February 18, 2013
The Northeast may be prone to blizzards this time of year, but in Brazil it’s raining spiders. In a video that’s covered the Internet like an immense web, a local photographer captures images of thousands of spiders shimmying up and down silk threads attached to telephone pole wires. The footage gives the distinct impression of a shower–or perhaps light snow–of spiders sprinkling down on the shocked residents below.
Erick Reis, a 20-year-old web designer in Santo Antonio da Platina, a town about 250 miles west of Sao Paulo, captured the striking video that has since accumulated more than 2 million YouTube views over the course of the week. “I was shooting an engagement party for some friends of mine and I saw the spiders when I was leaving, now in the late afternoon,” he explained to TV450000, which posted the video. “I’ve never seen anything like it before.”
According to biologist Marta Fischer of the Pontifical Catholic University of Parana, however, the phenomenon is not so strange. ”This type of spider is known to be quite social,” she said. “They are usually in trees during the day and in the late afternoon and early evening construct sort of giant sheets of webs, in order to trap insects.”
Scientists have described around 40,000 species of spiders around the world, but only a handful of them are social. These 23 species are scattered around the world and sometimes swarm, like ants or bees. Females often outnumber males 10 to 1 in colonies that can exceed 50,000 individuals.
Around Sao Paulo and its neighboring cities, she said, it’s not an unusual site to see a sky speckled by spiders. The species, Anelosimus eximius, can be found from Panama to Argentina and lives in colonies sometimes comprised of thousands of individuals. Each spider is around the size of a pencil eraser. As Examiner reports, the species’ webs can stretch from the ground up to tree canopies or human constructions 65 feet high.
If strong winds come along, the web may detach from its anchors, carrying the spiders and their ruined home to new sites where they appear to “rain down.” Catching rides on the wind–en mass–was likely what happened in Santo Antonio da Platina. While the humans gawked below, the flustered spiders were simply trying to pull themselves together after an unexpected journey from some forest or park.
Before North American readers breathe a sigh of relief that this isn’t happening a bit closer to home, however, it’s worth noting that similar colonies live in Texas. In Lake Tawakoni State Park, just east of Dallas, Guatemalan long-jawed spiders construct enormous webs covering up to 600 foot stretches. The spiders build the huge webs in less than two weeks. Researchers think the spiders achieve such sudden engineering feats thanks to their “remarkable reproductive capabilities and ability to disperse by ballooning,” according to A Field Guide of Scorpions and Spiders of Texas.
So far, Dallas residents haven’t reported massive sheets of webs and their arachnid residents “ballooning” into backyards. But, as witnessed by residents of Santo Antonio da Platina, stranger things have happened.
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