Millions of sterile flies are curbing their spread
Jacob Margolis
covers science, with a focus on environmental stories and disasters, as well as investigations and accountability.
Published November 27, 2023 5:00 AM
A Mediterranean fruit fly at the Medfly PRP facility on the Los Alamitos Joint Forces Training Base in Los Alamitos.
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Brian Feinzimer
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LAist
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Topline:
Invasive Mediterranean fruit flies are a major threat to agriculture, and to fight them the state regularly drops millions of sterile male flies all over Southern California. They’re raised, prepped and sent out via a facility near Long Beach.
A long-term problem: The state has been dropping flies en masse for about 30 years, the idea being that the sterile flies will try and mate with fertile, invasive females, limiting reproduction.
A long-term solution: An increased amount of flies will be dropped over a recently quarantined area in and around Leimert Park, at least through June. After that, regular droppings will continue for the foreseeable future.
The small, two-engine Beechcraft King Air is getting jostled by light winds over the L.A. basin. Having taken off from Los Alamitos Army Airfield Base, it’s flying toward one of the 1,750 square miles across Southern California it regularly covers.
A photo of a mediterranean fruit fly against maps of Southern California that line the walls of Mediterranean Fruit Fly Preventive Release Program offices (Medfly PRP) on the Los Alamitos Joint Forces Training Base in Los Alamitos.
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The pilot is guiding the plane while hundreds of thousands of his passengers are crammed inside metal chambers right behind his seat. They're kept in comas by refrigeration, meant to keep them from hurting themselves while in the tight space.
A Medfly PRP representative shows the area of Leimert Park on a map where there is an infestation of non-native fruit flies.
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They’ll wake up only after the pilot opens the trap door, and they start to warm as they fall through the sky, cascading over the city of Los Angeles some 2,000 feet below.
Every week, 3 to 9 million sterile male Mediterranean fruit flies are dropped over Los Angeles, Orange, Riverside and San Bernardino counties as part of the California Medfly Preventative Release Program — a critical tool in stopping the spread of invasive fruit flies, which can threaten the state's agricultural industry.
The inside of a Medfly PRP airplane that releases Mediterranean fruit flies over Southern California.
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Once they land on yards and in fruit trees, they're hardwired to seek out female flies to copulate with. The idea being that if the state drops enough sterile flies, they’ll preoccupy fertile females that get brought in on produce, and stop them from reproducing. The flies can lay their eggs beneath the skins of various crops like pomegranates and figs. When the larvae hatch, they eat the produce, drop to the ground and pupate in the soil, before turning into adult flies. Leaving behind damaged goods.
Just last month, five invasive Mediterranean fruit flies were discovered in the Leimert Park area. Since then, the program has increased its drops over the area to 6 million flies per week, and it will continue with the schedule until at least next June to make sure the problem is solved.
A fruit fly’s trans continental journey
While the program’s home is at the Los Alamitos Joint Forces Training base near Long Beach, a sterile fly’s journey begins in either Hawaii or Guatemala.
“We want to keep our breeding colonies offshore in an area where the fly is already established in the event any flies escape the facility, they don’t start an infestation,” said Ian Walters, director of the medfly preventative release program at Los Alamitos.
A Mediterranean fruit fly at the Medfly PRP facility.
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Adult female flies have their eggs collected from large mating cages, and placed on an edible bedding material, so the larvae have something to munch. Once they’re ready to pupate, they’ll pop themselves out of the trays and into water baths, where they’re once again gathered. This time though, they’re tossed into a giant mixer and covered in pink dye that’ll help scientists identify them with a UV light if they’re caught in traps throughout L.A.
Along the way they’re irradiated with Cesium-137 to make sure that they’re sterile, and then shipped via commercial airlines to California, where about 225 million pupae arrive per week.
Turned on by ginger and dropped from a plane
Once at Los Alamitos, they go into a hot and humid bungalow, where they become adult flies, munching on a mixture of seaweed extract, sugar and water.
Strangely enough, when you walk into check them out in their giant metal towers, the entire room smells like fresh baked gingerbread.
Mediterranean fruit fly incubation crates at the Medfly PRP facility.
