Hundreds of butterflies flew by Brian Brown in a matter of moments as he was standing in his front yard in Monrovia, Calif., on Tuesday. The steady stream of winged insects moved as a swarm. "They were all going in a single direction and moving in a determined manner," Brown said. As the entomology curator at the Natural Museum of History in Los Angeles, Brown knew exactly what he was looking at: painted ladies migrating north. The butterfly species, which migrates from the Mojave Desert to Oregon every spring, is experiencing a population explosion this year, and their fast-moving and massive swarm is expected to reach Northern California any day now. "In 2005, we had a similar outbreak," said Arthur Shapiro, a professor of evolution and ecology at UC Davis. "They arrived here on March 11. I thought it would have been great fun if they arrived here on March 11 again, but they didn't. They should in theory get here this week." When they arrive, Shapiro says some might flutter over to the Bay Area, but he expects the main group to sweep the Central Valley, generally following 1-5 to Oregon. ALSO: Thousands overwhelm California town to see superbloom Painted ladies are reputedly the most widespread butterfly in the world, says Brown, and due to their orange and black coloring, they're commonly mistaken for monarch butterflies. Their population has multiplied this year because thriving plant life and blooming flowers from a wet winter provided a healthy food supply for the butterflies in the desert. "I like to think of them as being like the plagues of locust that used to be around the world, except they eat plants we don't care about," said Brown. "They're looking for what we consider weeds, and as they feed, they build up big populations." The butterflies move quickly, as fast as 25 mph, says Shapiro, and can go for days without stopping. Researchers once tracked a swarm that travel 350 miles from Lone Pine in the Eastern Sierra to Davis, and the butterflies made the journey in three days. This is the largest migration of painted ladies since 2005, and Shapiro says the insects totaled around a billion that year. Shapiro suspects this year's population is similar in size. Social media has been flooded with messages about the butterflies' arrival in Southern California. We share some of those in the gallery above.<doc-sep>Painted lady butterflies pause to feed on the nectar of California’s superbloom near Thousand Palms. David McNew/Getty Images Currently, skies in Southern California look like a scene out of Hitchcock—a little less moody, maybe, and a bit more ethereal. From Burbank to Redondo Beach to South Central Los Angeles and beyond, swarms of butterflies have been flitting throughout the air in a fever dream of irruption and migration. And with the overall numbers of these tiny, two-to-three-inch butterflies, known as painted ladies (Vanessa cardui), appearing to be down in the region (from around 300,000 in 2017 to 25,000 last year, according to one monitoring program), this magical burst of lepidopterans brings both wonder and hope. The painted lady fluorescence is the result of an unusually rainy winter in California—and in the deserts in particular, which also helped spur this spring’s wildflower superbloom. In a statement, James Danoff-Burg, conservation director of the Living Desert Zoo and Gardens, said “the average annual rainfall in the Coachella Valley is three inches. This year, we had three and a half inches on Valentine’s Day alone.” Art Shapiro, an ecologist at University of California, Davis, who’s been studying butterfly migration since 1972, told CNN that “Painted ladies tend to thrive when there’s a superbloom because there are so many plants for the butterflies to lay their eggs on and for caterpillars to eat.” While these butterflies migrate from Mexico every year, through Southern California’s deserts, to the Pacific Northwest, they usually go relatively undetected because there aren’t quite so many of them. This year’s phenomenon is referred to as an irruption. “The difference is that a migration is a seasonal occurrence,” says Matthew Shepherd of the Xerces Society, an invertebrate conservation nonprofit based in Portland, Oregon. “An irruption is a sudden and massive surge in population size that doesn’t happen each year. Essentially, there is a super-abundance of something that leads to a population that is so large that the pressure just keeps pushing the butterflies on the edges further and further is search of flowers.” Another reason the critters are making their way up the coast from Mexico, where they winter in the Sonoran Desert, is because of this crowding. “The pressure of having so many butterflies in one area is forcing them outward,” says Shepherd. “The mass of host plants that the caterpillars eat is as important to this as the availability of nectar to fuel the adults. The butterflies are not so much leaving something behind, but moving in search of plants and areas that aren’t saturated with other painted ladies!” A lovely painted lady in a moment of pause. Renee Grayson/(CC BY 2.0) The small insects flitting through California’s vistas are cousins of the larger and more vibrant monarch, which faced critically low population numbers (down 85 percent) in California last year. Both butterflies are similar in color—orange and black with whispers of white—and are essential pollinators of the state’s plants. Tom Merriman, director of the Encinitas-based butterfly nonprofit Butterfly Farms, says that butterflies “can get into flowers bees can’t get to,” and that “monarchs are considered an indicator species that help us judge the condition of our environment.” According to Merriman, the last time Southern California an event like this