Californias native western gray squirrel, Sciurus griseus | Photo: California Department of Fish and Wildlife, some rights reserved
Heres another story in our series on citizen science in California, our way of celebrating Citizen Science Day on April 16.
As a young child, I spent many nights sleeping at my grandparents house in the flats of Northridge, not far from the CSUN campus. Upon waking Id tiptoe down the hallway, carefully so as not to let the floorboards creak under my weight, and climb onto their bed, a perch from which I could survey the early morning goings-on in the backyard. Thanks to all the fruit trees my grandfather had planted over the years, it was a haven for local wildlife.
I watched crows hop across the grass, hummingbirds zip among the flowers, and squirrels chase each other along the fences and power lines. If you grew up, as I did, in the San Fernando Valley, you could be forgiven for thinking of the valleys resident squirrels as locals.
It was not until many years later that Id come to learn the truth: those cute, wide-eyed squirrels that Id spent so many hours watching from my grandparents bedroom? They were trespassers from a distant land, invaders who had driven out the locals nearly a century before - and now the subject of a citizen science project to track their presence.
--
--
The squirrels conquest began several miles to the south, through the Sepulveda Pass. In 1904, the Veterans Administration hospital in West LA was called the Sawtelle Veterans Home, and it served vets from both the Civil and Spanish-American Wars. The Civil War vets were often from the American South, places like Kentucky or Tennessee. Some of those vets brought their pet squirrels along with them. (Like our modern backyard chickens, these animals were pets right up until they wound up in a stewpot.)
Introduced fox squirrel plots its next move | Photo: Ingrid Taylar, some rights reserved
Here is where verifiable fact gives way to folklore: it is said the vets would feed their furry friends with table scraps. Administrators at the V.A. found this an unsuitable use of government-funded resources. Faced with the prospect of letting their companions starve, the vets took a slightly more welfare-oriented approach. They turned the squirrels loose, right there on the V.A. grounds, Jim Dines, curator of mammals at the Natural History Museum, said several years ago when first recounting the tale for me.
For a time, the squirrels remained in the vicinity of the V.A., but thanks to the ever-increasing erection of telephone wires and above-ground cable, the squirrels learned they could use them to avoid getting hit by cars or nabbed by domestic cats. County records reveal that by the 1930s, the invaders - eastern fox squirrels, Sciurus niger - had discovered an agricultural bounty waiting for them in the valley, to the detriment of local farmers. Los Angeles at the time was far less developed than it is now, much of the valley having been occupied by orchards of citrus and walnut.
Thats probably not the only time that eastern fox squirrels were introduced to the Southland, but as a result of their can-do spirit and general adaptability, they rapidly came to dominate the region.
Our native western grey squirrel, Sciurus griseus, is something of an ecological diva. Whereas the eastern fox squirrel is content to feast on anything and everything (a camera trap deployed by Natural History Museum researchers once caught a squirrel chowing down on a pizza crust), its western grey relative is far pickier. It requires native oak trees to survive, depending on its acorns and on the fungi that grow among its roots for sustenance, along with the leaves and fruits of a few other native trees that commonly grow alongside oaks.
Western gray squirrel in its natural environment | Photo: David A. Hofmann, some rights reserved
While our urban development pushed these habitat specialists into the few remaining native oak forests in the San Gabriel, Santa Monica, Santa Susana, and Verdugo Mountains, there they remain at risk of displacement by their eastern counterparts. Because while the fox squirrels are happy living in the suburbs, theyre equally happy establishing a homestead in undeveloped areas.
Some years ago, before Julie King became the Catalina Island Conservancys Director of Conservation & Wildlife Management, she studied squirrels. In particular, she was interested in understanding the squirrels inter-species dynamics in places where their ranges overlapped: did they get along, did they fight? And if so - who won?
Thanks to simple photos matched with timestamps and geotagging data, researchers can understand what allows the two species to coexist peacefully and where to focus efforts to protect western greys.
