Date: 10/26/26 11:57 am From: Ronald- Thorn via groups.io <Tronthorn...> Subject: [pen-bird] Cocos Booby on San Francisco Bay
One hour ago, I was scanning the salt marsh from the observation deck at the end of Canvasback Way in Redwood Shores. I was surprise to see a Cocos Booby flyingnorth over the bay. I watched the Cocos Booby, where near the San Mateo Bridge it gained elevation and crossed over the bridge. Yesterday, there was a record highof ( 18 ) Cocos Boobies on Southeast Farallon Island.
Ron Thorn
Date: 10/25/26 5:13 pm From: Barbara Kossy via groups.io <bkossy...> Subject: [pen-bird] Half Moon Bay by Kayak
I was happy to get out on the ocean in our double kayak with my husband on a sunny and calm October afternoon. Just last week the harbor was packed with Brown Pelicans. There was hardly standing room on the jetties. Today we saw long stretches of empty guano covered rock, with just a Western Gull here and there, evenly spaced. In the area where we typically see the Northern Gannet (absent at about 1:30 pm) were a smattering of Brandt's Cormorants, 4 Black Oystercatchers, a few Black Turnstones, and about 20 Pelicans. Out on the waters of Half Moon Bay we paddled past flocks of 20 Western Grebes, team foraging (no Clark's were noticed.) At least 2 Common loons flew over, one heading NW and the other East. Out towards the red buoy at about 1.8 miles was a smallish (comparatively) group of birds feeding. There were sitting and low-flying shearwaters. When I got a look they were the Black-vented Shearwaters, smaller than sootys, and with the white belly and charcoal smear underwings. In the group were Double-crested Cormorants, Common Murres, Western Gulls, and Brown Pelicans. A line of 12 Surf Scoters flew low over the water and NW. Paddling along I think I got a glimpse of a pair of Short-billed gulls on the water. Smaller than Westerns, cuter look, white head, black with either back dot or perhaps ring on the bill. We were pressing into the wind, so I didn't get a great look. Elegant terns were still in the harbor. They looked especially dapper sitting on top of spherical red buoys. I looked around for a possible Royal Tern. No luck there. The Caleb sunken tug hosted some Double-crested Cormorants, but no night herons. I didn't check the inner harbor for the Yellow-Crowned Night Heron. (I forgot!!) The ocean outside of the harbor was pleasantly more birdy than I expected. Other highlights included being followed by a sea lion close to 2 miles out near the red buoy that held 6 or 8 sea lions. It seemed a bit too interested in us, but people were fishing in small boats not far away. We slapped the water with our paddles to warn it off after it swam under the kayak a couple of times.
Aside from the Yellow-browed Warbler in Moss Beach, highlights from a fair amount of coverage over the past ten days or so in San Mateo included Hooded, Blackburnian, Black-and-white, Palm, and Tennessee (3x) warblers, a White-winged Dove, a Yellow-headed Blackbird, a somewhat early Slate-colored Junco, a handful of Nashvilles and FOS White-throated Sparrows and things, a very surprising unseasonable pulse of Swainson's Thrushes, and (presumed) last-of-season Western Flycatcher, Wilson's Warbler, and so on. Red-breasted Nuthatches have died down somewhat and are about half or two-thirds as numerous as they were three weeks ago. Red Crossbill numbers have really picked up, however, and they are nearly everywhere. So far, all the crossbills I have heard have sounded fine for Type 2 to me, which seems to be the dominant type locally in this year's irruption.
On Tuesday 10/13, I started at Mori Pt, where phenomenal numbers of sparrows at dawn included the first White-throated Sparrow I have noted in the county this fall. (I also had one the previous day in Santa Cruz.) I left San Mateo Co. briefly to go see the Sulphur-bellied Flycatcher in S.F., which was a walk-up bird, and then birded the rest of the north coast from Thornton SB to Montara. A Warbling Vireo and two Yellow Warblers were along upper Calera Ck. Entering the willows at lower Calera Ck, I heard a Northern Waterthrush chipping and while trying to pish it in for views, I heard a different sharp thin chip note and eventually got good views of a bright Tennessee Warbler. Shortly afterward I learned that the waterthrush had been found four days previously by Cdric Duhalde. Meeting up with Cdric, we birded the Farallone Willows in Montara, where Cdric spotted a Nashville Warbler. Two were together here on 10/5. Singles of Western Flycatcher on lower Sunshine Valley Rd and Wilson's Warbler along Pilarcitos Ck behind the lowest pumpkin patch were the only other Neotropical migrants I had all day.