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“Ginger root oil has a natural organic compound in it, which increases the mating competitiveness of the sterile males. They also tested orange oil, which has that same compound. But we found that ginger root oil was the most effective,” Walters said.
From there, they get put into refrigerated trucks and are chilled to 38 degrees so that they fall into comas. They're then placed into special hoppers ready to be dropped from an airplane.
An open Mediterranean fruit fly incubation crate at the Medfly PRP facility.
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If they wake up when they’re crammed into the tight space, they could injure themselves, so they sleep until they warm up as they fall through the sky.
The length of an individual fly’s life can vary, but typically lasts around 30 days.
How effective is the program?
There doesn’t seem to be much debate that the program has helped mitigate the number of medfly outbreaks since it began.
“They haven’t had as many outbreaks as prior to that. So in that sense it’s effective in suppressing them,” said James Carey, an entomologist at UC Davis, who’s an expert in invasion biology.
However, there is disagreement about where the invasive flies the state keeps finding in traps are coming from.
Carey argues that it’s likely the medfly has made itself at home here, in part, because they keep showing up in the same relative areas.
But when I asked Jason Leather, the entomologist who oversees the fruit fly program, how likely it is that they’re established, he said, “I think it’s actually zero.”
“Airline passengers are the biggest pathway for fruit flies into California," he added. "During the pandemic, air travel stopped and our traps were really empty."
Again, Carey disagrees.
“The only way you can monitor the wild population is by trapping. Well, guess what? The sterile flies also go to these traps,” Carey said. “It’s not entirely clear if it’s suppressing the populations or suppressing the detection. I would say it’s a little bit of both. But that’s a huge challenge for monitoring.”
A Medfly PRP airplane that releases Mediterranean fruit flies over Southern California prepares to take off from the Los Alamitos Joint Forces Training Base.
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What is certain is that the program will continue for the foreseeable future. And that threats from other exotic pests like the oriental fruit fly need to be dealt with.
If you'd like to help monitor for medflys, you can contact the CDFA and ask if they can put traps in your yard.
RJ Mitte poses for a portrait to promote the film, "Time Share", at the Music Lodge during the Sundance Film Festival, Jan. 20, 2018, in Park City, Utah
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Taylor Jewell
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Associated Press
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Topline:
Actor and disability rights advocate RJ Mitte, who brought a lifetime of experience with cerebral palsy to fictional family struggles in an essential role on “Breaking Bad,” died Monday at age 34, authorities and his representatives said.
Authorities said: Cameron County Justice of the Peace Cyndi Hinojosa told The Associated Press she declared Mitte dead at about 1:30 p.m. at what she believed was his home in Brownsville, Texas. She said she was unable to provide a cause, but an autopsy will be performed.
Actor and disability rights advocate RJ Mitte, who brought a lifetime of experience with cerebral palsy to fictional family struggles in an essential role on “Breaking Bad,” died Monday at age 34, authorities and his representatives said.
Cameron County Justice of the Peace Cyndi Hinojosa told The Associated Press she declared Mitte dead at about 1:30 p.m. at what she believed was his home in Brownsville, Texas. She said she was unable to provide a cause, but an autopsy will be performed.
Mitte played Walter White Jr., the son of Bryan Cranston’s chemistry teacher-turned-meth dealer Walter White on nearly every episode of the five seasons of the AMC show, which recently ranked as the best of the 21st century in a New York Times poll.
Diagnosed at age 3, Mitte told the AP in 2014 that his disability and the surrounding struggles with physical therapy, family problems and exorbitant medical bills — all key subjects on the show — made him better at his job.“You develop a different mentality and you develop a different look at how the world sees you and how you see the world,” he said. “You’re able to use that. And I think it’s an asset instead of something that would hinder.”
Mitte was born and raised in Jackson, Mississippi.
He landed small guest roles on sitcoms after moving to Los Angeles to act in 2006. Like his character, he was in his mid-teens when he began his work on “Breaking Bad,” starting in 2007. The show ran from 2008 to 2013.