She was surprised to find that in antagonistic interactions, it was usually the grey squirrels that started the fights, and it was usually the greys that triumphed. Instead, the fox squirrels overall domination might have to do with their fecundity. They deliver litters twice each year, while grey squirrels reproduce just once each year. The natives are simply outnumbered by their competition. In spots with sufficient resources for both species to coexist, they seem to get along just fine, but in smaller habitats, the fox squirrels quickly prevail. In one spot in Pomona several years ago, the wholesale replacement of grey squirrels by fox squirrels took just three years.
A 2013 survey conducted on behalf of the LA Zoo found that western greys persist west of the 405 and east of the Cahuenga Pass, plus one possibly genetically isolated population within Griffith Park. In between the 405 and the 101, [in] Beverly Hills, Bel Air, Franklin Canyon, Stone Canyon theyre just gone, said mammal researcher Miguel Orde ana, who is also citizen science coordinator at the Natural History Mu
Most recent headlines
09/11/2025
Dalet today announced a transformative leap forward for media operations: Agentic Artificial Intelligence (AI) that unifies the Dalet ecosystem under one natura...
22/10/2025
Prime Video Inks Deal To Present NFL Black Friday Game Worldwide By SVG Staff
Wednesday, October 22, 2025 - 10:06 am
Print This Story | Subscribe
Story ...
22/10/2025
NBA Tip-Off: ESPN Goes 1080p HDR End-to-End, Flipping HDR Switch on REMI and REM...
22/10/2025
FloSports Empowers Division II, III Athletic Departments With Turnkey Production...
22/10/2025
Wall Street Video Summit Debuts, Bringing Together 200 Financial Enterprise Vide...
22/10/2025
Dueling Pianos: International Chopin Piano Competition Is as Competitive as a Ba...
22/10/2025
In 1995, a young Colombian artist released an album that would change Latin pop ...
22/10/2025
Over the past few months, a photovoltaic system has been installed on a three-he...
22/10/2025
The Orion spacecraft for NASA's Artemis II mission is stacked on the Space Launch System (SLS) rocket in High Bay 3 of the Vehicle Assembly Building at Kenn...
22/10/2025
L3Harris' Hybrid SATCOM is resilient by design, offering path diversity that eliminates vulnerabilities by routing data across the best available networks i...
22/10/2025
WASHINGTON, D.C. Organizers of NAB Show New York said they are expecting more than 12,000 registered attendees from about 100 countries along with 260 exhibitor...
22/10/2025
WASHINGTON, D.C The organizers of The 2025 NAB Show New York have announced that they are expecting more than 12,000 registered attendees from about 100 countr...
22/10/2025
Masque Sound, a leading theatrical sound reinforcement, installation and design company, supplied an extensive gear package of professional-grade equipment for ...
22/10/2025
Lightware, a global leader in signal management and AV connectivity solutions, is seeing strong market momentum for the UCX-3x3-TPX-RX20, a compact transmitter-...
22/10/2025
MELVILLE, N.Y. Chyron has released PAINT 10.2, the latest update for its telestration platform, adding support for SMPTE ST 2110 IP workflows, expanding brandin...
22/10/2025
WASHINGTON Run3TV today said NBCUniversal is joining as an investor in the ATSC 3.0 Framework Authority, which develops the Run3TV NextGen TV application platfo...
22/10/2025
ATLANTA swXtch.io will feature two new networking solutions extending the company's reach across more cloud and on-prem workflows at NAB Show New York, set ...
22/10/2025
The Warner Bros. Discoverys HBO Max streaming services has increased prices for all its streaming tiers effectively immediately for new customers. Existing cust...
22/10/2025
LOS ANGELES OpenDrives has signed a new distribution partnership deal with Versatile Distribution Services (VDS) to strengthen its channel and streamline how it...
22/10/2025
WASHINGTON, D.C The organizers of The 2025 NAB Show New York have announced that they are expecting more than 12,000 registered attendees from about 100 countr...
22/10/2025
Samora Pinderhughes Brings Immersive Sound to Berklee's Signature Series The artist and composer, who's worked with Herbie Hancock, Robert Glasper, Co...
