Spiders are raining from the sky in rare phenomenon

Autumn is edging closer, which means the return of colder weather, darker nights, pumpkin-spiced lattes – and spiders.

Now, while September and October coincide with the mating season – making spiders more visible in and around the home – parts of San Francisco have been faced with a much larger issue.

Residents across San Francisco, San Jose, Danville and Gilroy have reportedly witnessed an influx of white spider webs floating and sticking to the ground. The webs are filled with baby spiders.

One local told the SF Chroniclethat she saw the webs "all over" and that one even landed in her hand.

"They look almost like the fake spider web stuff that you buy at the Halloween store," she said. "It was very silky and sticky."

"What they are is strands of silk that spiderlings, baby spiders, use to disperse," Fred Larabee, an assistant professor of biology at San Jose State University told the outlet "To get away from where they’re originally born, they spin these silk strands and they get caught by the wind, which pulls the spiders to a new place to live, to new habitats, so they’re not competing with their siblings."

He went on to explain that this is happening because spiders ride individual threads until they land and find their new home.

During this process, the threads can clump with other threads to make a cluster – similar to the reported sightings.

"It’s a great opportunity to learn more about spiders," Larabee said. "It gives the public an opportunity to see some really cool biology that maybe they wouldn’t otherwise."

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