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Maps of Two Cicada Broods, Reunited After 221 Years

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Maps of Two Cicada Broods, Reunited After 221 Years

This spring, two broods of cicadas will emerge in the Midwest and the Southeast, in their first dual appearance since 1803.

A cicada lays eggs in an apple twig.

“Insects: Their Ways and Means of Living,” by Robert E. Snodgrass, 1930, via the Biodiversity Heritage Library

Brood XIII, the Northern Illinois Brood, hatched and burrowed into the ground 17 years ago, in 2007.

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Brood XIX, the Great Southern Brood, hatched in 2011 and has spent 13 years underground, sipping sap from tree roots.

The entomologist Charles L. Marlatt published a detailed map of Brood XIX, the largest of the 13-year cicada broods, in 1907.

Historic map of cicada emergence.

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He also mapped the expected emergence of Brood XIII in 1922.

Historic map of cicada emergence.

This spring the two broods will surface together, and are expected to cover a similar range.

Modern map of cicada emergence.

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Up to a trillion cicadas will rise from the warming ground to molt, sing, mate, lay eggs and die.

A Name and a Number

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Charles L. Marlatt proposed using Roman numerals to identify the regional groups of 13- and 17-year periodical cicadas, beginning with Brood I in 1893.

A brood can include up to three or four cicada species, all emerging at the same time and singing different songs. Long cicada lifespans of 13 or 17 years spent underground have spawned many theories, and may have evolved to reduce the likelihood of different broods surfacing at the same time.

Large broods might sprawl across a dozen or more states, while a small brood might only span a few counties. Brood VII is the smallest, limited to a small part of New York State and at risk of disappearing.

At least two named broods are thought to have vanished: Brood XXI was last seen in 1870, and Brood XI in 1954.

Not Since the Louisiana Purchase

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Brood XIII and Brood XIX will emerge together this year, for the first time in more than two centuries. But only in small patches of Illinois are they likely to come out of the ground in the same place.

In 1786 and 1790, the two broods burrowed into Native lands, divided by the Mississippi River into nominally Spanish territory and the new nation of the United States.

An historic map of the United States from 1783.

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Brood XIII entered the ground in 1786, and Brood XIX in 1790. (Expected 2024 ranges are overlaid on the map.)

An historic map of the United States from 1783.

As the ground was warming in April 1803, France sold the rights to the territory of Louisiana, which it acquired from Spain in 1800, to the United States for $15 million.

An historic map of the United States from 1801.

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That spring, Brood XIII and Brood XIX emerged together into a newly enlarged United States.

An historic map of the United States from 1803.

Their descendants — 13 and 17 generations later — are now poised to return, and will not sing together again until 2245.

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An historic map of the United States from 1868.

A ‘Great Visitation’

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After an emergence of Brood X cicadas in 1919, the naturalist Harry A. Allard wrote:

Although the incessant concerts of the periodical cicadas persisting from morning until night became almost disquieting at times, I felt a positive sadness when I realized that the great visitation was over, and there was silence in the world again, and all were dead that had so recently lived and filled the world with noise and movement.

It was almost a painful silence, and I could not but feel that I had lived to witness one of the great events of existence, comparable to the occurrence of a notable eclipse or the invasion of a great comet.

Then again the event marked a definite period in my life, and I could not but wonder how changed would be my surroundings, my experiences, my attitude toward life, should I live to see them occur again seventeen years later.

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The transformation of a cicada nymph (1), into an adult (10).

“The Periodical Cicada,” by Charles L. Marlatt, 1907, via the Biodiversity Heritage Library

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Video: NASA Announces Artemis III Crew

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Video: NASA Announces Artemis III Crew

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NASA Announces Artemis III Crew

NASA announced the crew of Artemis III mission, which will fly to low-Earth orbit to test rendezvous and docking maneuvers with one or two lunar landers.

