
Cal Falcons is a website and social media community featuring three live streaming webcams trained on a peregrine falcon nest site atop Sather Tower at the University of California, Berkeley. Cal Falcons is known for its extensive social media presence and following.[1] The live stream runs continuously throughout the year, recording all facets of the falcon lifecycle, including courtship, breeding, and raising young. The site launched with two cameras in January 2019.[2]
Nest site

Peregrine falcons initially established a territory and nest at Sather Tower in spring of 2017.[3] Initially, the falcon pair laid their eggs on a broken sandbag on the upper balcony of Sather Tower, which was replaced by researchers with a nest box after scientists found that eggs were rolling off the sandbag.[4] In the wild, falcons nest on rocky ledges and cliff faces, so the gravel-filled nest box was designed to mimic those conditions. A permanent wooden nest box was installed in 2018, prior to the pair's second breeding season.[5] Two cameras were installed prior to the 2019 nesting season, allowing continual remote viewing of the nest area.[6]
Breeding pair
The breeding pair that established the territory in 2017 were named Annie and Grinnell as part of a crowdfunding campaign to purchase the cameras.[7] Annie, the female, was named after Annie Montague Alexander, a naturalist who founded the University of California Museum of Paleontology and Museum of Vertebrate Zoology. Grinnell, the male, was named after Joseph Grinnell, the first director of the Museum of Vertebrate Zoology.
On October 31, 2021, Grinnell was injured in a territorial battle with another falcon.[8] He was taken to the Lindsay Wildlife Experience for evaluation and rehabilitation. Grinnell was diagnosed with several injuries, including puncture wounds, a wing injury, and a damaged beak. During the period Grinnell was in the hospital, an unknown male began to court Annie.[9] Grinnell was released from care on November 17, 2021 and subsequently reclaimed the territory from the unknown male.[10] During the 2022 breeding season, Annie disappeared for a week prior to laying eggs, leading to speculation that she had been injured, killed, or driven away from the territory, as multiple unknown female birds were seen courting Grinnell.[11] After her return, Annie laid two eggs with Grinnell. On March 31, 2022, Grinnell was found dead on a road in downtown Berkeley.[12] The cause of death was not known, but he may have been hit by a car after being attacked by a rival falcon.[13] On April 1, 2022, Annie was courted by a new male who quickly established a pair bond with her, leading to a third egg being laid and the entire clutch being incubated by both Annie and the new male. Following a public vote, the new male was named Alden, after Alden Miller, a UC Berkeley ornithologist who succeeded Joseph Grinnell as director of the Museum of Vertebrate Zoology.[14]
In late 2022, Alden disappeared and was replaced by Lou, named after Louise Kellogg, who was the best friend of Annie Alexander.[15] He was nicknamed "Cheeto-feet" because of his bright orange feet. The pair raised a clutch of three chicks in the 2023 breeding season,[16] and both Annie and Lou could be seen on the campus in the months following the chicks' fledging in July.[17]
In early 2024, Lou disappeared, and a few weeks later was replaced by Archie,[18] named after UC Berkeley alumnus Archie Williams, winner of the Olympic Gold in the 400 meter run in the 1936 Olympics and later becoming an Air Force Colonel.[19] The pair raised a clutch of four chicks together in the 2024 breeding season.[20]
Nesting history

Between 2017 and 2021, Annie and Grinnell raised a total of thirteen chicks,[21] twelve of which successfully fledged. One, named Lux, died shortly after leaving the nest site by hitting a window.[22] Prior to Grinnell's death in 2022, Annie also laid two more eggs, assumed to be fathered by Grinnell. As of April 2022, Annie had also laid an additional egg of unknown parentage. The chicks, eventually named Grinnell Jr. and Lindsay, grew up, but two months after fledging, Lindsay got killed by red-shouldered hawks.


