Puppy-Size Tarantula Found: Explaining World’s Biggest Spider

The world’s largest spider has crept back into the spotlight, thanks to a scientist who describes a harrowing encounter with a tarantula.

Harvard entomologist Piotr Naskrecki recently recounted on his blog coming across a puppy-sized, foot-long (0.3-meter) South American Goliath birdeater (Theraphosa blondi) a few years ago in Guyana (map).

“I could clearly hear its hard feet hitting the ground and dry leaves crumbling under its weight,” Naskrecki wrote about his nighttime run-in.

“I pressed the switch and pointed the light at the source of the sound, expecting to see a small mammal, a possum, a rat maybe. And at first this is what I thought I saw—a big, hairy animal, the size of a rodent.” (Watch a video of the world’s biggest spider eating a mouse.)

Instead it was a specimen of T. blondi, a tarantula whose weight can reach six ounces (170 grams). Last Halloween, Carrie Arnold wrote an explainer about this monster of the spider world, which we’ve drawn from for this article.

Commonly known as the Goliath birdeater due to an 18th-century engraving showing another member of the tarantula family eating a hummingbird—which gave the entire Theraphosa genus the nickname of “bird eaters”—the gargantuan spider is not quite as menacing as it might seem, Arnold reported.

Gentle Giant

Despite its nickname, T. blondi only rarely devours birds. According to spider expert Gustavo Hormiga at George Washington University, T. blondi mostly eats arthropods.

“They are general predators, and if they run into other vertebrates, like a small mouse or lizard, they can eat those too,” Hormiga said in 2013.

But don’t expect this Goliath to use a giant web to snare its prey. T. blondi hunts for its meals the old-fashioned way—using its large fangs to bite and kill. (Watch video: “How to Survive a Giant Tarantula Encounter.“)

Like most spiders, T. blondi produces venom, although Hormiga notes that it’s not particularly toxic to humans.

The bites, which have been described as feeling like wasp stings, almost never require medical attention.

Beware the Hair

Although T. blondi doesn’t weave a web, it does produce and use silk. The spider lives in burrows beneath the forest floor, which it lines with silk to give the structure more stability. Should a mammal try to dig up the burrow for a tasty spider snack, T. blondi has a weapon more useful than venom: urticating hairs on its abdomen.

(The technical term is “bristles,” as only mammals have hair, but even scientists use the more popular term in conversation.)

“These are shaped like little harpoons if you look at them under the microscope,” Hormiga said, which gives the hairs the ability to embed in the skin.

“These spiders very quickly rub their fourth pair of legs on their abdomen to release the hairs, which then become airborne. These are very itchy.” (Related: “Tarantulas Shoot Silk From Feet, Spider-Man Style”)

The urticating hairs don’t need to be airborne to do their damage, however—researchers and owners of pet spiders need to handle the Goliath birdeaters with gloves. To large animals like humans, the hairs are merely irritating and itchy, but they can be fatal to smaller mammals like mice.

Naskrecki had a firsthand experience with these hairs—and the damage they inflict.

“The spider would start rubbing its hind legs against the hairy abdomen,” he wrote on his blog. “‘Oh, how cute!’ I thought when I first saw this adorable behavior, until a cloud of urticating hair hit my eyeballs, and made me itch and cry for several days.”

T. blondi females lay between 50 and 150 eggs in a giant sac that can measure over an inch (30 millimeters) in diameter. They cover the sac in urticating hairs to keep predators away.

It takes about two to three years for these hatchlings to mature; they spend significant time living with their mother in her burrow until they’re old enough to fend for themselves. Although females can live up to 20 years, males have a life span of only three to six years, often dying soon after reaching maturity and mating.

Tastes Like Prawns

Many of the locals in northeastern South America regard T. blondi as a tasty snack. They first singe off the urticating hairs, then wrap the spider in banana leaves to roast it. Tarantula expert Rick West, who once sat down for a meal of these spiders with the local Piaroa people of Amazonas in Venezuela, says T. blondi can be surprisingly tasty and moist. (Also see “UN Urges Eating Insects; 8 Popular Bugs to Try.”)

“The white muscle ‘meat’ tastes like smoky prawns, while the gooey abdominal contents is hard-boiled in a rolled leaf and tastes gritty and bitter,” West says. “The three-quarter-inch [two-centimeter] fangs are used after the meal as toothpicks to remove T. blondi exocuticle from between one’s teeth.”