was in 2005, an El Niño year. (Then, I-5 was closed in Southern California due to the quantity of dead butterflies on the road surface, Shepherd says.) That wet year, there were estimated to be more than a billion painted ladies. Based on the butterflies that flew through Encinitas just yesterday, Merriman ventures that the region is seeing just as many. “They’re moving pretty quickly and can travel nearly 30 miles per hour and can cover up to 100 miles a day,” Merriman says. Occasionally, the ladies stop to sip nectar from flowers, and then continue their haste. “Think cars traveling on the freeway, they’re all going the same direction but not really together,” Merriman says. “We think it’s going to go on for a few more weeks. They’re not going to be as dense—some will run out of energy and stop to feed and breed, some will run into predators, or worse, automobiles.” The painted ladies are expected to stay, wherever they settle down, throughout the summer. Shepherd’s guess is that they’ll arrive in Oregon sometime in April. They’ll make offspring, and the ones flying north now will almost certainly be grandparents by July. For most of them, the Pacific Northwest will be the end of the road. “Painted ladies mostly die where they are at the end of the season,” Shepherd says, because their average life expectancy is two to four weeks. Then their descendants will travel back to Mexico in the fall.<doc-sep>(CNN) — This year's wildflower super bloom is not only filling California deserts with eye-popping displays of color -- it's also providing a feast for swarms of painted lady butterflies making their way north from Mexico. "This is the biggest outbreak since 2005," said Art Shapiro, a professor at the University of California, Davis, who's been studying the migration of butterflies in the state since 1972. Painted ladies tend to thrive when there's a super bloom, Shapiro said, because there are so many plants for the butterflies to lay their eggs on and for caterpillars to eat. A particularly wet winter has set off a brilliant and vibrant super bloom of bright orange poppies across parts of Southern California. In North America, painted ladies spend the winter around the US-Mexico border and fly north in the spring. Their descendants travel back south in the fall. They are orange and black and are often mistaken for the more famous monarch butterflies. They're typically smaller than monarchs and have a different shape. Shapiro said that last year's migration was the worst he'd seen in his career for both types of butterflies. Related content The monarch butterfly population in California has plummeted 86% in one year Unfortunately, the abundance of painted ladies does not forecast a comeback for monarchs. "It has nothing at all to do with the monarch. It's like asking whether a good year for the economy of Tanzania will be helpful to the economy of Sri Lanka," Shapiro said. "Probably there's no relation." The painted ladies have been spotted flying low and fast through Southern California. "There's no missing them when they go like bats out of hell and they're going in a straight line from southeast to northwest," Shapiro said. "I saw more butterflies in the last 10 minutes than I've seen my entire life," Jason Suppes wrote Tuesday on Twitter. Suppes is an education specialist at an agricultural research facility in Irvine. Shapiro said that at the peak of the migration, the butterflies could fly by at a rate of one per second. He said they tend to fly over obstacles instead of going around them, so they won't get disoriented. Melanie Arias, a Los Angeles history teacher, says the butterflies form a little cloud when they get to a fence at the baseball field at her school. The migration has been a big topic of conversation for her middle and high school students. "It's just a little bit magical," she said. The painted ladies tend to migrate in waves, leaving from different breeding grounds over a couple of weeks.<doc-sep>If you've been on social media this week, you might have noticed Californians going crazy over the sudden appearance of millions of butterflies, flying north en masse through the state. It's pretty much the exact joyful display of nature that the world needs right now. But it's also a beautiful and rare sight in a world where insects are disappearing more rapidly than ever before. Experts are saying there hasn't been this kind of butterfly migration through the state since 2005. So what's going on? 1) Walking the dogs this a.m. I found myself in the midst of the Butterfly migration. My first experience with this phenomenon. I'd imagined it to be a casual, drifting multitude, like a confetti cloud. Not at all. These "Painted Ladies" were headed north with speed & purpose-- pic.twitter.com/J0IazDDjVB — Peter MacNicol (@PeterMacNicol1) March 12, 2019 Contrary to what some people are posting, these aren't monarch butterflies: they're painted lady butterflies. And this is part of their annual migration in the Americas. Every winter, these incredible, brightly coloured butterflies mature in the Californian and Mexican deserts before heading north altogether for the summer - travelling at a breakneck 25 miles per hour (40 kilometres per hour) and barely stopping. Southern California friends: I just sat on the beach in the South Bay for two hours while 1,000s of butterflies flew around and past me. What kind are they? What is happening? #butterflies pic.twitter.com/n1IrEaBy0D — jessica. (@loveheylola) March 11, 2019 The migration is so coordinated that last year, weather forecasters freaked out over an unexplained, city-sized 'blob' appearing on their radars. It turned out to be painted ladies. But while this migration is an annual event, this year is pretty special