May Recap
In case you missed it you can find last month's newsletter here: may newsletter
May bird walk
In May we birded at Mount Davidson for the first time.
The highlight was a great horned owl and two owlets!
May took the following photos:
Thank you to everyone who came out and thank you to May for the photos :)
June Bird Walk
This month we'll head back to Golden Gate Park, but this time we'll check out Blue Heron Lake.
We're now in summer and it may not be as exciting as the migration seasons that precede and follow,
but we will keep an eye out for some interesting breeding behaviors from the birds we see!
The birding walk will be on the saturday morning of june 20th.
Head to the partiful link
to rsvp.
Spotlight Bird: Great Horned Owl (Bubo virginianus)
The owls are the talk o the town right now and with our Mt Davidson sighting they make an apt bird of the month.
Fun Great Horned Owl Facts:
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Those "horns" or "ears" are called plumicorns.
They have nothing to do with hearing they are just tufts of feathers.
The etymology is Latin for pluma (“feather”) + cornu (“horn”).
They 'why' is apparently a bit complex. A paper from 1981 examined some of the hypotheses and found the 'camoflauge' theory to be compelling as one of the primary reasons. Basically they are nocturnal and the plumicorns looks sort of like broken branches and help them blend in a bit more in the day during their periods of inactivity. A more recent study using evolutionary history seemed to come to similar conclusions. But there are other theories too covering reasons like intimidation, species recognition, and communication. -
They are found in sf year round.
In particular, they garner interest in the city around spring to summertime when the owlets pop up.
They are particularly popular in Bernal Heights Park as well as in the Presidio, GGP, and as we saw, Mt. Davidson.
ebird weekly bar chart for sf - Like other owls they are incredible hunters. They hunt at night and are pretty much silent due to their fringed feathers, and with their size they can take down pretty large or formidable prey. I won't share anything here because it can get pretty brutal, but I've seen videos of them hunting a pretty wide variety of animals including skunks, ospreys, you name it.
- Speaking of hunting and diet, if you're like me you dissected owl pellets in science class growing up and saw all the little bones that the owls ate. But according to one study of great horned owls I stumbled upon, they found feathers of birds in the pellets but only the bones from mammals indicating there may be some bias in certain owl studies if they only look at bones to identify owl diet.
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Depending on who you ask there are something like 10-20 subspecies of Bubo virginianus.
Subspecies science is a pretty inexact science so take it with a grain of salt.
That being said, the ones we see here I believe are California great horned owl (Bubo virginianus pacificus).
The California ones are among the smallest in size with the biggest being the ones up in Alaska and Canada.
Looking at the different subspecies is another reminder of how truly varied the habitats are that these guys can surve in. For example, there is a Desert great horned owl (Bubo virginianus pallescens) which, among other places, can be found here in California in the Mojave Desert. Very adaptable!
Member Submissions
Thank you to everyone who sent me photos of the birds they saw!
To lead off Sangeeta shared a very cool experience from GGP. In Sangeeta's words:
I am sharing pictures of a bird mist net experience at Middle lake. Students from SF State University had put up mist nets and I observed them weighing, banding, taking blood samples etc. They caught 3 song sparrows, 1 brown headed cowbird, 1 Wilson’s warbler, 1 American Robin and 1 Nutall’s woodpecker.
Next up George saw an oakland golf course duo - an acorn woodpecker and a steller's jay.
Over in Texas Nick checked in on this robin and robin nest
Aarsh sent a video showing off the bird sound in his neighborhood. Here is a screenshot
Punam snapped some pics of a baldie in san jose!
Kelly and baby John were back at it in their local pond in the east bay!
Sandy and Rick birded over in South Carolina and Georgia
Frank and Theresa did some birding in Rhode Island
May and Chad also saw some California quail and turkeys up in Sonoma
Dom birded all over Santa Barbara and a lil bit in Indiana
Katlyn birded in the grand tetons/ jackson area of wyoming
Emily and James birded locally and all the way in the Galápagos!! The DREAM
Adam, Janet, and I visited Dom and Lindsay down in SB for a bit of a birding weekend. I took a lot of photos, mostly poor ID photos, but including a handful of highlights.
Outside of the SB + Mt. Davidson birding I got in a bit of city birding, but I'll keep it brief because this is already a long one.. our official city animal
Last up if you stuck around this far you will be graced with this black-crowned night heron photo from adam. I hope your screen brightness is solid
Closeout
That's all; happy birding