It’s not often that your dinner comes with built-in toothpicks. Despite the Goliath birdeater’s  shrimplike taste, however, you probably won’t see it on a restaurant menu anytime soon.

As for Naskrecki, he wrote he was “ecstatic about finally seeing one of these wonderful, almost mythical creatures in person.”


Christine Dell'Amore, environment writer/editor for National Geographic News, has reported from six continents, including Antarctica. She has also written for Smithsonian magazine and the Washington Post. Christine holds a masters degree in journalism with a specialty in environmental reporting from the University of Colorado at Boulder. Her book, South Pole, was published in 2012.
  • Aabish Qureshi

    Whoa! The video was scary,it gave me the creeps and also it was VERY fascinating because it was talking about the biggest spider on earth. But the video still gave me the creeps though this article is very awsome!!!!!!!!

  • Jayanta

    Arachnophobia is very common…although I have managed to get rid of the fear for most arachnids….large spiders and scorpions still freaks me.

  • Andrew

    Bird-eating spiders certainly look alarming. Like most creatures however, they pose no threat to humans as their only concern is to go about their business in peace. It’s humans who are a threat to spiders – and that’s spoken as someone whose wife has to do the business with the glass and paper when one comes in the house!

  • Tina

    What’s wrong with people? Is this the foolish scientist that removed the beautiful spider from its home and took it to a museum? I understand the natives killing it for food. But, why didn’t he just leave it alone? I’d like to think Mother Nature will get back at him somehow. What a waste of a life!

  • Janet Yu Xu

    The scientist who took the video is very remarkable, I think. Such a big spider is scary.

  • Scott Templeman

    Tarantulas are amazing creatures that are often misunderstood and despised as a result. The Theraphosa blondi is certainly a magnificent example.

    I run the largest tarantula group on social media, with currently approximately 20,000 tarantula hobbyists and enthusiasts, offering advice, information and facts about these giants of the spider world. So, if you would like to learn more about these magnificent animals in a friendly and active group, feel free to join us at TARANTULA KEEPERS : http://www.tarantulas.tk

  • Frankus Lee

    Such a shame it was “killed” for science when we have so many in museums already and not enough in the wild.


    puppy size animals

  • Talal Siddiq

    amazing! awesome creature!

  • Sadat Abdurahman

    awesome creature ………the hairs the ability to embed in the skin…….amazing Females can live up to 20 years, males have a life span of only three to six years.

  • Sadat Abdurahman

    Amazing spiders and scorpions still freaks me.

  • rebecca adams

    I just got done learning about spiders but my mom use to have a pet tarantula my mom got her vanes out and her poisons out and my mom pet spider got bigger and bigger we had to buy a big change for her the spiders name was Bella and I fed her dead rats everyday and that was disgusting for me

  • Tarcisio Santos de Salles

    About the biggest spider in the world, I have personally a singular experience from years I lived in my mother’s born city, Bom Jesus, Piaui. I never saw another spider so biggest than that I saw in a certain night, in my recent new address house’s bathrom. “Incredible”! I was going to bathrom by 11:30 pm, when, after turn on the corridor’s light, I then saw it in the floor distant from me only around a meter! I’m only with a sandal and brief, with a big dark spider with a diameter of about 35-40 centimeters… A tarantula specie… Both then standed and quiet, I then worry and thinking in a manner to dominate it, remembering about some broom or a squeegee I could use to improve it… Stopped… When I discretly moved myself to look for some option around, the spider in a quick action got away to the wall behind it and in a minuscule cavity was out of my view… An extraordinary experience, unforgettable. In the follow day, I looked for some place I could meet it newly out home. However without any useful reference to hunt it… I’ve moved to that house just in that day… A house in a centered place in the small city, and with bad cleaning cares by its last inhabitants… I never saw any spider of that dimension…! Nor in Butantan Institute in Sao Paulo nor in any National Geographic or other eminent environmental research institution documentaries… An incredible, an extraordinary big spider… The biggest of world I never saw equal…

  • Seb

    Whoa the spider scar me is very interesant this is awsome

  • Anomynous

    I think the video was fascinating, how the tarantula caught that mouse was remarkable. I really do think that spiders, wolves, sharks and other animals feared by humans are just trying to live in peace. The only thing that scares me is if I accidently threaten the tarantula and get those barbs in my skin.

  • priya

    oh my god

  • Steve


    No. Freaking no. Nope. Uh-uh. Spider fit for a .45 hollowpoint right there.