22/10/2025
BMI Day at Berklee Celebrates Composer Fil Eisler and Awards Scholarship to Stud...
22/10/2025
Rohde & Schwarz and TRUMPF cooperate in drone defense Rohde & Schwarz and TRUMPF partner to deliver a comprehensive drone defense solution combining Rohde & S...
22/10/2025
European Broadcaster Upgrades To Grass Valley's NativeIP LDX 135 Cameras And...
22/10/2025
Everyone Gets a Better Deal on Verizon with New FOX One Perk The $15 FOX One streaming service perk is yet another way Verizon continues to add savings for cu...
22/10/2025
First Look Hidden Assets Series 3
Premieres on 9th November 9:30pm on RT One & RT Player
WATCH HERE Promo Link: Hidden Assets Series 3 | RT
The Crimin...
21/10/2025
NAB New York 2025: Although AES Show Is on Its Own, Audio Will Be a Major Part o...
21/10/2025
NAB New York 2025: Business of Broadcast and Media,' Future of Content'...
21/10/2025
SVG All-Stars: Ethan Folz, Senior Director, Digital Operations and Quality of Ex...
21/10/2025
NBA on NBC/Peacock: Livestream Offers Graphic Overlays, Predictive Gaming, Ancil...
21/10/2025
NBA on NBC/Peacock: At the Front Bench With Producer Frank DiGraci and Director ...
21/10/2025
NBA on NBC/Peacock: NBC Sports, NEP Build Ultra-Flexible Production Plan That Se...
21/10/2025
Indigenous storytelling has been at the heart of the work of the Sundance Instit...
21/10/2025
Top L-R: Mysterious Skin, American Dream Second Row L-R: Little Miss Sunshine, D...
21/10/2025
Last week, Spotify and Columbia Records transformed Pier 4 at the Brooklyn Army ...
21/10/2025
SBS Learn's Dharug Ngurra resource empowers classrooms to meaningfully celeb...
21/10/2025
As global operators simplify and evolve their digital platforms, NPS improvement...
21/10/2025
Critical Design Review completion is a key milestone on the path toward Wideband Global Satellite Communications certification for the network in 2026, opening ...
21/10/2025
New Australian undersea training range to implement and improve warfighting tactics, proficiency and safety; enable joint/allied training that contributes to pr...
21/10/2025
eds3_5_jq(document).ready(function($) { $(#eds_sliderM519).chameleonSlider_2_1({...
21/10/2025
September, the beginning of autumn, brought an expected revival to the TV market, largely due to the new fall TV schedules. The time spent in front of the TV sc...
21/10/2025
Broadcast Booms with 20% Uptick vs. August, Achieving Largest Monthly
Increase ...
21/10/2025
During September, streaming's share of TV viewing in Mexico settled at 24.5%, a marginal shift of -0.5 share points from the previous month.
Disclaimer: YU...
21/10/2025
RENNES, France BBright and GlobalM have conducted a technical trial validating Ultra HD interoperability across the entire contribution chain in the cloud, achi...
21/10/2025
Kokusai Denki Electric America will mark the U.S. debut of a new 4K camera at the 2025 NAB New York, Oct. 22-23. Now available, the Z-HD6500-S1 UHD/HD productio...
21/10/2025
Triveni Digital, a trusted leader in ATSC 1.0 and 3.0 service delivery, data broadcasting, and quality assurance solutions, will showcase its entire NEXTGEN TV ...
21/10/2025
Radio Azzurra FM, longest-running radio station in the province of Novara, northwest Italy, has invested in an DHD SX2 audio routing and mixing console for inte...
21/10/2025
Globecast, the leading provider of broadcast, media and entertainment managed services, has announced the appointment of G Morgan as Executive Vice President of...
21/10/2025
Visual Data announces the appointment of Maz Al-Jumaili as Senior Vice President, Worldwide Localization, to advance client engagement, strategic partnerships, ...
Californias native western gray squirrel, Sciurus griseus | Photo: California Department of Fish and Wildlife, some rights reserved 