Between 2023 and 2024, Annie raised a total of seven more chicks with her new mates: three with Lou and four with Archie. All seven chicks fledged, but Equinox - nicknamed "Nox" by fans - was found on July 5, 2024 in the Berkeley Marina with a broken wing.[23] He was brought to the UC Davis Veterinary Hospital to be treated and was released on October 19. He was found again three days later in Richmond, showing signs of being severely anemic and emaciated, and succumbed to pneumonia on October 23.[24]
Each year, Cal Falcons held a naming contest for the season's chicks largely via social media.[25] Previous names have included Berkeley's motto (Fiat/Lux), chemical elements discovered at UC Berkeley, conservationists critical to the peregrine falcon's recovery, California state plants, falcon figures in Native American tradition, famous scientists, and Grinnell-related topics.[26] The 2023 and 2024 chicks both had names suggested by and voted on by the public through social media. Two of the chicks' names in 2023 were suggested by children through a partnership with the Berkeley Public Library,[27] and the chicks in 2024 were named with an Earth Day and celestial event theme in mind.[28]


Two of the chicks fledged from UC Berkeley, a female named Lawrencium (aka Larry) and a male named Sequoia, are known to have established territories in the San Francisco Bay Area.[29] However, after Sequoia's mate succumbed to avian flu, he disappeared.[30] Lawrencium has successfully raised several broods of chicks on Alcatraz Island.[31] They had three chicks in 2023, and four chicks in 2024.[32]
Disappearance
Towards the beginning of January 2025, Annie and Archie disappeared, with fans voicing concerns over the spread of avian flu.[33] This hypothesis was supported by the Cal Falcons themselves in a social media post after the pair had not been seen on campus for about two months.[34] This followed reports of declining numbers of Peregrine Falcons in the United States since the outbreak of the strain in 2022.[35][36] Even with no falcons currently residing at the top of Sather Tower, the webcams that were installed are still being maintained and utilized.
References
- ^ Newitz, Annalee (30 March 2022). "Reality TV for birds shows that conservation research can pay off". New Scientist. Retrieved 8 April 2022.
- ^ Brice, Anne (5 February 2019). "Peregrine falcon cameras installed on the Campanile". Berkeley News. University of California, Berkeley. Retrieved 8 April 2022.
- ^ Brice, Anne (8 June 2017). "Peregrine falcons nest on UC Berkeley's Campanile". San Francisco Chronicle. Berkeleyside. Retrieved 8 April 2022.
- ^ Brice, Anne (8 June 2017). "Peregrine falcons nest on UC Berkeley's Campanile". San Francisco Chronicle. Berkeleyside. Retrieved 8 April 2022.
- ^ Brice, Anne (31 January 2018). "Campanile peregrine falcons coupling up again, with a new nest box". Berkeley News. University of California, Berkeley. Retrieved 8 April 2022.
- ^ "New Webcams to Watch Baby Falcons Being Raised at UC Berkeley's Campanile". NBC Bay Area. 13 March 2019. Retrieved 8 April 2022.
- ^ Brice, Anne (16 October 2018). "Campus launches crowdfunding effort to install falcon cams on the Campanile". Berkeley News. University of California, Berkeley. Retrieved 8 April 2022.
- ^ Morris, Joan (3 November 2021). "UC Berkeley's beloved peregrine falcon injured in turf war". The Mercury New. Retrieved 8 April 2022.
- ^ Solis, Nathan (4 November 2021). "Berkeley has a birds eye view of peregrine falcons' love triangle". LA Times. Retrieved 8 April 2022.
- ^ Morris, Joan (4 January 2021). "Annie and Grinnell share a falcon mating ritual for the first time since Grinnell was injured". The Mercury New. Retrieved 8 April 2022.
- ^ Kell, Gretchen (28 February 2022). "Where's Annie? Berkeley's beloved peregrine falcon is missing". Berkeleyside. Retrieved 8 April 2022.
- ^ "Cherished falcon at University of California, Berkeley dies". AP News. 31 March 2022. Retrieved 8 April 2022.
- ^ Kell, Gretchen (31 March 2022). "Beloved falcon Grinnell found dead". Berkeley News. Retrieved 8 April 2022.
- ^ Flores, Jessica (18 April 2022). "The 'new guy' in UC Berkeley's falcon soap opera has been given a name". San Francisco Chronicle. Retrieved 4 May 2022.