  • carl eatwell

    Excellent videos as usual

  • Harleygurl

    Nope, nope, nope! I wouldn’t know how the bite feels, I’m not going to the rainforest! Matter of fact there are enough big creatures in S. Florida. Everything is bigger here! Lol

  • Jackson Arnold


  • Dave Gerrard (entomologist and herpetologist)

    The female commentators last words are along the lines of “we should not fear these creatures”. It’s VERY difficult for people to change their opinions of Arachnids, when nature video makers continue to use “horror” style music as a background to the visual. The “stalking creepy music” does no favours at all to those already “freaked out” at spiders and other arthropods.

    I have spent many years studying these, and hold a degree in Entomology including the Taxonomy of Arthropods. I study spiders, scorpions, ticks, mites and many things that people shudder at the thought of.

    In my living room, amongst my arachnid collection, I have a large Goliath female (T. Blondi). She’s been with me coming up 10 years and has never been mated.

    I can tell you from experience that the bite from this spider (the Goliath) is VERY painful. It was akin to stabbing myself on the back of the hand with an ice pick. It’s a darn site worse than a bee or wasp sting. You can still go into anaphylactic shock with the envenomation if you are allergic to bites and stings.

    Overall, these are fascinating creatures to observe. Every move they make is deliberate, and to watch one moult (shed) their old exo-skeleton turns me into an “expecting parent”. I pace the floor as she flips on her back, and remains motionless for hours and hours. The longest moult (shedding) my Goliath spider took was 13 hours from start to finish. When she finished, she flipped over onto her feet and a brilliant orange/rust brand new spider was there. All her hairs replaced, and as with every moult, she was that little bit bigger than the last time.

    Leg span on my Goliath is about 10.6 inches. She NEVER gets taken out of the enclosure, and never gets handled. It keeps her stress free. For a large spider, they can move REALLY fast, and can run across the floor of the enclosure faster than I can put a tub over her to catch her.

    Captive tarantulas (where people keep them) allow their spider to drink water – but this water must be in the form of soaked cotton wool, or other water holding medium, as a spider can drown if given plain water in a dish.

    To watch a spider wash itself after a meal is amazing. They are like cats, very clean animals, and they wash one foot and leg at a time. To finish, they wash their mouthparts, and it’s again, just like watching a cat wash it’s face.

    Spiders are NOT to be feared. People need to be educated about them in a positive way.

    And National Geographic (along with other nature documentary makers) always show good footage, but fail when it comes to the background music.

    Ok, it’s not possible to have bouncy Disney style music with spiders and snakes, but something more appropriate would be welcome, rather than the scary “Jaws” style horror music.

    Regards to all.

    Dave Gerrard

  • David Griffin

    I grew up in Florida, and spiders were just a way of life. Golden orb weavers being the most intimidating to me, even as an adult. But I lived, and worked around them daily. Mostly golden orb weavers (called banana spiders there), brown and black widows, wolf spiders, and brown recluse. Of them all, I’m really only scared of the recluse due to their roaming, and the few of them chilling in ones shoes or clothes. I eventually moved to California, and promptly met the tarantulas there. Every October the males would wander looking for mates. They were everywhere. Yet, even working outside, I was never bitten or hurt by one. They move so slowly when they’re not hunting or fleeing. I guess my point is, no matter where you go in the world, with the exception of polar regions, you will meet our 8 legged friends. Through 35 years on this planet, including being a very curious and outdoorsy child, I’ve never knowingly been bitten by one. Most of the fear is irrational, and most species won’t bother you unless provoked or trapped. If it wasn’t for these critters, we would probably be swimming in, and breathing in insects. So love them as much as your nerves will let you.
    If you truly are afraid of them, don’t ever, EVER move to Australia Trust me on that one.

  • wagner shingo tani


  • Ashley Pond V

    I agree with some other folks commenting already. Spiders aren’t scary and the scaremongering in pieces like this is harmful to people and arachnids. I used to pick up wild tarantulas and let them walk on my face because it was so amusing to see how terrified everyone was of such a harmless, shy, pleasant, retiring creature. As an adult I don’t find rabid fear of nothing at all very amusing anymore.

  • julia lupercio

    <3 im in love wit this spider it so amazing im in love with spiders <3 there so amazing they way they are and how they react to different stuff is completely wonderful

  • Jan Drexel

    It’s a pity that respiratory physiology and biomchanics put a limit on spider size, isn’t it?