“I am excited to welcome you as the next crew in the Artemis journey to successfully return to the moon — this time to stay.” “I’m honored by the role that I’ve been given. I’m also very humbled by the task in front of us. But first and foremost, I’m grateful.” “So with that, the Artemis II crew, comrade, hands you the baton. You got the controls.” “As you know, we had a significant anomaly at our Launch Complex 36A on May 28. We’ve redoubled our efforts and are moving forward.”

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NASA announced the crew of Artemis III mission, which will fly to low-Earth orbit to test rendezvous and docking maneuvers with one or two lunar landers.

By Alisa Shodiyev Kaff

June 9, 2026

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Santa Monica Mountains’ last steelhead trout survived the Palisades fire — and even had babies

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Santa Monica Mountains’ last steelhead trout survived the Palisades fire — and even had babies

Scientists feared the Santa Monica Mountains’ last remaining steelhead trout were dead, smothered by debris flows unleashed by the Palisades fire.

But the endangered fish surprised them: A team of biologists recently spotted 30 of the rare trout — and 21 babies — in Topanga Creek.

“There was a lot of happy dancing in the creek,” said Rosi Dagit, principal conservation biologist for the Resource Conservation District of the Santa Monica Mountains, which works with public and private landowners to conserve natural resources.

That’s because the steelhead here are endangered, at both the state and federal levels. Once, they swam in most streams of the Santa Monicas, but their numbers plummeted amid overfishing and coastal development. Increasingly frequent wildfire has further stressed their habitat. Topanga Creek, a biodiversity hot spot, is home to their last known population in the mountains that stretch from the Hollywood Hills to Point Mugu in Ventura County.

The trout that were spotted, including this one, are part of a distinct Southern California population that’s listed as endangered at the state and federal levels.

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(RCDSMM Stream Team)

The California Department of Fish and Wildlife spearheaded a complex mission to rescue trout threatened by the Palisades fire that sparked in January 2025.

Time was of the essence. The fire hadn’t yet been fully contained. But rain was on the way, which would sweep massive amounts of sediment from the denuded hillsides into the water. Fish are often killed this way.

Crews stunned the fish with electricity, scooped them up in buckets, trucked them to a hatchery and ultimately moved them to Arroyo Hondo Creek in Santa Barbara County.

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Within days, Topanga Creek was choked with mud. Some assumed the fish left behind were goners.

But in March, the conservation district’s team found four. The following month, when water conditions were clearer, they saw more.

“These fish continue to amaze me,” said Kyle Evans, environmental program manager for the state Department of Fish and Wildlife, who had seen the damage to the creek. “I had seen populations get wiped out in similar situations. So when I heard, I was thrilled.”

Evans surmises the fish that survived were in an area of the creek where less charred material and sediment were swept in.

“These fish likely hunkered down, were hiding under some rocks or places to try to get away from the main concentration of flow,” he said. “And luckily they weren’t buried.”

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The ones that were spotted were fairly small, around 6 to 14 inches. Rainbow trout and steelhead trout are the same species, but with different lifestyles. If the fish remain in freshwater, they’ll be considered rainbows. However, they can migrate to the ocean and become steelhead, where they typically grow larger before returning to their natal waters to spawn.

Topanga Creek hasn’t fully recovered from the damage it sustained, but scientists say it’s looking better. Surveys last year were “so depressing,” Dagit said, with very few animals, and stretches that were essentially transformed into flat roads from all the sediment buildup. Some of the riparian canopy burned right down to the creek.

Then came 32 inches of rain over the last nine months, scouring out and moving sediment, creating deeper pools. Dagit said they recently found newt egg masses for the first time in years, as well as a few adult newts and many frogs. Plants that provide cover are starting to recover.

She provided photos comparing certain pools last year and this year, some dramatically transformed. In September 2025, the Shrine Pool could have been an overgrown hiking trail. This April, it was filled with shallow water.

Shrine Pool, Sept. 2025, left, and the same location, April 2026, right.

The Shrine Pool in September 2025, left, and the same location in April 2026, right, with RCDSMM’s Isaac Yelchin donning a wetsuit.