- ^ "Naming of UC Berkeley's newest falcon mate echoes historical Cal love story". East Bay Times. 2023-03-02. Retrieved 2023-07-15.
- ^ Kell, Gretchen (13 April 2023). "Berkeley's falcon family of five: Annie, Lou and three fluffy chicks". Berkeley News. Retrieved 28 October 2025.
- ^ Kell, Gretchen (12 July 2023). "Empty nest: Annie and Lou's young falcons have flown away". Berkeley News. Retrieved 28 October 2025.
- ^ Kell, Gretchen (31 January 2024). "Nesting season is here, with a new mate for Annie, UC Berkeley's longtime peregrine falcon". Berkeley News. Retrieved 28 October 2025.
- ^ Kell, Gretchen (19 February 2024). "It's Archie! Contest ends to name UC Berkeley's new male peregrine falcon". Berkeley News. Retrieved 28 October 2025.
- ^ Kell, Gretchen (24 April 2024). "UC Berkeley's Annie the falcon sets a record: All of her eggs hatch on the Campanile". Berkeley News. Retrieved 28 October 2025.
- ^ Rae, Alexandra (2 March 2022). "UC Berkeley's Famous Peregrine Falcon, Annie, Just Faked Her Own Death". KQED. Retrieved 8 April 2022.
- ^ Brice, Anne (12 July 2017). "Baby peregrine falcon Lux hits window on campus, dies". Berkeley News. Retrieved 8 April 2022.
- ^ Kell, Gretchen (25 July 2024). "Hard knocks for Nox, UC Berkeley's youngest peregrine falcon". Berkeley News. Retrieved 28 October 2025.
- ^ Kell, Gretchen (5 December 2024). "Nox the falcon died of pneumonia, says UC Davis veterinary pathology report". Berkeley News. Retrieved 28 October 2025.
- ^ "One of the Falcon Chicks Hatched at UC Berkeley Has Been Named After Dr. Fauci". SFist. 21 May 2021. Archived from the original on 1 March 2022. Retrieved 8 April 2022.
- ^ "Cal Falcons FAQ". Cal Falcons. Retrieved 8 April 2022.
- ^ Kell, Gretchen (12 May 2023). "Meet Zephyr, Luna and Rosa: UC Berkeley's new falcon chicks get named". Berkeley News. Retrieved 28 October 2025.
- ^ Kell, Gretchen (23 May 2024). "Meet the falcons: Aurora, Eclipse, Nox and Sol". Berkeley News. Retrieved 28 October 2025.
- ^ Seher, Tori. "Peregrine Falcons May Be Nesting on Alcatraz". National Park Service. National Park Service. Retrieved 8 April 2022.
- ^ Golden, Kate (2023-04-13). "Avian Flu Claims Condors and A Beloved Falcon". Bay Nature. Retrieved 2023-07-15.
- ^ Barmann, Jay (31 July 2020). "Better Falcon News: Nesting Pair Has Two Chicks on Alcatraz, Famed Berkeley Pair Has Three Fledglings Out of the Nest". SFist. Archived from the original on 25 July 2021. Retrieved 8 April 2022.
- ^ McMenamin, Dan (5 May 2024). "'This all started as a what if': Public can now watch Alcatraz Island falcons on new webcam". Local News Matters. Retrieved 28 October 2025.
- ^ Barmann, Jay (25 February 2025). "Berkeley Falcon Watchers Voice Avian Flu Fears After Falcon Annie and Mate Go Missing". SFist. Retrieved 28 October 2025.
- ^ Kell, Gretchen (24 February 2025). "UC Berkeley falcons Annie and Archie are missing. Is avian flu the cause?". Berkeley News. Retrieved 28 October 2025.
- ^ Gallagher, Tim (17 September 2024). "Why Are Peregrine Falcon Numbers Falling in the United States Again? | Audubon". www.audubon.org. Retrieved 28 October 2025.
- ^ Hunter, Chase (28 February 2025). "Berkeley's two famous peregrine falcons aren't the only ones disappearing from Northern California". The Mercury News. Retrieved 28 October 2025.
External links
- Website