“Mitte brought authenticity to the role and built a platform on disability awareness and inclusion,” the actor’s representatives said in a statement announcing his death. The statement said he used “his platform to challenge stereotypes and promote greater representation.”
His later credits included the ABC Family series “Switched at Birth” and the superhero satire series “Guardians of Justice.”
He was also a producer of several independent films.
As an advocate, he served as an ambassador for United Cerebral Palsy and Shriners Children’s. He was also president of his own Mitte Foundation supporting philanthropic and community initiatives around disabilities.
Waves from post-tropical cyclone Rachel crash into beachfront homes in Long Beach, Calif., Monday, Oct. 12, 2026
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Jae C. Hong
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Associated Press
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Topline:
The drumbeat of monster hurricanes in the Pacific has broken a record for nasty long-lasting storms east of the international date line, turbocharged by nature’s supersized El Niño, scientists said. “Since September 20th, when Odalys formed, it’s been berserk,” said Colorado State University researcher Phil Klotzbach, who forecasts and studies storm activity. “This year just everything that forms is just lasting a long time and getting really powerful.”
How it's measured: One of the key measurements meteorologists use to judge hurricane seasons is called accumulated cyclone energy, or ACE, which includes a storm’s wind speed and longevity. On Sunday, a section of the Pacific east of the date line, which brews storms headed for Hawaii, Mexico and the U.S. West Coast, passed the old mark set in 2018. The area is still going strong with Hurricane Simon and appears on the verge of spawning another one that will really ramp up in strength, Klotzbach said.
The backstory: Several meteorological factors have come together to supercharge the Pacific, chief among them the El Niño, Klotzbach and other hurricane researchers said. An El Niño weakens and shifts the high altitude vertical winds that otherwise can dampen or even decapitate storms. In the Pacific, that wind shear runs east to west, generally with the direction storms travel, so it’s like riding a bicycle with a tail wind.
The drumbeat of monster hurricanes in the Pacific has broken a record for nasty long-lasting storms east of the international date line, turbocharged by nature’s supersized El Niño, scientists said.
“Since September 20th, when Odalys formed, it’s been berserk,” said Colorado State University researcher Phil Klotzbach, who forecasts and studies storm activity. “This year just everything that forms is just lasting a long time and getting really powerful.”
One of the key measurements meteorologists use to judge hurricane seasons is called accumulated cyclone energy, or ACE, which includes a storm’s wind speed and longevity. On Sunday, a section of the Pacific east of the date line, which brews storms headed for Hawaii, Mexico and the U.S. West Coast, passed the old mark set in 2018. The area is still going strong with Hurricane Simon and appears on the verge of spawning another one that will really ramp up in strength, Klotzbach said.
On Tuesday, the Pacific will tie a record for most days with a hurricane spinning and is likely to break it soon after that, Klotzbach said.
“It feels like almost everything that can spin up does spin up,” said University of Arizona atmospheric scientist Kim Wood.
El Niño and warm water are boosting Pacific hurricanes
Several meteorological factors have come together to supercharge the Pacific, chief among them the El Niño, Klotzbach and other hurricane researchers said. An El Niño weakens and shifts the high altitude vertical winds that otherwise can dampen or even decapitate storms. In the Pacific, that wind shear runs east to west, generally with the direction storms travel, so it’s like riding a bicycle with a tail wind, Klotzbach said.
Meanwhile, the weather pattern has dampened hurricanes in the Atlantic, where the ACE is less than 18% of what’s normal for this time of year. El Niño makes the wind shear in the Atlantic like riding into a headwind, he said.
Another factor is warm water, which serves as hurricane fuel. By definition El Niño is a warming of the equatorial Pacific that changes weather worldwide. In the Pacific storm basin, it’s several degrees Fahrenheit warmer than normal, said Kristen Corbosiero, a professor of storm atmospheric sciences at the University at Albany in New York.
Usually in the Pacific, the extra warm storm-friendly water doesn’t run as deep as it does in the Atlantic. So when one storm goes over a patch of water, it brings up cold water and makes it hard for a subsequent storm in the same area to stay alive, Wood said. But not this year.
