Thanks Mike for sharing! It's interesting to see that others have noticed similar Red-tailed groupings. As Dominick mentioned, it seems plausible that local territorial pairs and/or juveniles might soar together in favorable conditions (to reestablish territories or hierarchies), before returning to their territories. It was certainly interesting to watch.
Thanks all for the comments - this is a nice learning opportunity for me.
Happy birding,
Zac
Sunday afternoon I spent a couple of hours photographing birds attracted by the ripening plums of a tree at the edge of Tilden. It is downhill near 580 Wildcat Canyon Road. This tree is in an ideal location for photographing birds since the main branches are almost level with the roadway. These plum trees appear at other locations in Tilden including in the hill above Jewel Lake. Here are some photos of some of the birds seen. Not seen yet, but spotted there last year at this time, Western Tanagers.
On Flicker Claude Lyneis
I forgot to report that most (if not all) of the redtails in both gatherings were juveniles. The social interactions we observed in 2019 make me wonder if they might pair-up before dispersing.
This sounds like a convention of local birds taking advantage of favorable flight conditions getting together in a little community meeting and re-establishing territorial boundaries rather than a migratory movement.
DM
My wife and I have witnessed two similar gatherings of red-tailed hawks, both at this time of year.
On the morning of 7/17/2019 I noticed 6 redtails flying over our yard and the hill behind our house. A while later, my wife returned from an errand and reported that their were lots of redtails soaring above Cummings Skyway. As we stood in our yard and watched, we realized that we were seeing more than 20 redtails at one time. I was able to count 17 with confidence three different times. That was in one area and I could see several more redtails by turning my head in either direction. They were soaring, swooping, and diving at high speed, sometimes across our deck right over our heads. They also interacted in mid-air. Chasing each other and sometimes rolling onto their backs to show their talons, or coming together "face-to-face", hovering briefly and then falling away. It was lovely and thrilling to see!
On the morning of 7/16/2023 I noticed 5 red-tailed hawks over our yard and the hill behind our house. More had joined by late morning and I was able to confidently count 9 redtails two different times. There may have been more. They did occasionally swoop over our deck, but we did not witness any of the social interactions that we had seen in 2019.
Mike Kellogg
Tormey (between Rodeo and Crockett)
PS:
Modest correction to the timing / numbers in my email below: I realized that the first group of soaring birds was 8 (6 together plus 2 further to the south) and that we saw 4 additional along Rifle Range instead of 2 as I said (plus the screeching juvenile). The overall count of 13 was the same, but I misrepresented when 2 of them were seen. Sorry about that.
Zac Denning
Albany
Yesterday, Jack Hayden and I birded Wildcat Regional Park from the Rifle Range Rd trailhead, covering portions of the Leonard trail (above Wildcat Trail) as well as the wooded east-west draws to either side of Leonard trail. It was a rewarding morning, with a high count of Lazuli Buntings, lots of Grasshopper Sparrows, close views of some very tame fledgling Rufous-crowned Sparrows, Ash-throated Flycatchers (in a previously documented breeding location), a kestrel, a male Western Tanager and an inadvertently flushed Great Horned Owl.
But one thing that seemed notable, was seeing Red-tailed Hawks moving in numbers that I'd usually associate with migration here in Sep-Oct. We'd been seeing 1-3 at a time throughout the morning (on perhaps 5 occasions), including 2 adults and one juvenile which we presumed were local breeders and their youngster.
As we returned along Wildcat Trail towards the bottom of Rifle Range Trail at around 11:30am, we were surprised to see a kettle of 8 Red-taileds soaring together, all adults! We at first only noticed a few of them, but the more we scanned that area of sky, the more we found. As we scanned much further to the south, we picked up an additional 2 more adults in that direction - with all 10 visible at once. Those birds were all moving SSE, soaring in circles, and as we walked back along Wildcat Trail, they disappeared from view far to the south. Perhaps 10 minutes later, we saw 2 additional adult Red-taileds, these much closer and moving east to west with more direct flight, obviously not part of the first large group.
Since before 11:30am, a juvenile had also been insistently screeching nonstop from a perch in the eucalyptus grove to the west of us, bringing the total to at least 13 unique individuals that we were sure of! To avoid double counting, we included only the 13 that we knew were unique individuals, though there could have been more.
Has anyone else been seeing Red-taileds in numbers? I read on Birds of the World that their migration is complex, but migration is generally described as starting later - with the earliest movements starting with birds much further to the north as I understand it. I'd be curious if anyone has insight into what's happening here, or if there's some precedent for a mid-July movement of Red-taileds?
