Yvonne Duckhorn was shopping at a Milwaukee Aldi with her 4-year-old daughter when she found some red grapes on sale, reports the Milwaukee Journal-Sentinel.  The grapes were packaged in clear containers, which Duckhorn flipped over to check for mold.  When she flipped the container back right side up, she noticed something moving inside the container.  Though she had seen insects on fruit before, she realized this was a rather large spider.  Then, she noticed the distinctive red markings of the black widow spider.  Not wanting to leave the spider for another customer, she bagged the grapes in a large produce bag and alerted an employee.

Duckhorn was not alone in her discovery.  According to Fox News, the black widow spider has been found on grapes in several supermarkets in Michigan, Wisconsin, Missouri, and Minnesota.  While alarming, it is apparently quite common to find live black widows in produce, especially grapes.  The spiders, which are the most venomous spider in North America, move into the grape fields to feast on other bugs during harvest. Food experts say ever since the mid-1990s, food growers have had to cut back on insecticide and there’s little to deter them. Also, their size and shape can make them hard to spot amidst dark red grapes, so the critters get by the inspectors.

National Geographic reports that the black widow spider is a notoriously lethal spider, identified by the colored, hourglass-shaped mark on the abdomen. Several species answer to the name, and they are found in temperate regions around the world.  In humans, bites produce muscle aches, nausea, and a paralysis of the diaphragm that can make breathing difficult.  However, contrary to popular belief, most people who are bitten suffer no serious damage with death being even rarer.  The people most at risk from a black widow bite are those with compromised immune systems.

The majority of recent discoveries of black widow spiders on grapes have been at Aldi stores, though there has been one incident at a Kroger.  Black widows are generally solitary creatures that live for one to three years, making it likely that they could stay on fruit through packaging, distribution, sale, and arrival in a customer’s home.  Aldi said in its statement that it immediately pulled grapes from Milwaukee-area stores in an effort to be as cautious as possible.  The company also said that it was implementing additional inspection procedures at all warehouses and stores.  The company also reiterated its guarantee of a refund to any customer not 100% satisfied with a food product.