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calfalcons.bsky.social
Cal Falcons
@calfalcons.bsky.social
We are Annie and Lou, the Peregrine Falcons living on the Campanile at UC Berkeley! Check us out at calfalcons.berkeley.edu
To Annie: your patience, care, and tenderness were a beacon of joy and hope in our world.

We miss you.
May 11, 2025 at 8:59 PM
It is estimated that the environment provides approximately $150 trillion of economic benefit every year for free (Jiang et al. 2021). The Peregrine Falcon and Bald Eagle are just two of many stories that demonstrate the power of regulation to preserve the world that we all live in and depend on.
April 25, 2025 at 7:14 PM
In some cases, the damage could be irreversible, as many endangered species could very quickly go extinct without protections.

Environmental regulations protect not only plant and animal species but every person on the planet through clean air and water.
April 25, 2025 at 7:14 PM
The recovery of these species is due almost entirely to legislation that is scheduled to be officially “sunset” by Executive Order dated 9 April 2025 (“Zero-based Regulatory Budgeting to Unleash American Energy). The damage that this could cause could take decades of effort to recover from.
April 25, 2025 at 7:14 PM
the Endangered Species Act (ESA), Migratory Bird Treaty Act (MBTA), and Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), there are currently ~5,000 Peregrine Falcons and ~300,000 Bald Eagles in the lower 48!
April 25, 2025 at 7:14 PM
Read the full study here: bit.ly/AnnieSciencePaper

And press release here: bit.ly/AnnieScienceRelease
March 14, 2025 at 7:30 PM
Not yet. Occasionally we see a bird, but no one regularly
March 13, 2025 at 7:55 PM
Looks like a red-tailed hawk! Nice.
February 26, 2025 at 4:16 PM
Yes, they’re starting to see more and more birds with antibodies. Hopefully immunity will continue to build.
February 25, 2025 at 6:25 PM
Annie may have simply decided she no longer likes the taste of pigeon and wants to spice things up with some sandpipers. We may never know...

We will try to keep you all updated as we learn more!
February 24, 2025 at 6:46 PM
4) Some other dynamic is occurring that we don't understand

Studying wildlife is an exceptionally difficult field. We are afforded only small snapshots into the lives of wild animals. Animals are complex and there could be any number of factors at play in any particular observation.
February 24, 2025 at 6:46 PM
3. Predation. -There are many predators out there, such as Owls or Eagles, that will prey on a Peregrine when the opportunity presents itself. We have seen large raptors in close proximity to the Campanile in the past, and we can't rule out the possibility that they have caused this disappearance.
February 24, 2025 at 6:46 PM
Peregrine Falcons are often highly wedded to the territory location, but they do change spots if the nesting environment is not ideal. This is not a very likely scenario, but is possible.
February 24, 2025 at 6:46 PM
2) Annie and Archie are changing their territory/nesting location due to the effects of HPAI. With substantial numbers of territories empty right now, it's possible that Annie and Archie are exploring options for breeding, maybe even looking for a different mate as pairs lose their partners
February 24, 2025 at 6:46 PM
Other options for what's happening right now are as follows:

1) Annie and Archie are totally fine and just hunting off campus and will return to the nest when they're ready. We've seen Annie disappear from the Campanile before. Perhaps she's just off in a new spot before returning to the Campanile.
February 24, 2025 at 6:46 PM
Have Annie and Archie succumbed to HPAI? We've seen no evidence of a sick/dying bird at the tower, and the last time Annie and Archie were seen, both looked to be healthy. Volunteers have checked for bodies at many of their favorite roosts and have not found anything, but it is still possible
February 24, 2025 at 6:46 PM
Floaters are a sign of a healthy population and ecosystem. The decrease in number of floaters is also an indication that HPAI is affecting not just breeding pairs, but birds looking for their own territories as well. It could take some time for younger birds to fill open territories.
February 24, 2025 at 6:46 PM
Aside from a couple of very brief sightings of a couple of other Peregrines on campus, it has been exceptionally quiet this winter. This is a marked contrast with the population 3-4 years ago, where there were regular intrusions at the Campanile by other falcons (called floaters).
February 24, 2025 at 6:46 PM