It's Raining Anchovies in San Francisco

Anchovies have been falling from the sky onto the streets of San Francisco, with experts theorizing it may be due to an explosion in anchovy populations nearby.

A Reddit user posted that "about 12 eight-inch silver fish just rained down from the sky onto [her] friend's house (roof and back deck)," near Sutro Park in Outer Richmond, Newsweek reports.

Other commenters said that they had seen fish scattered around the city in unexplained places.

One said that they: "saw smaller, about 5-6 inch long, skinny sardine-looking fish scattered in one part of the arboretum," while another said that they "almost got hit by a fish waiting for a bus in Castro."

Also in Outer Richmond, one commenter said they "saw a bunch of fish on the sidewalk, then 1 block down, they started raining down & thumping on the sidewalk."

According to local fishermen, the strange fishy rain is a result of seabirds that are gorging themselves on the anchovies in the bay, which have recently seen a massive population boom.

Increase in Population

The numbers are the second-highest level ever seen, according to a blog post by UC Davis' Otolith Geochemistry & Fish Ecology Laboratory, peaking because of a particularly successful spawning season.

The huge population of anchovies is likely due to a bloom in their prey, plankton, including dinoflagellates and other zooplankton, caused by an untimely upwelling of nutrient dense, colder water in the bay from the deep.

Adam Ratner, associate director of conservation education at the Marine Mammal Center in Sausalito, told SFGate: "The water temperatures right now do appear to be colder than normal, and this has provided some much-needed food for animals such as anchovies, seabirds and marine mammals."

"From Half Moon Bay to Point Reyes, people are telling me they've never seen bait this thick," Larry Collins, president of the San Francisco Community Fishing Association, told SFGate. "I heard stories just last week from guys who said that the water out there was just covered with thousands of birds, and the birds were just sitting on the water with anchovies in their mouths because they can't eat anymore."

As the birds fly over the city, they drop the fish from their overflowing mouths, resulting in the mystery marine downpour.

Fish rain has happened before for other reasons, such as last year in Texarkana, Texas, where fish fell from the sky across the town after getting swept up in a waterspout and being blown large distances by strong winds.

Ratner doesn't know how long this phenomenon will last, as he isn't sure how long the cold water upwelling will continue.

He told SFGate: "We know with climate change that the trend is pointing towards warmer water temperatures becoming the norm, but for the time being, this appears to be providing some additional support for fishing communities, migrating whales and our local sea lions."