(RCDSMM Stream Team)

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Topanga Creek is home to another endangered fish, the small but hardy northern tidewater goby, often described as cute. Not long before the trout operation, Dagit led a rescue of hundreds of these fish too. Many were repatriated to the lagoon at the mouth of the creek in a moving ceremony last June.

There’s still the matter of what to do with the trout that were moved to Santa Barbara County last year. Evans would like to bring them home to the Santa Monicas at some point, but isn’t sure if it will happen. On one hand, they could bolster the small, genetically isolated surviving population. On the other, they might inadvertently bring in a disease or bacteria. There is some time to decide. Evans estimates the creek still needs to recover for two to three more years.

For now, the fish are functioning fine in their adopted creek. Experts worried the trauma wrought by the move would disrupt their spawning process, but they had babies that spring. This year, they spawned again.

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Pacifica pier cracks, another coastal casualty as seas continue to rise

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Pacifica pier cracks, another coastal casualty as seas continue to rise

The Pacifica Municipal Pier was shut down and taped off Thursday after city workers noticed cracks running through the landmark structure and concrete chunks falling into the ocean.

It’s just one of many coastal California structures that have recently crumbled under pressure from a rising and relentless ocean.

Officials from the small, beach city south of San Francisco said the pier was closed due to “cracking, separation, and displacement of the concrete walkway and structural elements.”

It will stay closed while structural engineers asses its safety.

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Photos taken by city employees show a wide crack that runs from top to bottom and across the structure as well. Other photos show a large horizontal crack under the foundation of a small restaurant on the pier, the Chit Chat Cafe.

The cafe was also shut down.

This is not the first time the 53-year-old pier has shown signs of stress. In 2021, part of it was shut down after handrails along the edge collapsed. And in 2023, after a series of storms pummeled the Central California coast, damaging parts of the pier, the structure was partially closed for more than year.

Those same storms caused extensive damage in Aptos and Capitola, 70 miles south, where piers and waterfront infrastructure were swept away or damaged.

In 2024, a 150- to 180- foot section of the Santa Cruz wharf was ripped off by powerful waves.

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At least 10 of the state’s dozens of coastal public piers were closed for part or all of 2024 due to structural damage sustained in winter storms since 2022. At least five others have longer-term upgrades planned to address structural issues.

“These things are costly to maintain,” said Zach Plopper, senior environmental director at Surfrider. “They are a part of our California coastal culture in many ways, but we’re going to need to reckon with, one, the state that they’re in, and two, the continuous and worsening threats they’re going to experience,”

He said most of the piers were constructed in the early 1900s, and they weren’t built to withstand decades of rough seas, storms and rising sea level.

“With this incoming El Niño, which is forecasted to be significant, and this marine heat wave we’re in the midst of, we’re kind of in uncharted waters as far as what this winter could bring in terms of storms and swells to the California coast, and we’re likely going to see a lot more damage,” he said. “Not just piers, but roads and other coastal infrastructure up and down the state.”

There was no storm in Pacifica earlier this week, so no single event could be blamed for the destruction.

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However, a 2025 report from an outside engineering firm, GHD, found that several sections of the pier were in “poor” or “serious” condition, and they recommended closure before anticipated storms or events that could “subject the piles to high winds, swells and large waves.”

The firm found several areas of the pier where concrete was missing and rebar was exposed and corroding.

“The pier has continued to experience high winds and large waves in a harsh marine environment,” the engineers wrote in the report, noting that continuous exposure to seawater or marine spray was “detrimental” to the structure.

A 2023 city report estimated it would cost $19 million to repair.

That same year, a state law was enacted to require local governments along the California coast to plan for sea level rise in the coming decades.

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Sea level has risen some 8 inches, on average, along the coast in the past 150 years, Plopper said, and researchers anticipate another foot in the next 25 years.

“We’re going to see profound shifts on our coastline, none that we have ever experienced before, and building static structures on the coast just doesn’t work all that well,” he said. “We’re going to have to make some really hard decisions.”

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