost cichlid style.  One final note, the Piranha will viciously guard their eggs which includes biting the hand that feeds them, the breeder ( and I certainly hope you are not in possession of Piranha or breeding them) will be bitten if you put your hand anywhere near the water!


PERSONAL AQUARIUM STORY:  Back when it was legal to own these unusual fish, these ferocious fish adapted readily to aquarium conditions.  Until a federal law was passed forbidding the importation of Piranhas of any kind (a law I agree with) they were frequently seen in private collections (mine included) and most prominently on display in pet stores with the usual skeleton in the tank and a sign “Terrible Cannibal Fish of the Amazon”.  However, more than a few families entered the pet store to see the Piranha, and left with a new aquarium and a new hobby for the family.  Sadly, not as many families are starting our great hobby today and I wish more would!

Despite the law, a few Piranhas of various species still find their way into the aquariums of hobbyists here in the US and around the world, for the average customs inspector is totally incapable of distinguishing the Piranha from a dozen other fish that are commonly imported from South America.  Add to that, both US border neighbors Canada and Mexico have no laws against Piranha and some come over the border that way.  If you have a Piranha, be careful.  If you get tired of it kill it, do not put it in a natural waterway, you are not being cruel, you are being cruel not to kill it.  Do not destroy our wild waterways with the very worst of invasive species.

The reality is that Piranha are not all that fun to have in an aquarium, they are expensive to feed, rather ugly to look at and not very active.  Curiously, in an aquarium, Piranhas often become quite shy.  Except for an occasional glimpse of those horrible teeth, there is little to indicate their wild characteristics at all.

In captivity, Piranha’s are usually fed live fish and worms; they prefer their food on the move.  When a small fish is placed in the aquarium, the Piranha looks it over with studied deliberation, in other words for a very long time it just sits there.  Then, with a lightning-fast dash, the hapless fish is seized from the rear and neatly clipped in two.  The forward portion may be eaten next, or may be left to die in a few minutes of agony.  So long as half of a fish keeps struggling, the Piranha may take another bite.  Once the feeder fish is dead, it is usually ignored and will rot if not removed.

I am sure that in all the world of fresh water fish and most of the salt water fish of the world, there is more efficient killing machine.  There is certainly nothing more efficient at clear cut biting than the South American Piranha.  Even the much feared sharks of the deep blue sea cannot cut a body down to size so quickly, displaying such team work and with such efficiency as the Piranha!


WHERE IS IT LEGAL TO OWN SOME SPECIES OF PIRANHA?:  It is legal to own piranhas in some states including Michigan, New Hampshire, Delaware, Illinois, Indiana, Kansas, Maryland, Minnesota, Missouri, Montana, Nebraska, New Jersey, North and South Dakota, Oregon, Pennsylvania, Rhode Island, Tennessee, Vermont, West Virginia, Wyoming and Wisconsin. Their sale and possession is banned or regulated in Alabama, Alaska, California, New York, Arizona, Arkansas, Hawaii, Florida, Colorado, Kentucky, Maine, Georgia, Louisiana, Nevada, New Mexico, Mississippi, Utah, Texas, Washington, North and South Carolina, Oklahoma, Virginia, Idaho, Connecticut and Massachusetts.


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