Spider webs have appeared to be floating across Bay Area skies, and there's a logical explanation for the phenomenon.
NBC Bay Area recently received reports and several viewer videos showing white, sticky clumps of webbing floating in the air from Dublin to Gilroy and even as far south as Monterey.
Morgan Hill resident Marisa Flynn told NBC Bay Area Thursday that she has seen them while playing pickleball.
“We thought it was some kind of Halloween stuff floating around. They were almost like a cotton ball material. Big, clumpy and white,” she said.
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The white clumps are exactly what they appear to be: spider webs. They are part of a process called "spider ballooning.”
After many baby spiders are born, they release tiny strands of silk that act as parachutes, letting them catch the breeze and float away to find their own homes.
“Spiders, after they hatch, they disperse. A lot of animals disperse. They get away from where they were originally born because when you hatch, with hundreds or thousands of siblings, there’s a lot of competition for food,” said Dr. Fred Larabee, an assistant professor of biological sciences at San Jose State University.
Larabee added that he’s not sure what kinds of spiders are doing this right now. He says it’s common in the fall and spring for most species.
“But they’ll be individual strands sort of floating around by themselves. But then, once they touch each other, they are kind of sticky so they stick together,” he said.
So why are so many people noticing them now? Larabee says it’s because the number of arachnids vary from year to year, and this year may be a bumper crop.
“It does happen every year, but if populations are really big, you’re going to notice it more because there’s more of them around,” he said.
San Martin resident David Marshall said Thursday he's familiar with spider ballooning.
"A lot more than I’ve seen in the past," he said. "You don’t see them every year. At least I haven’t. In Gilroy yesterday, there were a lot of them."
Many people agreed Thursday that nature picked the perfect time, right before Halloween, to offer up this mysterious science lesson.