Hurricane Rachel, whose remnants swamped Las Vegas over the weekend, didn’t suffer as it went over, churned up by Category 5 Hurricane Polo, Wood said. She said the waters are warm from both El Niño and climate change from the burning of coal, oil and gas.
Another factor in recent storms was a counterclockwise atmosphere spin over Central America — called a gyre — that spits out seeds of stormy weather that can form into hurricanes. It spit out both the Atlantic’s Isaias and the Pacific’s Simon at about the same time, Corbosiero and Klotzbach said.
Five major hurricanes in a row
The last five Pacific hurricanes — long-lasting Nolo, Odalys, Polo, Rachel and Simon — have all reached major status with winds of at least 111 mph (178.6 kph). Nolo, Odalys and Simon hit Category 4, while Polo set the record for time spent at Category 5 at two-and-a-half days.
When Klotzbach made those calculations on the record-breaking activity of the eastern and central Pacific, he looked at all storms east of the date line.
That’s a slightly different approach from the National Oceanic and Atmospheric Administration, which breaks that broad area into two regions. Neither NOAA-defined region is quite at record levels for ACE yet; put together they are.
Part of that is because often when one of those subregions is more active, the other isn’t quite as crazy, but in 2026 they both are hyperactive, Wood said.≠
“This is the first year that both sides have been this active together,” Wood said. “Usually it’s kind of focused more on one or the other, so that speaks to just the wide extent across this region of where there’s been that lower shear, those warmer waters, and that higher moisture.”
Off the Mexican coast is a disturbance that the National Hurricane Center gives a 90% chance of becoming Tropical Storm Trudy, which then could power up to something big, Klotzbach and Corbosiero said.
“It seems like that area is just one after another. So I would not be surprised to have another storm,” Corbosiero said. “This year, because of the El Niño, we do have very favorable conditions. So as long as there’s some sort of the seeds either from the gyre or from remnant ends of cold fronts, it seems like this is going to continue for a bit.”
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A customer picks produce at the Fairfield Farmers' Market.
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Semantha Norris
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CalMatters
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Topline:
California students enrolled in public colleges and universities are now eligible to apply for CalFresh, the state’s food benefits program, Gov. Gavin Newsom announced Friday.
Who qualifies: Students enrolled in a degree program at a California Community College, California State University or the University of California may be eligible for up to $300 a month to spend on food at grocery stores and farmers markets. Before this change, proving eligibility for Supplemental Nutrition Assistance Program (SNAP) food benefits was a complex process that often discouraged eligible students from applying. With the new changes, undergraduate students who are enrolled at least half time qualify by being enrolled in any degree program at a UC, CSU, or community college. Newsom said that the state expects more than 200,000 additional students to enroll in CalFresh after program expansion.
California students enrolled in public colleges and universities are now eligible to apply for CalFresh, the state’s food benefits program, Gov. Gavin Newsom announced Friday.
Students enrolled in a degree program at a California Community College, California State University or the University of California may be eligible for up to $300 a month to spend on food at grocery stores and farmers markets.
“We can’t expect students to learn if they’re hungry, and in California, there is no reason for them to be, whether they’re in kindergarten, high school, or college,” Newsom said in a Friday statement. “You shouldn’t have to jump through hoops to get the food benefits you’re entitled to, and now you don’t have to.”
Those who are enrolled in an associate or bachelor’s degree program, at least half time, can apply here. Newsom said that the state expects more than 200,000 additional students to enroll in CalFresh after program expansion.
“This is what government is supposed to do: help the people we serve. It is my hope that these changes will continue to make it easier for students to access CalFresh, the largest anti-hunger program in the country,” California Department of Social Services Director Jennifer Troia said in a Friday statement.
EdSource is an independent nonprofit organization that provides analysis on key education issues facing California and the nation. LAist republishes articles from EdSource with permission.
Several homes were red-tagged as waves continue to slam the bulkhead along the Long Beach Peninsula on Monday.
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Topline:
Tropical storm Rachel’s waves and tides battered seaside homes in Long Beach, Newport Beach and Malibu over the weekend, damaging them to the point that some residents had to evacuate. But heavy rains failed to materialize.