  • Mel

    Spiders freak me out. Yep. But, I recognize that it is an irrational fear, so I try to abate it by watching and reading things like this. I’ve seen several large, fascinating (and revolting, to me) spiders around the world. Tarantulas don’t creep me out as much as others do simply because I’ve seen so many people handle them.

    I thank Mr. Dave Gerrard for his comments. To those that criticize humans for being afraid of spiders, come on, folks. Everyone has irrational fears. It’s up to us to face and overcome them, but don’t act like you don’t have any just because spiders aren’t hell spawn to you.

    Fascinating creatures, spiders. But, they still freak me out. Yikes.

  • som

    A statement that needs to be corrected is: “large animals like humans”. A human being is not an animal, human beings are not apes that were lucky.

  • Mark Evans

    I personally love and admire spiders. And yes I even share and understand the fear people have for them. They are nature’s perfect adaptations in our world. For their size and environment they have adapted to the top of the chain. Deep down we all know if they were even half our size we would lose as a species which is where the fear comes from. But rather than fear them, we should learn from them. They are beautiful and show us nature’s ingenuity.

  • Alex B-Z

    In reply to Som : Um, you DO realize this is National Geographic, right? Quite possibly the last place to spew that kind of homocentric crap? YES PEOPLE ARE ANIMALS. YES PEOPLE ARE APES WHO GOT LUCKY. Can you explain your assertion? That is, without reference to magic or superstition?

  • Nicodimus

    No more painful than a wasp sting, huh? There’s some misinformation…that claim may be true of the venom, but a spider with 1 inch fangs is going to do some MAJOR mechanical damage with a bite, regardless of what the venom is like.

  • Ryan Moore

    i have to agree with David Griffin on this one, as my sister has gotten over most of her arachnophobia and she is just barely below 3 years younger than I am. however, there has been a time where I was at my grampa’s for the summer and he lives in the woods, on a ridge just a little over 1mi from mine, anyway one time, I went into the bedroom where my mom usually slept when we were there and saw a scorpion in the floor creeping towards a storage closet where my grampa keeps corn for the deer and squirrels. I’m not ashamed to admit it, but I knew not to touch it or go anywhere near and immediately ran to tell my granddad it was there.

  • James

    I loved this video and so will you

  • Dr William Dunn PhD, CCP Emeritus

    Ok; here’s your chance to do some real good for both hairy eightleggers and semi -hairy two legged! Despite being a doc for yea over 40years, I’m still scared sh***es by these essentially harmless horrendeomos. Why? There are a bunch of us out here., and I wouldn’t mind being able to quit scrapping these harmless little buggers off my shoe. I feel bad about it.I confess to haveing great feelings of remorse over their demise; after all who am I to decide who lives and what dies?? I hate that feeling, but confess my shoe is locked, cocked and ready to do battle against these ugly brutes. How’s about a little more compassion for those of us who run screaming into the night when faced with a monster with a wingspan all of 6 inches?! Believe me, running into the hall and caroming into various hard objects ain’t no picnic neither. Espescilly when in your addled brain you imagine(?) Hearing this tiny voice saying “hee hee hee, got another one Marvin!!!”
    So how’s about some help? No No No don’t give me any of that “desensitvetation”crap; were here because we hate the little horrors, not because we want to crawl into a cage with one!
    Who thought that one up anyway? Afraid of fire,? howz about running up to that building that’s fully ingulfed in flames and jumping through the window.??that”ll cure you real quick I guaranty!!
    Of could you will probably be really scared of hospitals for the rest of your somewhat short life.

    I know I’m not the onlyest one out there,can someone give us some help? I know that south Florida is not exactly tarantula city, but,,,damn! There goes another pick up truck!!!

  • Gina Stapley

    We live in Nicaragua, near the coast but also close to an estuary. There are at least 22 tarantula holes/burrow LDS in our front yard alone. There was one in particular that I would see every late afternoon and at night, with her legs extending out of the burrow. I’ve never actually seen this spider outside of the borrow, although there are times when it appears that she’s not in there! It seems recently that she is not inhabiting that burrow anymore, however 2 other burrows have appeared a short distance away. Do tarantulas ever abandon their burrow and move to create a new one! I believe that a lot of these are Zebra tarantulas, although it’s hard to tell! They do have the white stripes on the legs and they are either black or a very dark brown. Again, these are not pets!! But I had become somewhat attached to the one I kept my eye on for the past 7 months or so and now she appears to be gone. Could this tarantula have moved burrows, because maybe the gardener upset the burrow she had been in? Help please bi need advice and can’t seem to find any info about this. Thanks so much.

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