Cal Falcons

Skip to content
MENUMENU
  • Cal Falcons
    • History
    • Meet the Scientists
    • Partners
    • Media Coverage
    • Acknowledgements
  • Webcams
  • Falcon FAQ
  • Events
  • Donate
  • Twitter
  • Facebook
  • Instagram
  • TikTok

Cal Falcons

We are the Peregrine Falcons nesting on top of UC Berkeley’s Campanile! Come check out our live webcams to see what we’re up to!

We are ~8 days into incubation. At this stage, the We are ~8 days into incubation. At this stage, the growing chicks have developed a working circulatory system and nervous system. Roughly today, the development of sex organs begins. Lots of things happening inside those eggs as Annie and Lou keep them roasty toasty.

Estimated hatch date is April 11th, so mark your calendars!

#eggs #peregrinefalcon #gobears #developmentalbiology #embryo
We’re getting some awesome meme submissions so f We’re getting some awesome meme submissions so far, but we need Moar! Moar memes!

Submit your falcon memes to: campanileperegrines@gmail.com

Need a source image? Check out our folder here: bit.ly/FalconMemes

#marchmadness #peregrinefalcon #givememore #memes #totallyscientific
Here's the other side of those dramatic photos of Here's the other side of those dramatic photos of Annie defending the nest from yesterday. Amazing to see how quickly Lou jumped off the nest to help Annie defend the territory!

Lou was only gone for a few minutes. The eggs remained safe through the whole encounter. However, this highlights one of the risks of intruders at a nest site - eggs can be left vulnerable when the parents leave to defend the nest.

#dfence #peregrinefalcon #parenting #urbanwildlife
Pretty nasty out there! Luckily, bird feathers are Pretty nasty out there! Luckily, bird feathers are extraordinarily waterproof. Feathers are made of keratin, similar to fingernails. On top of the structural resistance to water, most birds have a special oil gland (called a Uropygial gland) that they use to waterproof their own feathers when they preen. This gland is located slightly above a bird's tail, so you will often see them touching that area with their beak while they're preening.

#peregrinefalcon #atmosphericriver #california #urbanwildlife #undermyumbrella
Egg number four just arrived! Estimated hatch day Egg number four just arrived!

Estimated hatch day is April 11th.

#peregrinefalcon #urbanwildlife #gobears #motherhood #quadruplets
So, we've missed our predicted midnight egg laying So, we've missed our predicted midnight egg laying. We're still at 3. Based on Annie's historic laying interval, the longest she's gone between eggs would put her around 10am today. If we start heading past noon, it'll be relatively unlikely we'll see four eggs this year.

#eggwatch #peregrinefalcon #urbanwildlife #willitbe3or4
An unidentified male taking in the sunset on the t An unidentified male taking in the sunset on the tower this evening. For some unknown reason, Annie and Lou didn't seem to mind his presence too much. While he was sitting on the balcony, Annie and Lou were swapping incubation duties.

Everything seems chill?

#peregrinefalcon #peace #love #pleasedontfight
Tune in tonight around midnight for egg #4. Peregr Tune in tonight around midnight for egg #4. Peregrine Falcons typically lay four eggs, and very rarely five. This clutch size varies by latitude, with fewer eggs laid in the high arctic. In the Bay Area, most nests lay four.

Yes, that's poop on one of the eggs.

#peregrinefalcon #eggwatch #latenighteggs #urbanwildlife #gobears #poop
Egg number 3 is tucked safely under Annie as we sp Egg number 3 is tucked safely under Annie as we speak! Fourth (and likely final) egg is due around 1am on the 11th. Although, Annie has been laying at a slightly faster pace than average this year.

#newmom #eggs #peregrinefalcon #urbanwildlife
Annie inspecting Lou's hard work keeping the eggs Annie inspecting Lou's hard work keeping the eggs dry this morning. Good job, Lou!

#wetfalconcontest #peregrinefalcon #parenting #eggnumber3soonplz #urbanwildlife #cal #gobears #berkeley
Happy egg laying season! We are celebrating the ar Happy egg laying season! We are celebrating the arrival of Annie and Lou's clutch with this year's t-shirt!

This year's shirt is a tribute to Peregrine Falcon parents all over the world. Peregrine Falcons are exceptionally good caregivers. Both parents are highly diligent in their care for their offspring, doing everything from catching food to teaching them to hunt on their own!

https://bit.ly/CFShirt23

As usual, all proceeds go towards stream maintenance, education, outreach, and research!

This year's design by Cal Falcon's own Lynn Schofield.