Here's a link to our checklist, including photos and recordings of some of the highlights, as well as 2 of the Red-taileds seen before 11:30am (one adult, one juvie):
Happy birding,
Zac Denning
Hi birders,
According to the guidelines I may post once about a bird walk, so here I go!
I've organized a queer birder meet up this upcoming Sunday, July 20 at Albany Bulb. We will meet by the public restrooms at 9 am and roam the bulb for an hour. This is an informal event, as I am an amateur birder myself, so please bring binoculars and a good attitude.
Being queer is not a requirement, we would love to have any allies and curious bird enthusiasts join us. All ages welcome! Consider leaving dogs at home, or keep them on-leash throughout the event.
Thank you and I hope to see some of you on Sunday.
Kat Palermo
Berkeley, CA
Apparently someone on Alcatraz just photographed a Nazca Booby, adult, flying around inside the bay towards Angel Island. Fide Lucas Stephenson.
Very good information. However this paper...
https://academic.oup.com/auk/article/136/4/ukz049/5565029
found a Rufous/Allen's hybrid zone on the Oregon/California border 300
kilometers long and 90 kilometers wide. Detecting hybrids in the field
will not likely be easy, but we need to keep in mind the possibility that
some of the birds we identify as one species or the other, even those based
on a combination of field marks may be hybrids.
Having said that, I agree the bird in the excellent photos is likely
Allen's beyond the margin of error.
On Sat, 12 Jul 2025 10:16:59 -0700, "Peter Pyle via groups.io"
<ppyle@...> wrote:
Good subject right now and excellent posts.
Another reason the initial ALHU is a juvenile male is the heavy bronze spotting to the throat, whether or not there is iridescence as well. Juvenile females have cleaner white throats while adult females have cleanish white throats with a patch of iridescence in the center.
Outer rectrix width is indeed very useful, with little or no overlap within each age/sex group. So aging and sexing needs to precede analysis of rectrix width and, luckily, it is easy enough to do this based on the above characters.
Ethan's cautions and info on timing are spot on. There's a good paper by Howell and Gardali on this in Journal of Field Ornithology a number of years ago that should be easy to locate on line.
Cheers, Peter
On Jul 12, 2025, at 09:47, Ethan Monk via groups.io <z.querula@...> wrote:
?Hi,
Immature male feels safely supported by the iridescent gorget feathers coming in at the very side of the gorget (bottom of auricular-ish), and the more inner rectrices often have more green showing in females. So for example on the R2 (second rectrix from center) you will often have green sandwiched between the rufous and black
on the females. The green will often be more extensive on the R1 in females, etc.
When it comes to the finer points of the ID, which is importantly done based on age/sex, I think Zac's explanation did a good job.
I will say, the width of the outermost rectrix-- R5 --has burned me before. The apparent width of that tail feather can change a lot based on the angle of the photo, and I just stay away in cases where it feels even vaguely ambiguous. But I know people better than me disagree.
As this conversation handily illustrates, non-adult male Rufous and Allen's Hummingbirds are generally not identifiable under standard field conditions, which is why Allen's Hummingbird flags as "rare" in eBird for Contra Costa County in late June. Most adult male Allen's depart earlier in the month, so it will get really hard to
find a "safe" Allen's by the end of June. Obviously, Allen's are still around, so if you go around photographing tail feathers you will find plenty of Allen's (females and immatures) right after they flag in eBird, but it's worth noting Rufous Hummingbirds start to show up at end of June, too. By second week of July, Rufous
Hummingbirds are very present in the interior parts of the East Bay. And presumably the more coastal parts too, but harder to say for obvious reasons!
Ethan
On Fri, Jul 11, 2025 at 6:59?PM Bob Lewis via groups.io <RLewis0727@...> wrote:
Wow, I just sent Claude a note saying it was a female. Reasoning being the tips of R3-R5 are bright white, and immature male is more tan-tipped. I do think the R5 is quite narrow, supporting Allen's. If indeed it's a male, then I think Zac's comments regarding the absence of a notch (or nipple-like tip) is convincing, and it's
an Allen's. But obviously I have no real clue!!Bob
On Friday, July 11, 2025 at 06:48:58 PM PDT, Zac Denning via groups.io <zdenning1@...> wrote:
Hey Claude,
This is a juvenile male, so the ID is a bit more subtle than for adult males. Unfortunately, by this time of year, my understanding is that the adult males have mostly left the scene, so the tougher birds are what were left with ...
