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Posted by: atowhee | December 13, 2017

THE WILD PARROTS OF EVERY HILL

San Francisco, December, 2017

Once they were hailed as “The Wild Parrots of Telegraph Hill.”  Judy Irving’s documentary of that name traced their early history in San Francisco.  More than a decade later there are now several parrot flocks scattered across San Francisco.
This species is native to the Andes in southern Ecuador and northern Peru.  The first birds in the flock had been caught in the wild there and imported as they all wore quarantine bands.  They were first noticed in San Francisco in the early 1990s. There may have been only a handful, a small gene pool to begin with. The original birds were all Psittacara erythrogenys, Red-masked conure. In 1995 a single female Mitred Conure, Aratinga mitrat, joined the flock.  She mated for several years and raised hybrid young with her mate.  Their off-spring were also fertile and so those mitred genes were infused into the flock’s genetic diversity. There was at least one long-lived Blue-headed Conure in the flock but there is no evidence that bird ever mated.  Much of what we know of the flock’s early years we owe to Mark Bittner who befriended and studied the birds in their exotic, new home. In the wild the two species do not overlap so this is a new hybrid.
I remember talking with Mark Bittner around 2000.  He explained how many of the first youngsters would sicken and die before they matured.  Now the flock is successfully raising numerous clutches each summer.  The individuals who were susceptible to the endemic pox and fevers of San Francisco birdlife have died off.  The healthy, resistant individuals may now live up to fifteen years or so, often raising a family each summer.  Nature has severely culled the weaknesses from the parrots’ gene pool.
It could be very informative to have information about these flocks and their genetic make-up.  With climate change putting stress on all current ecosystems and species it could be instructive to see how these birds differ from those in Latin America.  What adaptations have they made over three decades in San Francisco?  Recent research in the Galapagos shows that new finch species can evolved there in just a few years.  Are the San Francisco parrots now a new species or sub-species?  How much mitred genetic character persists?  Are there other species represented in the gene pool?
The native population in Latin America is not considered to be of concern.  Could these California birds ever be used to re-populate their ancestors’ former range if the need arises?  We in North America have far more House Sparrows than you can find in Britain.  New Zealand has a healthy population of Goldhammers while they have become scarce back on their native grasslands of Europe
There is no dependable estimate of the parrots’ San Francisco population now. The 2016 Christmas Bird Count had a total of 275, but there is no way to sort out which flocks might have been counted more than once. The skies and parks of San Francisco are often filled with the swirling green flocks and their urgent clarion calls. Recently we spent time with friends who live in the Sunset District.  Their home is at the east end of Quintara where 14th Avenue becomes a narrow alley.  They are just downhill from Golden Gate Heights Park.  Their local parrot flock hangs out near the Muni turnaround and in the trees of the steep slope that drops down toward the Pacific to the west.  The parrots also move in and out of the mature Monterey Cypress that crown the park on the peak.
Researching these birds should not be difficult.  Feathers and feces would be easy to collect.  They are not secretive so any population or breeding studies would require only time and attention.  In some cases private land owners would need to cooperate as well.
How far will they expand?  Will some brave parrots cross the waters? Could they spread to the forests around Mt. Tam?  Will some hopscotch across YBI to Emeryville and beyond? I can imagine their glee at finding the arboretum in Strawberry Canyon.  If they entered the Central Valley what could they possible make of almond groves, vineyards, rice paddies? Their most obvious route is south onto the Peninsula.  I would expect their presence could liven up a number of campuses: Oracle, Intel, Google, Apple, Cisco, Stanford.
Unlike the Collared-Doves that have spread across North America, these parrots remain confined, for now. They have persevered and now thrive in a land where they had not evolved.  They live among plants and other animals their ancestors would never have seen.  Birds from Europe, plants from Australia and South Africa.  All at sea level.  Now that climate change is altering the natural world, we humans must rise to the task of trying to manage on behalf of our fellow species wherever possible.  How these parrots won their place in San Francisco could hold a number of key insights into what other species will have to do as they confront the changes that will surround even the most sedentary plant or animal. Can we humans ameliorate the pending disasters?  The San Francisco parrots may become a model for how humans can help or enable other species to survive the coming extinction crisis.

Rapid evolution of Galapagos finches: https://news.nationalgeographic.com/news/2006/07/060714-evolution_2.html 

I have just published my book, San Francisco’s Natural History: Sand Dunes to Streetcars. It traces the many severe changes man has wrought.  Click here for more info. It is now for sale at Green Apple Books on Clement Street.

 

 

 

 

 

 

 

 

 

 

 

 

Aratinga erythrogenys.or Psittacara erythrogenys, Red-amsked conure or parakeet.

Mitred conure, Aratinga mitrata…in 1995

Parrots FAQ: http://www.markbittner.net/parrot_pages/faq.html#gethere

Pelican Media, producer of parrot and brown pelican docs: https://www.pelicanmedia.org/
1736 Stockton Street, Suite 2
San Francisco, CA 94133    films@pelicanmedia.org   

 

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Responses

  1. We lived in SF for some years and these parrots often visited our Cole Valley neighborhood. Our house was like a perfect blind and so we could study them easily (they’d roost in an apple and oak tree right next to our large 2nd-story picture-window). It was like Jane Goodall, but for parents rather than chimps. We spent much time studying and tracking them.

    There are two main flocks: one roosts in the Presidio and one in the Embarcadero. During the day they disperse into smaller groups and forage. There’s also a flock in Brisbane and a smaller flock in Sunnyvale (silicon valley). Their population seems to be increasing. They didn’t come to Cole valley until 2012.

    Genetically they’re actually hybrids – a mix of Mitred, Cherry-Heads and a couple other species. Cherry-Heads are the dominant thread but if you observe closely there is much variation. Evolutionary pressures are deeply active on these birds. They are much larger and heavier than their tropical kin, and with heavier down. They weigh up to 200g – much heavier than their ancestors. No doubt compensation for the colder weather. They are also affected by a terrible neural disease. This leaves them progressively weaker and eventually they can no longer fly. Many young parrots come down with it. We’ve seen a couple survive this disease but generally it’s fatal. No one knows the origin of the disease – viral or environmental. But it’s another evolutionary stress that heavily prunes back the population.

    We had a young parrot (still entirely green) that would come to our deck every day with her parents. Unfortunately she got this disease and became progressively weaker. She took to roosting in our oak tree in the evening – a desperate act for a parrot as they *always* stick together, particularly at night (a lone parrot is an unhappy parrot). One day she crash-landed on our deck and was too weak to go further. She was almost dead. So we took her in.

    We’ve now had “Belvedere” for 4 years. She recovered from the disease after months of nursing, but will never be able to fly again. However she’s become completely tame and a joy to have around. She now lives in Ashland Oregon with her human flock.

    They’re amazing creatures. Their intelligence and playfulness really shines through. And they’re certainly a case-study in evolutionary biology. Some ambitious PhD student should really consider them for a thesis.


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