Do dangerous spiders lurk in grocery store produce?

A potentially lethal spider was recently found in a bunch of bananas at a supermarket. What should consumers should do if confronted with one of the leggy critters?















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Non-toxic huntsman spiders (like the one pictured above)are often mistaken for poisonous wandering spiders. Image: ISTOCKPHOTO/DIGITAL69

Last week, a store manager at a Whole Foods in Tulsa, Okla., was surprised—to say the least—to find a large brown spider lurking in a bunch of bananas. The spider was initially identified as a Brazilian wandering spider,  a menacing-looking creature with furry fangs and legs as long as five inches (12.5 centimeters) that is considered to be one of the world's most venomous spiders, and one of the few that can kill humans. (Luckily, an anti-venom to the Brazilian’s bite was developed in 1996.)

According to the Tulsa World, two local entomologists in the end determined that the invader was more likely a huntsman spider, which is large and brownish in color like the Brazilian wandering, but is nontoxic to humans.

Each year, there are several news reports of wandering and huntsman spiders, the main "banana spiders," showing up in grocery store bananas as well as poisonous black widows, which find their way into bunches of grapes on store shelves. Both fruits are generally sprayed with pesticides to prevent insect infestation and usually washed before shipment. Still, even with these precautions and visual inspections, some insects manage to survive.

What draws spiders to bananas and grapes—and what should consumers and produce workers who find the potentially deadly critters in their fruit do?

To find out, we spoke with Linda Rayor, a spider expert and senior research associate  in Cornell University's entomology department.

[An edited transcript of the interview follows.]


How common is it to find a spider in grocery store fruit—and are spiders more common in grapes and bananas from certain regions?
For the bananas, you have a reasonable chance of getting them in ones imported from anywhere in Central or South America, the main sources of the fruit. I have no idea of the actual risk, but there are different types of wandering and huntsman spiders throughout Latin America. You pretty much have a chance of getting black widows—which are found all over the world—in grapes anywhere they grow.

Is there something else about grapes that black widows find especially appealing?
Spiders are going to be found anywhere that there are insects for them to eat—and there are plenty of insects on grapes. They're very common in vineyards around the world. Grape arbors (the supports between grapevines) provide really great support systems for spider webs—they're perfect for cobweb-building spiders like the black widow—and the grapes make great hiding places. (Black widow bites can be toxic to humans, but they’re not nearly as dangerous as those from the most poisonous wandering spiders. They can cause intense pain and shortness of breath, but are rarely lethal in healthy adults.)

How about bananas?

Banana trees have these tightly coiled leaves coming up, and then the banana flowers lean down over that. Well, these banana leaves turn out to be just dandy places for these spiders to live, especially ones that hang out on the leaves. The leaves have this kind of hollow center, so a lot of the spiders hang out in the central, deep-covered hole during the day and then come out at night to hunt on the outside of the leaf. Neither one of them are web-building spiders, and so they just kind of hang out on the leaves at night and nab things that wander or fly by.



18 Comments

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  1. 1. tigerdaveatmu 07:46 PM 3/24/09

    spiders are not insects...check the last line of paragraph 3...

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  2. 2. REDorsey 09:05 PM 3/24/09

    WHO cares???!?!?!?! Spiders are creepy and eeeevil. I step on them ALL - no matter how minute. hairy, ugly little beasties - die die die!

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  3. 3. RavenMom 12:10 AM 3/25/09

    I remember having a discussion with my nephew because he was uncomfortable with me killing every spider in sight - I got the 'they are part of this world and have a right to be here' talk. I made the analogy that if I stumbled into a den of lions, I don't think they'd have a powwow discussing my right to be there since I was a denizen of the planet - I'd be lunch! lol

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  4. 4. Gaz5700 08:13 AM 3/25/09

    The article says "You pretty much have a chance of getting black widowswhich are found all over the worldin grapes anywhere they grow."

    Not quite true. Black Widows are not found in Australia. Also, imported grapes are fumigated which pretty much kills off everything (Aust quarantine laws).

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  5. 5. spleeness 01:49 PM 3/25/09

    This article is fantastic. My first thought was (jokingly) "no more fruit for me!" But really, I will just keep an eye out. So much interesting and useful information in here, thanks!

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  6. 6. Hiccup 09:54 PM 3/25/09

    Spiders are amazing creatures. I have 18 tarantulas, and they are just fascinating.

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  7. 7. rnash 11:25 AM 3/26/09

    The analogy with the den of lions is interesting, but not quite accurate. They wouldn't kill you just because they don't like your looks. Simply catch any errant spider in a jar or cup and put it outside.

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  8. 8. ecstatist 06:05 PM 3/28/09

    You kill (web) spiders, you get (more) mosquitoes (possibly the most human dangerous animal in the world)
    Similarly you kill snakes, you get rats, which as disease and dirt vectors (carriers) and food consumers are way more dangerous than snakes
    Look at the statistics --- be wary of bees
    Especially (and this applies to spiders and snakes) if the possible victim is small (baby, small child), or old and decrepit, or has "bad" allergies.
    Snakes and spiders have terrible "press", (see Genesis, Little Miss Muffet etc)

    If you keep a few webs going in your (bed)rooms, annoying mosquitoes and flies seldom annoy for more than 30 minutes

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  9. 9. pauladriaenssens in reply to REDorsey 03:43 AM 4/1/09

    Very unwise! Suppose they're really aliens. You might start an interstellar war.

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  10. 10. Jim Lacey 11:59 AM 4/1/09

    Our species seems hard wired to be frightened by snakes and spiders. If you observe these creatures, however, snakes are often graceful and spiders fascinating. Beauty, perhaps, is in the eye of the beholder.

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  11. 11. Tempest 01:43 PM 4/1/09

    Think of the recently laid next generation: Let's not forget about the eggs of the spiders hatching in your pantries, and fruit bowls all over the world. I'm sure they are close... creepy extension.

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  12. 12. ecstatist in reply to pauladriaenssens 08:48 AM 4/2/09

    actually its the cats that are alien spies

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  13. 13. ecstatist in reply to Jim Lacey 08:53 AM 4/2/09

    reply to jimlacey

    humans are "hardwired" to fast and/or sudden movements (not specifically to snakes and spiders)

    snakes and spiders were/are a food source

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  14. 14. verdai 08:25 PM 4/17/09

    mah Weavers.
    Don't you dare touch them.

    When will they find a cure for the Honeybee?

    there is no replacement.

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  15. 15. YAra 04:02 PM 6/29/09

    Can these spider's harm or toxic our bananas? How do we know banana's are safe to eat?

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  16. 16. reshma1104 05:25 PM 10/5/09

    what you need to get from store for spider's...

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  17. 17. reshma1104 05:26 PM 10/5/09

    i need help i have no idea about spider's

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  18. 18. Charmaine 07:57 AM 2/9/10

    This article is out of date. I have witnessed 2 people get bitten and die in Seattle and 3 die in Oregon. These Brazilian Wondering spiders are all over North America and killing thousands of people not to mention the livestock and pets. This article is not letting the public know of the real threat. I have seen people die within 3 minutes of a bite in Oregon and Washington. Please be aware of this threat!

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