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Black Piranha: Freshwater Species of the Week

Piranha showing teeth in pantanal
Piranhas are legendary for their sharp teeth and strong jaws. Photo: Brian Clark Howard


Updated December 23, 11:45 pm

Long famous for their fearsome appearance and sharp teeth, piranhas can add another accolade to their storied reputation as formidable predators. The black piranha (Serrasalmus rhombeus) has been recognized for having the strongest bite among living fish, pound for pound, according to research by Justin R. Grubich, Steve Huskey, Stephanie Crofts, Guillermo Ortí, and Jorge Porto.

Among extinct fish, the megapiranha is now thought to have the strongest bite.freshwater species of the week

The new research paper, Mega-Bites: Extreme jaw forces of living and extinct piranhas, is published in Scientific Reports, andhighlights the piranhas’ specialized jaw morphology, which allows them to attack and bite chunks out of much larger prey,” according to George Washington University, where Guillermo Ortí teaches.

There are about 20 known species of piranha in South America, and the black piranha is the largest of the carnivorous types. The fish’s bite strength had not been measured before. Orti and colleagues discovered that the fish can bite with a force more than 30 times greater than its weight.

“The powerful bite is achieved primarily due to the large muscle mass of the black piranha’s jaw and the efficient transmission of its large contractile forces through a highly modified jaw-closing lever,” reported the university’s press office.

 “The authors also reconstructed the bite force of the megapiranha, showing that for its relatively diminutive body size, the bite of this fossil piranha dwarfed that of other extinct mega-predators, including the whale-eating shark and the Devonian placoderm. Research at the Ortí lab at GW continues to focus on reconstructing the genealogical tree of fishes including piranhas based on genomic data.”

So although piranha might not be quite as fierce as Teddy Roosevelt thought in 1913, they can still cause some damage.


Guillermo Orti piranhas
Guillermo Orti studies piranhas. Photo: George Washington University


Brian Clark Howard covers the environment for National Geographic. He previously served as an editor for TheDailyGreen.com and E/The Environmental Magazine, and has written for Popular Science, TheAtlantic.com, FastCompany.com, PopularMechanics.com, Yahoo!, MSN, and elsewhere. He is the co-author of six books, including Geothermal HVACGreen LightingBuild Your Own Small Wind Power System, and Rock Your Ugly Christmas Sweater.


  1. jose peroza
    achaguas, apure venezuela
    January 4, 2013, 3:16 am

    In venezuela two species of piranhas, piranha black (pinche) and piranha red (caribe)

  2. Sameer mahajan
    December 26, 2012, 3:54 am

    though I’m also having black piranhas but it;s not so aggerasive lives very friendly with 2 other species( twin fin bar and black shark)

  3. Dennis
    Iquitos, Peru
    December 23, 2012, 11:56 am

    I like this article, it is going to educate to a lot of people that had been misinformed about the “ferocious” nice piranha. Well no that nice.

  4. Ima Ryma
    December 23, 2012, 4:36 am

    The black piranha, I’m now known
    For the strongest bite among fish,
    Pound for pound, some research has shown,
    By some human who had a wish
    To measure the strength of my bite,
    Which is 30 times more in force
    Than my weight, which is kind of light.
    The guy was in my face of course,
    A fiddling around with my jaw,
    Impressed by its efficiency.
    Humans get easily in awe,
    But so annoying, they can be.

    The human learned this at a cost.
    The finger poked at me – ’twas lost.

  5. Justin Grubich
    December 23, 2012, 1:15 am

    Shoddy reporting. Try reading the primary source.

    • Brian Clark Howard
      December 26, 2012, 4:43 pm

      Hi Justin. I updated the post to reflect the complete list of study authors, sorry you were omitted at first.

  6. Jim
    Semi-Free States of America
    December 23, 2012, 12:58 am

    I think I saw another news article about one of these getting loose from a stream in Chicago and ended up in the Potomic River,,somewhere near DC.

  7. Michael T. Lemen
    New Port Richey Florida
    December 22, 2012, 11:47 pm

    OW !!! Those teeth look painful. I don’t which would be worse being eaten whole by Jaws or little bite by little bite by little bite until you bleed to death

  8. pbparksLUVfishYUM!
    December 22, 2012, 11:43 pm

    Aside for my luv 4 fish, Truly, I ask this because of potential future food shortages for various reason (some yet to be discovered & revealed as potential game stoppers for human diet ). Agriculture is not free from world wide disasters. Is the piranha a potential major food source for their regions of habitat ? They look to be clean & abundant. Do they already make up a large part of any human groups diet ? Those two, that Mr.Orti’s holding, look mighty meaty & Yummy too ! WOW ! I really do luv fish. As long as they taste good. I need to watch more National Geographic. You folks do a fine job in all your works & reports. Thanks ! pbp…

  9. pbparksLUVfishYUM!
    United States
    December 22, 2012, 10:27 pm

    All i wanna know…is they good eatin’ ?

  10. Mary
    December 22, 2012, 7:16 pm

    GOD’s amazing creation. So much we need to learn.