Others are more expert, but for what it’s worth, here’s my take:The R2 feather (next to innermost tail feather in your 3rd shot) appears to be missing the slight notch that juvenile male Rufous would usually show. If you happen to also have a shot of the outermost tail feather that’s separated enough from the others to see the
feather width, that might help clarify further.
In terms of whether the 3rd photo (with spread tail) meets the reviewers’ threshold for listing as Allen’s, I’m not sure. The default right now would be listing all these birds as a slash (Allen’s/Rufous Hummingbird).
If you don’t get definitive feedback from a reviewer/expert on this email thread, and if you have the reviewer’s contact, you could list as a slash on eBird, reach out to them, then wait for confirmation before proceeding with a more definitive ID. Otherwise, you could try listing as Allen’s, and say in the eBird description that
you’re seeking reviewer feedback. If your reviewer responds (whatever the outcome), please be sure to thank them for their unpaid work to keep eBird data accurate! It’s not an easy job.
Maybe someone has another suggestion, but that’s usually how I’d usually handle this type of situation.
I hope that helps.
Zac DenningAlbany
On Fri, Jul 11, 2025 at 5:44?PM Claude Lyneis via groups.io <cmlyneis@...> wrote:
After seeing several eBird reports of Allen’s Hummingbirds in U.C. Blake Garden I thought I would try again to get some definitive photos that would pass expert judgement and not have to be labeled Allen’s/Rufous. A couple of these photo show good detail of the tail feathers, but is that enough? There were several of these
Hummers buzzing around and at least one Anna’s. Blake Garden seemed a rather magical place hidden away in Kensington.
Here is an album with four photos of the bird.
<54648983475_d4aa3e69a4_c.jpg>
Allen's Hummingbirdflic.kr
Claude Lyneiscmlyneis@...://www.youtube.com/bhsvideodadFlickr Photos at https://flic.kr/ps/36it5P
--
Joseph Morlan, Pacifica, CAGood subject right now and excellent posts.
Another reason the initial ALHU is a juvenile male is the heavy bronze spotting to the throat, whether or not there is iridescence as well. Juvenile females have cleaner white throats while adult females have cleanish white throats with a patch of iridescence in the center.
Outer rectrix width is indeed very useful, with little or no overlap within each age/sex group. So aging and sexing needs to precede analysis of rectrix width and, luckily, it is easy enough to do this based on the above characters.
Ethan's cautions and info on timing are spot on. There's a good paper by Howell and Gardali on this in Journal of Field Ornithology a number of years ago that should be easy to locate on line.
Cheers, Peter
Thanks Ethan - very helpful info!
Zac
Hi,
Immature male feels safely supported by the iridescent gorget feathers coming in at the very side of the gorget (bottom of auricular-ish), and the more inner rectrices often have more green showing in females. So for example on the R2 (second rectrix from center) you will often have green sandwiched between the rufous and black on the females. The green will often be more extensive on the R1 in females, etc.
When it comes to the finer points of the ID, which is importantly done based on age/sex, I think Zac's explanation did a good job.
I will say, the width of the outermost rectrix-- R5 --has burned me before. The apparent width of that tail feather can change a lot based on the angle of the photo, and I just stay away in cases where it feels even vaguely ambiguous. But I know people better than me disagree.
As this conversation handily illustrates, non-adult male Rufous and Allen's Hummingbirds are generally not identifiable under standard field conditions, which is why Allen's Hummingbird flags as "rare" in eBird for Contra Costa County in late June. Most adult male Allen's depart earlier in the month, so it will get really hard to find a "safe" Allen's by the end of June. Obviously, Allen's are still around, so if you go around photographing tail feathers you will find plenty of Allen's (females and immatures) right after they flag in eBird, but it's worth noting Rufous Hummingbirds start to show up at end of June, too. By second week of July, Rufous Hummingbirds are very present in the interior parts of the East Bay. And presumably the more coastal parts too, but harder to say for obvious reasons!
Ethan
Wow, I just sent Claude a note saying it was a female. Reasoning being the tips of R3-R5 are bright white, and immature male is more tan-tipped. I do think the R5 is quite narrow, supporting Allen's. If indeed it's a male, then I think Zac's comments regarding the absence of a notch (or nipple-like tip) is convincing, and it's an Allen's. But obviously I have no real clue!!
Bob
Hey Claude,
This is a juvenile male, so the ID is a bit more subtle than for adult males. Unfortunately, by this time of year, my understanding is that the adult males have mostly left the scene, so the tougher birds are what were left with ...