Will flooding continue? On Monday morning, the National Weather Service posted their forecast: “Minor to moderate coastal flooding is likely to continue to through at least Tuesday. Periods of light to moderate rain and a low chance of thunderstorms will persist through Monday with below normal temperatures."
What's next: Beginning Tuesday, warm and dry conditions should return through the end of the week.
Tropical Storm Rachel’s waves and tides battered seaside homes in Long Beach, Newport Beach and Malibu over the weekend, damaging them to the point that some residents had to evacuate. But heavy rains failed to materialize, lessening the potentially disastrous impact.
Federal weather officials suggested Monday that while some flooding may remain, the worst of this weekend’s storm is probably over.
“Minor to moderate coastal flooding is likely to continue to through at least Tuesday," said the National Weather Service synopsis posted Monday morning.
“Periods of light to moderate rain and a low chance of thunderstorms will persist through Monday with below normal temperatures,” the synopsis continued.
The weather service said warm, dry conditions should return beginning Tuesday and continue through the end of the week.
Large waves crash over a damaged wooden seawall on the Long Beach Peninsula on Monday.
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Long Beach damage
On Monday, powerful waves continued to batter the Long Beach Peninsula. Eight buildings, which comprise 13 residences, were red-tagged, marking them as unsafe to enter. Mandatory evacuation orders remained in place for buildings along Seaside Walk between 64th Place and 66th Place.
Large stretches of the boardwalk were also destroyed, with pieces of splintered wood littering the water. At 66th Place, residents used sandbags to reinforce the boardwalk and prevent the damage from spreading.
Access to the peninsula remained restricted to local residents only. In areas with wider beaches, crews with heavy equipment worked to build up sand berms.
Crews work to build berms along a stretch of sand in West Newport Beach on Monday.
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Newport Beach had prepared for the storm last week by adding sand to the beach. But spokesperson Georgia Rios said it hadn't been enough.
"Between the elevated high tides, as well as that elevated surf coming in, it breached our berms and went into the roadways," she said.
In West Newport Beach on Monday, sandbags were still piled against doors and garages of many homes, and some streets near the beach were scattered with sand left behind by seawater.
Rios said some homes were flooded, but none had been red-tagged.
On the beach, crews were building sand berms, as they had for days.
“All the work that these crews have been putting in were absolutely essential to keeping flooding out of the homes,” Rob Marienthal, a Newport Beach lifeguard officer, told LAist on Monday.
A couple of days after being inundated by seawater, sandbags continued to surround garages and doorways in West Newport Beach.
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Sand remained in the streets of West Newport Beach on Monday after seawater flooded the area late last week.
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Marienthal added that the berms will remain an important defense against more high tides and swells expected this fall, especially in vulnerable areas like the Balboa Peninsula.
The Newport Beach City Council will be discussing a sand replenishment plan this week.
Rain had less impact than waves
Tropical Storm Rachel's rains were fairly inconsequential. Over the weekend, just over a quarter of an inch of rain (0.29 inches) fell in Long Beach. It barely rained in downtown L.A. (0.07) and Santa Monica (0.02). Just over 2 inches of rain fell at Mount Baldy, according to a National Weather Service post Monday morning.
Meanwhile, at midday on Saturday, winds hit 23 mph at John Wayne Airport in Orange County and 17 mph at the Santa Monica Airport.
Some cities across Southern California declared local emergencies days before this weekend’s winds, tides and waves hit the region.
The city of Malibu declared a local emergency Sept. 28 to prepare residents for rain, mudslides, landslides, debris flows, coastal erosion and flooding that the El Niño weather event could bring.
But officials emphasized that although only some of the potential damage materialized over the weekend, El Niño is far from over.
How we reported this story
LAist correspondent Adolfo Guzman-Lopez reported from Long Beach, speaking to officials from Long Beach and Newport Beach and checking reports from the National Weather Service. Lucas Brady Woods reported from the Long Beach Peninsula and West Newport Beach, interviewing residents and officials and taking photos and videos. Suzanne Levy and Matthew Ballinger edited this report, with additional editing by Jolie Lash.