#calfalcons #eggciting #parentlife #peregrinefalcon #gobears #cal #berkeley #ucberkeley
How can you tell Annie and Lou apart when they're How can you tell Annie and Lou apart when they're on the nest? Well, it can be difficult. We got some shots in identical poses and edited them together. As with almost all Peregrine Falcons, Annie is quite a bit larger than Lou. But that doesn't always help. For coloration, look for a sharp contrast between head/back and orange skin on Lou compared with similar head/back and light yellow skin on Annie.

#familyphoto #peregrinefalcon #urbanwildlife #
Annie and Lou exchanging egg-care duties this morn Annie and Lou exchanging egg-care duties this morning. Lou seems to be taking to his duties very well! He's brought Annie pigeons, cared for the eggs, and been keeping an eye out on the tower for danger.

#dad #eggs #peregrinefalcon #urbanwildlife
🚨🚨🚨πŸ₯šπŸ₯šπŸš¨πŸš¨πŸš¨!!! Second egg al 🚨🚨🚨πŸ₯šπŸ₯šπŸš¨πŸš¨πŸš¨!!!

Second egg alert!

#rightonschedule #peregrinefalcon #whattoeggspectwhenyoureeggspecting
Everyone ready for a deep dive into bird reproduct Everyone ready for a deep dive into bird reproductive systems? Thought so.

A quick synopsis is: eggs are produced sequentially and are laid at a fairly regular rate (in Annie's case, every 2.49 days on average). We expect Annie's next egg to be laid March 6th, at 6:09am-ish.

Ok, so how does this all happen? Well, bird ova (the egg cells) begin development in the ovary. Like in mammals, all the ova a bird ever has are in its ovaries when it hatches. Individual ovum cells start growing through hormonal triggers. This growth creates the yolk of an egg.

Each ovum begins developing a few days apart in Peregrine Falcons, with typically four ova triggered for development in any given year. After an ova matures and grows in the ovary, it is released into the oviduct in a process called "ovulation", where the egg is fertilized.

Female birds can store sperm in their oviducts for weeks at a time, so copulation doesn't need to occur exactly when ovulation does. The egg next enters the longest section of the oviduct, where the "albumen" is added. This is the egg "white".

Next, it receives the inner and outer shell membranes before moving on to the "shell gland". This is where the egg spends the most time as the bird applies a hard layer of calcium to the egg to protect it. The calcium it uses is largely from its own bones.
While in the shell gland, the egg is also pigmented before finally being laid. Once the egg is laid, ovulation of the next egg occurs. It's like an organic conveyer belt of eggs in there!

The whole process takes about 2.5 days in Peregrine Falcons.

Now, I know some of you are looking at that data and saying, "but wait! Annie laid 3 eggs last year! Why do you only have the data for 1 interval?"

Well, that's a bit of a story... You see, birds, like many animals, typically lay a number of eggs equal to what they can care for.

In times of low resources or environmental stress, birds will often lay fewer eggs. And they'll lay more in times of plenty.

What happened last year was that Annie got her eggy conveyer belt going and was well into the development process when Grinnell died.

Rest in comments!

#eggs #science #reproduction #peregrinefalcon
"Hmmmm. What is this round thing? I must protect i "Hmmmm. What is this round thing? I must protect it." - Lou, meeting his first egg.

#peregrinefalcon #firstegg #newdad #urbanwildlife #gobears
🚨🚨🚨πŸ₯š#1!!! 🚨🚨🚨 Annie was quit 🚨🚨🚨πŸ₯š#1!!! 🚨🚨🚨

Annie was quite a bit earlier this year than she ever has been. The earliest previous egg was laid on March 10th!

#peregrinefalcon #firstegg #eggcitement #eggcellent #eggnancy #eggspecting
It's March! That means it's time for 2023's Falcon It's March! That means it's time for 2023's Falcon Meme March Madness!

Submit your falcon memes to: campanileperegrines@gmail.com

And then we'll put together a super scientific bracket or something.

Need a source image? Check out our folder here: bit.ly/FalconMemes

#bracketology #marchmadness #mememadness #memes #peregrinefalcon #birbs
Annie has found her Lou! bit.ly/Annie_Lou Annie has found her Lou!

bit.ly/Annie_Lou
Does he look more like a Lou, an Archie, or a Mars Does he look more like a Lou, an Archie, or a Marshawn? Those are the current top 3 vote getters in our naming contest! Still time to get your vote in!

http://calfalcons.berkeley.edu/vote

#peregrinefalcon #nameme #whosaprettybird #berkeley #gobears
Load More... Follow on Instagram

Cal Falcons

Banner photo by John Davis @jozoqo_photo

Proudly powered by WordPress.