On Thursday 10/15, I found few passerine migrants in a full day of coverage of the central coast from Pescadero to Half Moon Bay under clear skies all day, with a light NW breeze in the morning picking up substantially by midafternoon. A group of about 25 Greater White-fronted Goose flew out of Pescadero Marsh at dawn. A single Yellow Warbler and a Nashville Warbler were behind the gas station in Pescadero, where two Nashvilles were on 10/7. A Palm Warbler, my second this fall in the county, was along Butano Ck Cutoff near the high school. The sole Neotropical migrant on all of Tunitas Ck was a getting-late Swainson's Thrush near the mouth; a Black-crowned Night Heron at the same spot was notable locally. At the Johnston House I had my second White-throated Sparrow of the fall in the county, and a Warbling Vireo was behind Mariners Church in Half Moon Bay. Yet another Nashville Warbler was along Pilarcitos Ck at Oak Ave Pk. I saw relatively few (c. 5) Red-breasted Nuthatches all day.
On Friday 10/16, I birded north Half Moon Bay from Pillar Point to Miramar in the morning. The conditions were bizarre with a fairly strong gusty east wind and very high temperatures, 74 F in Half Moon Bay before sunrise (!). Morris the Northern Gannet was present on the inner breakwater. At Princeton Willows, a striking female Hooded Warbler popped out near the western end of the patch and right off the road to Mavericks in response to pishing. This was a long-awaited self-find in the county! At eight more stops in northern Half Moon Bay I had zero additional Neotropical migrants.
On Saturday 10/17, I birded the south coast from Weed Farms to Pescadero in the morning. Weed Farms was below its usual standard, being dry with low sparrow numbers. However, the fields north of Cascade Ck have been burned again; while they had few open-country birds on this day, after the last burn a couple years back these fields were extremely productive, and they should be checked through the next couple months for longspurs, Horned Lark, and similar. Excellent sparrow numbers at Pie Ranch included a junco showing characteristics of the Slate-colored group. (I think of the Slate-colored group as encompassing both Boreal Slate-colored, hyemalis/carolinensis, and Cassiar Slate-colored, cismontanus; for female-types like this bird I generally prefer not to say anything more specific than Slate-colored group in the broad sense, absent excellent photos etc.) This is a rather early date and indeed I do not know of many documented records for the county before October 20, though I am sure there are some older ones of which I am not aware. I was surprised to learn that ridgewatchers in Marin, Santa Cruz, and elsewhere have reported Slate-colored Juncos this year starting on September 30. No doubt these are side effects of increased coverage aimed at irruptive montane birds, but it is still interesting. I average 12 Slate-colored Juncos per year on the San Mateo coast, usually in NovDec. Also at Pie Ranch was a Warbling Vireo, and a Black-throated Gray Warbler was along Whitehouse Ck at Costanoa. Along lower Gazos Ck, birded from the gas station parking lot, a very dull Blackburnian Warbler was with a small flock. I think that puts the tally at 66 BlackburnianBlackpoll this year in the county. Still a little while left for one of them to pull ahead and break the tie!
On Sunday 10/18, Chris Henry and I started at Ano Nuevo, where we had single Yellow and Black-throated Gray warblers, as well as several flocks of Red Crossbills, including on the outer part of the peninsula. I believe most or all were Type 2, as most of the invaders have been this fall. We then birded Santa Cruz Co. for ten hours and had nothing better than a single Palm Warbler because Santa Cruz is not as good a county as San Mateo is. To prove the point, while we were off seeing no birds in Santa Cruz, Ryan Mense found a beautiful male Black-throated Blue Warbler at the previous day's Blackburnian spot :)
On Monday 10/19, I birded pumpkin patches and odds and ends for sparrows and weedfield birds around Half Moon Bay for most of the day. Numbers of Golden-crowned and Lincoln's sparrows were very low, especially with far fewer Lincoln's (812 all morning) than expected by this date. Among the very numerous White-crowned Sparrows were several Gambel's, including three together at Andreotti Family Farms. One each of Nashville and Yellow warblers were at the Farallone Willows in Montara. A couple scattered Red Crossbills were all Type 2, I think. An access point to Pilarcitos Ck that I rarely check, along the north side by Hwy 92 x Hwy 1, had a large flock that included a nice-looking female Black-and-white Warbler.
On Tuesday 10/20, I started in San Francisco and spent far longer there than expected because Caitlin Chock and I had a Yellow-green Vireo and a Blackburnian Warbler in the arboretum. Rushing to get through a couple spots on the northern San Mateo coast on the way back, a Yellow Warbler was at Thornton SB and the Northern Waterthrush discovered on 10/9 by Cdric Duhalde was still at Calera Ck.