for California. Experts are saying the state hasn't had this many passing through since 2005, when 1 billion painted ladies flew past on their way north. I've never seen so many Butterflies in my life! They keep coming and are all heading north. It's absolutely stunning! #Butterflymigration pic.twitter.com/aiZQGJyCrS — Matt ?Acevedo (@TheMattAcevedo) March 12, 2019 The reason their numbers have boomed is all the unseasonable rain in the desert so far this year, which triggered a recent flower 'superbloom'. Been seeing a lot about butterfly migration on the tl so I thought I'd share my videos with y'all pic.twitter.com/j92XMOD9bD — Juan Antonio Delgadillo (@jdelgadadd) March 14, 2019 While we still don't know a whole lot about the life cycle of the butterflies, we know they lay their eggs on plants and also feed on those plants after they're born - so the more flowers there are, the more butterflies we get. "When they are scarce nobody notices them," ecologist Art Shapiro from the University of California, Davis, told Deborah Netburn over at the LA Times. "When they are abundant, everyone notices." That's definitely the case this year, with what feels like everyone in California (including Taylor Swift) posting about the butterflies filling the Californian skies. Butterfly migration over Los Angeles. Earth is a spectacular place. pic.twitter.com/CSmWHMTja7 — Ashley N. Manz, APR (@AshleyManz) March 12, 2019 Fun fact: Over in Europe the migration is even more epic, with painted ladies completing the farthest known butterfly migration in the world, flying 7,500 miles or 12,000 kilometres and crossing the Sahara. Unfortunately, we might not see this type of butterfly explosion in future years. While scientists have been concerned about the decline of flying insects for years, a study earlier this year showed just how dire the situation has become. As David Nield reported for ScienceAlert: "A newly published review of 73 reports on insect decline around the world has found that over 40 percent of insect species are threatened with extinction. For some comparison, that rate of local species extinction is eight times faster than we're seeing in vertebrates such as mammals, birds, and reptiles." Scientists still aren't quite sure exactly what is driving these insect deaths, with pesticides, climate change, and habitat loss all implicated. Let's hope this beautiful experience might make more people care about the plight of these incredible insects, and what we can do to protect them while they're still around.<doc-sep>
The front end of a massive migrating butterfly swarm reached Northern California late last week, and the so-called painted ladies are flying through some unexpected places, including San Francisco's Presidio National Park. The butterfly species, which travels from the Mojave Desert to the Pacific Northwest every spring, is experiencing a population explosion this year. As millions filled the skies over Southern California, the winged insects made news headlines and appeared all over social media. The butterflies typically follow an inland route, sweeping the Central Valley. A small number of strays might veer toward the coast, but this year, a larger group migrated west and there are confirmed reports of migrating butterflies along the Great Highway at Ocean Beach, in the Presidio and in Bolinas. Jonathan Young, a wildlife biologist at the Presidio Trust, says there are resident painted ladies in the Presidio who are often spotted feeding on nectar-rich flowers, but the migrating insects are different. They move quickly, up to 25 mph, in a northerly direction, and they usually don't stop. Young hasn't conducted an official butterfly count, but he has seen hundreds in the park and around the Bay Area since Friday. In the eight years since he has worked in the park, he has never seen anything like this. "There has definitely been a big spike in the past couple days," Young said. "It's not the millions they're seeing in Southern California, but it's definitely a migration. I've never heard of the masses come through the city itself." ALSO: California town reopens access to super bloom after closure due to massive crowds Arthur Shapiro, a professor of evolution and ecology at UC Davis, is an expert on painted ladies and he's baffled by their migration this year. "Damned if I know," he said. "It blindsided me. This year, they went to the west for whatever reason. The weather patterns have been very different so that might have impacted it. We had an unusually cold February, and we've only seen some warm weather in the last few days." Shapiro has seen hundreds of migrating painted ladies around the Davis campus, and he thinks there are still hundreds, probably millions, more to come. "The numbers have remained low until yesterday, when I counted over 300 here," Shapiro told SFGATE in an interview Wednesday. "I went out twice. In the morning, I counted one every 90 seconds. That sped up to one per minute in the afternoon. I haven't seen any today due to the bad weather. I expect the flight will not peak until early next week." Shapiro assumes when the main swam arrives, it will pass through Kern and Inyo counties before moving up through the Central Valley. Painted ladies are reputedly the most widespread butterfly in the world, and due to their orange and black coloring, they're commonly mistaken for monarch butterflies. Their population has multiplied this year because thriving plant life and blooming flowers from a wet winter provided a healthy food supply for the butterflies in the desert. This is the largest migration of painted ladies since 2005, and Shapiro says the insects totaled around a billion that year. Scientists suspect this year's migration to be in the millions.