Others are more expert, but for what it’s worth, here’s my take:
The R2 feather (next to innermost tail feather in your 3rd shot) appears to be missing the slight notch that juvenile male Rufous would usually show. If you happen to also have a shot of the outermost tail feather that’s separated enough from the others to see the feather width, that might help clarify further.
In terms of whether the 3rd photo (with spread tail) meets the reviewers’ threshold for listing as Allen’s, I’m not sure. The default right now would be listing all these birds as a slash (Allen’s/Rufous Hummingbird).
If you don’t get definitive feedback from a reviewer/expert on this email thread, and if you have the reviewer’s contact, you could list as a slash on eBird, reach out to them, then wait for confirmation before proceeding with a more definitive ID. Otherwise, you could try listing as Allen’s, and say in the eBird description that you’re seeking reviewer feedback. If your reviewer responds (whatever the outcome), please be sure to thank them for their unpaid work to keep eBird data accurate! It’s not an easy job.
Maybe someone has another suggestion, but that’s usually how I’d usually handle this type of situation.
I hope that helps.
Zac Denning
Albany
Hey Claude,
This is a juvenile male, so the ID is a bit more subtle than for adult males. Unfortunately, by this time of year, my understanding is that the adult males have mostly left the scene, so the tougher birds are what were left with ...
Others are more expert, but for what it’s worth, here’s my take:
The R2 feather (next to innermost tail feather in your 3rd shot) appears to be missing the slight notch that juvenile male Rufous would usually show. If you happen to also have a shot of the outermost tail feather that’s separated enough from the others to see the feather width, that might help clarify further.
In terms of whether the 3rd photo (with spread tail) meets the reviewers’ threshold for listing as Allen’s, I’m not sure. The default right now would be listing all these birds as a slash (Allen’s/Rufous Hummingbird).
If you don’t get definitive feedback from a reviewer/expert on this email thread, and if you have the reviewer’s contact, you could list as a slash on eBird, reach out to them, then wait for confirmation before proceeding with a more definitive ID. Otherwise, you could try listing as Allen’s, and say in the eBird description that you’re seeking reviewer feedback. If your reviewer responds (whatever the outcome), please be sure to thank them for their unpaid work to keep eBird data accurate! It’s not an easy job.
Maybe someone has another suggestion, but that’s usually how I’d usually handle this type of situation.
I hope that helps.
Zac Denning
Albany
After seeing several eBird reports of Allen’s Hummingbirds in U.C. Blake Garden I thought I would try again to get some definitive photos that would pass expert judgement and not have to be labeled Allen’s/Rufous. A couple of these photo show good detail of the tail feathers, but is that enough? There were several of these Hummers buzzing around and at least one Anna’s. Blake Garden seemed a rather magical place hidden away in Kensington.
Here is an album with four photos of the bird.
Claude Lyneis
cmlyneis@...
A few observations east of Danville Blvd, 1/2 mile north of new Tesla charging station.
Today, there was male CA quail with 3 chicks feeding on grounded seeds discarded from our squirrel proof elevated feeder.
The chicks were a tiny size that would have fit in a typical chicken egg.
The chicks searched and fed on seeds super close to the male as he fed ravenously.
Must be a 2nd brood?
Our hummers drained the feeder very quickly in the last week.
Seems like Bwick's wrens are more common here than in last 4 years.
To my surprise I discovered two wood ducks at Jewel Lake late morning today. They appeared to be immature. After a couple of minutes they disappeared under the overhanging bushes opposite the bench on the west side of the lake. I'm generally on the lookout for wood ducks at Valle Vista but not Jewel Lake. The much more common mallards were also present.
Mary Korn
Kensington
Here is a link to a video I took 5 days earlier than the photos and eBird checklist posted above. It gives a better idea of the spectacle of the nesting ELEGANT and CASPIAN TERNS on the Richmond breakwater. This was take with my phone in a digiscope setup during very windows conditions, hence the shakiness. The first segment is at full speed and the second is at 1/2 speed and zoomed in a bit.
Tony Brake
Point Richmond
Hi Tony,
Thank you for sharing your observations.
When you see Elegant Terns, please look for red or orange leg bands. International Bird Rescue conducted a large-scale rescue operation in summer 2021, and over 3,000 Elegant Tern chicks passed through our hands. We are eager for reports on this cohort.
<
https://images.app.goo.gl/EFqmfXqTtJVB6XXJA>
Thanks,
JD