On Wednesday 10/21, I birded the central coast from Pigeon Pt to Half Moon Bay under high overcast and light shifting winds for the most of the day, strengthening with a couple light rain showers in the late afternoon. At the residences on eastern Pigeon Pt Rd, a White-winged Dove was with Eurasian Collared-Doves on the wires and a calling Northern Mockingbird was down near the small pond. Northern Mockingbird is rare on most of the San Mateo coast, but one was at this same location last December. At Pescadero Marsh, a Blue-gray Gnatcatcher was with a small flock in the riparian and I was surprised to hear a Swainson's Thrush calling. I was still more surprised to hear another Swainson's Thrush along Butano Ck and then others on San Gregorio Ck, at the Verde Rd Pond, and two (!) along Miramontes Ck. I had a late on 10/15 and otherwise none since 10/6 in the county, so having a minimum of six individuals today was truly astonishing. To make sure I had not developed a recurrent Swainson's Thrush auditory hallucination, I worked hard to obtain views of the calling bird at Miramontes Ck and only in doing so did I realize two individuals were present. A late pulse of Swainson's Thrush like this one is very interesting and quite noteworthy. Possibly related were single birds reported the following day (10/22) on Corona Hill, SF, and on Southeast Farallon Island. Reaching Pescadero, two Tennessee Warblers were together (more or less; each seemed to staking out one bush) in bottlebrushes near the end of Water Ln and an adult male Black-throated Gray Warbler was at the Stage Rd bridge over Pescadero Ck with a large flock. A Nashville Warbler was along Tunitas Ck just above the dip. Red Crossbills were noted at Water Ln, Goulson St, San Gregorio Ck, and Mariners Church. The blackbird roost along Verde Rd had more than five times its usual number of blackbirds, even when I stopped at 2:20 p.m., well before the usual peak time. Scanning through these I noted a high proportion of Tricolored Blackbirds with at least 1,500 individual trikes in 2,0002,500 total blackbirds. The remainder were mostly Red-wings, with a couple dozen Brewer's and a single Yellow-headed Blackbird. The Yellow-headed was a bright HY bird and only the second I have seen on the San Mateo coast.
On Thursday 10/22, there was a heavy low overcast with rain showers over the central coast, so I started in neighborhoods in El Granada. I rarely visit these neighborhood patches before November. Passerine numbers were a little lower than usual in these locations, but that may be a result of the early date. At Princeton Willows, I relocated the female Hooded Warbler from last week, deeper in the willows, and others also relocated it the following day (10/23). With a weeklong stay at this late date, there is a chance this bird may attempt to winter. Checking neighborhoods in Pillar Pt Bluff southwest of Fitzgerald, a Palm Warbler was at the corner of Park Way and Orval Ave. Then I checked upper San Vicente Ck at Ember Ridge and lightning struck with a beautiful Yellow-browed Warbler. Details on the Yellow-browed Warbler are on eBird and elsewhere and will be submitted to the CBRC.
On Friday 10/23, I spent much of the day seeing the Yellow-browed Warbler with others, but also birded other locations on the central coast between Pillar Pt and Hwy 92. A group from San Luis Obispo including Kilian Hampl, Reef Comer, Ann Stockert, and perhaps others found an immature Yellow-crowned Night Heron at Pillar Pt; this is the fifth county record and the first away from Coyote Pt and Ano Nuevo, which have two records each. Morris was present as well. A Black-throated Gray Warbler continuing from the previous day at the Yellow-browed Warbler spot was the only Neotropical migrant all day.
Here are some details on today's Yellow-browed Warbler along San Vicente Ck at Ember Ridge, Moss Beach, San Mateo County. First off, it was seen more or less continuously (never absent for more than about 15 minutes) today from 11:15ish, when I found it, through around 5 pm. As far as I know, it was not seen after 5 pm. It calls fairly regularly, sometimes in flight, and is often located by call. It is extremely active and stays at or above eye level. It was occasionally with loose flocks of gleaners, but not tightly tied to them. Fortunately, it remained quite faithful to the willows around (37.5245821, -122.5039195); I think the furthest it ranged was about (37.52411, -122.50385). The weather overnight looks reasonably promising for the bird to remain, for whatever that's worth; the Alpine bird stayed two days (10/2425/2019) and the BC bird stayed seven (10/1824/2019).
Birders are permitted to walk around the entirety of the Ember Ridge stables area. However, we are NOT permitted to park there. *Please park along Etheldore St* (e.g., around 37.52247, -122.50647) and walk about 5 minutes up the dirt road to the stakeout. Whatever you do, do NOT park in the stable's parking lot, where the bird was seen. Ember Ridge is a working stable and there are people walking horses around and so forth. They have all been okay with the presence of birders so far, even at times when there were more than 50 people there today, but please stay out of the way as much as possible and be super nice to them and all that.
Identification in this genus is of course challenging. In a North American context, the only Yellow-browed-type Phylloscopus recorded in Alaska are Yellow-browed (of course) and Pallas's Leaf, and Pallas's is readily eliminated by the San Mateo bird's lack of a bold central crown stripe, lack of a contrasting pale rump patch, less compact structure, etc. Other potential vagrants to North America, as yet unrecorded, include Two-barred and Hume's warblers. Two-barred is longer-billed, longer-tailed, and lacks contrasting pale tips/edges to the tertials, which the San Mateo bird shows; Hume's is supposed to lack a pale base to the lower mandible, which the San Mateo bird has. And, more importantly, the San Mateo bird has been giving "suweet" calls, kind of like the ascending call ("male position note") of a Western Flycatcher but more symmetrical, i.e., with more downsweep before the upsweep, and without any break in it. This is unlike the calls of Two-barred, Hume's, and I believe also rules out a bunch of really implausible things like Brook's Leaf Warbler, Emei Leaf Warbler, etc.
Photographs and audio are on eBird (e.g., https://ebird.org/checklist/S404567035), and further written details will be added as well. This is the second for California after a bird found by Todd Easterla in Markleeville, Alpine Co., in 2019. Consider submitting documentation to the California Bird Records Committee (https://www.californiabirds.org/report_sighting.html) if you see it.
Spending all day with this bird and so many awesome birders from around the Bay Area was the birding experience of a lifetime! Good luck to all chasers!!!
Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________
From: <peninsula-birding...> <peninsula-birding...> on behalf of Marty Freeland via groups.io <martinf3...>
Sent: Thursday, 22 October 2026 11:46:32
To: 'Peninsula Birding' <peninsula-birding...>; CALBIRDS <calbirds...>
Subject: [pen-bird] Putative YELLOW-BROWED WARBLER
Phylloscopus warbler appearing to be a YELLOW-BROWED in Moss Beach, San Mateo Co. photos and further details forthcoming
Date: 10/21/26 11:35 am From: Dorian Anderson via groups.io <thespeckledhatchback...> Subject: [pen-bird] Recent bird photos, a giveaway, and a request
All -
Here are 17 images from the fall plus 2 holdovers from the summer. There also is a screenshot from my Bay Area biking eBird account. As you can see, it's been a productive ~6 weeks with 8 birds added to my running total (375). I've biked over 900 miles in that span (and near 2,600 for the year), so yay for me. I've also pushed my San Mateo bike list to 309, and my SF bike list grew to 298 with yesterday's Lapland Longspur and Black-vented Shearwater. Santa Clara lagging a bit with 245. 852 total ticks across the the peninsula counties - woo hoo!
Anyway......do you see that framed painting of the Coppery-tailed (i.e. formerly Elegant) Trogon in the gallery? It's free to the first person who claims it from my apartment. I'm near the intersection of Delaware and Peninsula, at the interface of San Mateo and Burlingame. Email/call for specifics.
Lastly, if you've bought, read, and enjoyed my book, I'd greatly appreciate a review on Amazon, Goodreads, or other online platform. Star ratings are super, but a few lines of explanatory text really elevate the review. I'll thank you in advance for whatever you can offer.
It's been fun to be around for most of the fall, but that run comes to an end on Saturday, when I leave to lead a three-week photo tour in South Africa. A highly undesirable assignment, I know......
Date: 10/16/26 4:10 pm From: Ronald- Thorn via groups.io <Tronthorn...> Subject: [pen-bird] Lewis's Woodpecker in Belmont
At the south end of the public access trail off of Sem Lane in Belmont, I looked up to see a Lewis's Woodpecker flying south overhead. There were two sightings of Lewis'sWoodpeckers in San Francisco yesterday. A late Lazuli Bunting was along the trail. An early morning skywatch from home in Redwood Shores, I noted the first arrival of amale Bufflehead flying over the Redwood Shores Lagoon. During the week, a juvenile Parasitic Jaeger was on the bay at Coyote Point.
Ron Thorn
From: Jane Tatchell <Jane...>
To: "peninsula-birding"<peninsula-birding...>
Date: Thu, 15 Oct 2026 17:45:04 -0700
Subject: Re: [pen-bird] House Finch with a deformed beak?
Given that this looks like Avian Keratin Disorder, I'll take down my feeders for a couple of weeks.
Since you have a long-term perspective and have been seawatching longer than perhaps anyone else in the county. Would you say that this Black-vent incursion is the biggest ever you have seen? There were numbers in Monterey Bay last week that suggested that a huge part of the world population of this bird is now in our area, just like your observation. Estimates range from 46,000 to 120,000 pairs of this species, as such your observation may mean that half the breeding population (using the lower estimate) is in San Mateo right now, that is amazing. But I don’t have a handle on if it has happened like this before. I don’t know what it was like during the 81-82 El Niño.
From: <peninsula-birding...> <peninsula-birding...> On Behalf Of Ronald- Thorn via groups.io
Sent: Thursday, October 15, 2026 2:49 PM
To: Peninsula Birding <peninsula-birding...>
Subject: [pen-bird] Moss Beach seawatch 10/14
Yesterday, I did a seawatch from Moss Beach. I was amazed in the large feeding frenzies spread out over the water. During the three hour seawatch is a partial list of what
was noted. No surprise that the dominant species were the Black-vented Shearwaters. I was doing one minute counts, as the Black-vented Shearwaters were moving
north through the feeding frenzies. A tally of ( 48,460 ) Black-vented Shearwaters. A single Sooty Shearwater was all I could note. Sooty Shearwaters have been scarce
in numbers south to Monterey County looking at seawatch reports from others. Southbound migrants were Surf Scoter ( 25 ), Red-necked Grebe ( 1 ), Red-throated
Loon ( 9 ), Pacific Loon ( 6 ). There was a high of ( 42 ) Parasitic Jaegers southbound. A single Pomarine Jaeger. A very low number of only ( 4 ) Common Murres.
Date: 10/15/26 11:48 am From: Ronald- Thorn via groups.io <Tronthorn...> Subject: [pen-bird] Moss Beach seawatch 10/14
Yesterday, I did a seawatch from Moss Beach. I was amazed in the large feeding frenzies spread out over the water. During the three hour seawatch is a partial list of whatwas noted. No surprise that the dominant species were the Black-vented Shearwaters. I was doing one minute counts, as the Black-vented Shearwaters were movingnorth through the feeding frenzies. A tally of ( 48,460 ) Black-vented Shearwaters. A single Sooty Shearwater was all I could note. Sooty Shearwaters have been scarcein numbers south to Monterey County looking at seawatch reports from others. Southbound migrants were Surf Scoter ( 25 ), Red-necked Grebe ( 1 ), Red-throatedLoon ( 9 ), Pacific Loon ( 6 ). There was a high of ( 42 ) Parasitic Jaegers southbound. A single Pomarine Jaeger. A very low number of only ( 4 ) Common Murres.
Ron Thorn
Date: 10/14/26 10:07 am From: maliadances via groups.io <maliadances...> Subject: [pen-bird] San Mateo County Cumulative Year-list Report for --- September 2026
*Greetings Pen-birders,*
San Mateo County birders confirmed a total of 15 species that were new for the year by the end of September. This brings the total species confirmed by the end of the ninth month to 324. This is the 2 nd highest end of September total since this report began in 2009, with 2015 ending at 325, one bird species higher! In reading the following, please note, the number in parenthesis next to the bird name is the rarity code assigned for San Mateo County birds. *From the link below* , you can *see definitions for the rarity codes,* *download a checklist* which shows seasonality, frequency, and county breeding information, *find a full list of the birds* observed so far in 2026 *, plus* *all monthly reports going back to 2009.*
*Here are the new birds for September, their finders and locations where found:*
WHITE-WINGED DOVE (5) was found by Vanderpoels, John, William, Mark and Jim at Pillar Point Harbor. Peter Metropulos encountered a PECTORAL SANDPIPER (5) in the creek-bed at Venice Beach. BLACK TERN (5) was photographed by Cricket Raspet at Pillar Point Harbor. LEWIS’S WOODPECKER (4) was called out by Alvaro Jaramillo and Chris Hayward, and seen by others, during a skywatch at a location along Skyline. Dorian put word out he had a DUSKY FLYCATCHER (5) while bike-birding at Cypress Lawn Cemetery. TROPICAL KINGBIRD (4) was spotted on the wires above the Mavericks parking area by Chris Hayward and Kent Forward. Two groups at two different locations, on the same day, observed CLARK'S NUTCRACKER (6). One group was Ron Thorn and Leonie Batkin at Cypress Lawn Cemetery. The other group included Alvaro Jaramillo, Caitlin Chock, Chris Hayward, Eli Gross, