Mountain lions could disappear by 2050, Hydraulic mining’s destructive power, an ode to Yosemite’s Lyell glacier, Descanso Gardens’ dinosaur era plants, More mosquitos, LAFD drones

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Week of April 12, 2019

Here at the California Science Weekly, we are working hard to bring you the most interesting, informative and entertaining stories about science in the state of California. Every week, we pore through hundreds of articles and Web sites to find the top stories that we believe are worthy of your time. We hope you’ll stay with us and share our work with others via Twitter and Facebook. If there is anything you’d be interested in learning more about, send us a note, and let us know.


An end to California’s magnificent mountain lions?

Credit: US National Park Service

Two mountain lion populations in Southern California face a real threat of extinction if an effort is not made to protect their environment and create so-called “wildlife corridors” through the city’s developed areas, a new study warns.

Thestudy published in the journal Ecologist Applications that examined DNA from the lion’s blood and tissue samples from the 1990s to 2016, shows that the species could soon experience “inbreeding depression”, a term used to describe when genetic diversity has declined to the point that the species’ future existence is called into question. A similar issue occurred with Florida panthers.

The greatest danger facing the magnificent cats remains being struck by a motor vehicle. Mountain lion advocates are hoping for approval for a $60 million Liberty Canyon Wildlife Crossing over Highway 101 connecting the Santa Monica Mountains to the Sierra Madre Mountain Range. It’s possible construction of the corridor could begin as early as 2022.

Yale Environment 360


Hydraulic mining’s efficient destruction

Credit: Eastman Collection of the University of California, Davis

When most of us think of the California gold rush, we picture gold panners hunched over a stream, or shoveling dirt into long, wooden sluices, all in an effort to reveal so-called color, shiny pieces of malleable yellow metal that brought thousands of people to California. But in the later years of the gold rush, in the 1860s and 70s, hydraulic mining was the dominant method of extracting gold from the hills.

Hydraulic mining used high-pressure jets of water to dislodge rocky material or move sediment. The jets were so powerful that men were killed by the force of the water from 200 feet away. It was extremely efficient, but also incredibly damaging to the environment. By the time hydraulic mining was banned in 1884, according to John McPhee’s Assembling California, hydraulic mining was responsible for removing 13 billion cubic yards of the Sierras.

Climate Change

The disappearance of Yosemite’s Lyell glacier

Credit: USGS

Greg Stock is a geologist at Yosemite National Park where, for the last decade, he has documented the decline of the park’s Lyell glacier. The glacier sits on Mount Lyell, the tallest peak in Yosemite National Park (13,120 feet). An 1883 photograph (above) shows the glacier spread across 13 million square feet. Current photographs reveal mostly bedrock now, a sad tale of global warming and the rapid loss of glacial ice in California.

Daniel Duane of California Sunday Magazine visited the remains of the glacier and followed along with Stock as he continued a 135-year effort to map and understand the glacier’s decline. It’s a wonderfully well-wrought tale, but like so many stories in these warming days, it’s a depressing one.

California Sunday Magazine


Descanso Gardens’ rare collection of dinosaur-era plants

Cycad plant

In 2014, La Canada Flintridge residents Katia and Frederick Elsea called the city’s Descanso Gardens with an odd proposal: would the famous horticultural center take their collection of over 180 cycads rare cycads, a fern-like plant from the days of the dinosaurs?

The garden said yes, and now those plants are part of Descanso Gardens’ Ancient Forest. Cycads are so old, in fact, they appear in fossils from over 280 million years ago. That makes them far older than flowers. (Flowering plants first appeared in the Jurassic period about 175 million years ago.) In the Ancient Forest, there are also redwoods, tree ferns and ginkgoes, all “living fossils” from a long past era.

Descanso is also the location of North America’s largest collection of Camellias, a genus found in eastern and southern Asia, from the Himalayas to Japan and Indonesia.  At the gardens, there are also some of the oldest oak trees in the city, dating back to Spanish colonial times, beneath which you can take a stroll or simply hang out and enjoy the shade.

If you’d like to learn more about the gardens, check out this episode of Lost LA.

Descanso Gardens Lost LA


As the planet warms, get ready for more mosquitos

Global warming promises to bring more than just sea level rise, more severe storms, and destructive wildfires. According to researchers at Stanford University, a change in the earth’s temperatures is also likely to increase the range and numbers of biting insects like mosquitos, that seek out warmer, wetter climes. California itself could be impacted, with the insects pushing north from tropical climes.

Mosquitoes transmit numerous harmful diseases including malaria, dengue fever, chikungunya and West Nile virus. It’s estimated that they kill about 1 million people a year.

Stanford University


Los Angeles Fire Department employs drones

Credit: Erik Olsen

The Los Angeles Fire Department (LAFD) has begun a program to use drones to find and respond to fires. It’s potentially a very big deal, given that the 2018 wildfire season was the deadliest and most destructive on record in California. Some 8,527 fires burned across 1,893,913 acres last year. That’s larger than the state of Delaware. It was the largest burned area ever recorded in a fire season, according to the California Department of Forestry and Fire Protection.

The agency is partnering with Chinese drone-maker DJI, in what is being called one of the first partnerships between a drone company and a major fire agency. The LAFD will use drones equipped with both visual and thermal imaging cameras that will provide real-time video and data transmission to incident commanders.

Drone DJ


Building an ancient sailboat…in Irvine

Credit: The Orthogonal project

UC Irvine professor Simon Penny and his students are building an ancient Micronesian outrigger boat called a proa to get people interested in long lost seafaring traditions and to promote indigenous science. He hopes, too, to support Pacific indigenous groups to reconnect with their historic mastery of the sea and sailing. And he’s also doing it because it’s fun. Instead of balsa, the 30-foot boat called Orthogonal will be made out of wood with a fiberglass skin. Penny told the California Science Weekly in an email that the craft could launch as early as summer 2019.


Catland: Disneyland is home to a large colony of feral cats. An Instagram account tells their story in photos.

California Underground: a fascinating podcast from the magnificent new California Magazine Alta takes you into the world of urban explorers, bold adventurers who venture into abandoned buildings and structures.

Pretty Fishes: If you feel like chilling out and having something mesmerizing to look at, put on the live Reef Lagoon Cam at the California Academy of Sciences.

One small thing: The Superbloom…by drone

Credit: Erik Olsen

Sure, you’ve seen all the lovely pictures, but have you seen the Superbloom by drone? Here at the California Science Weekly we decided to visit the Superbloom near Lancaster, but rather than simply take pictures, we busted out our drone to bring you a few images of the rare California Superbloom. Enjoy!

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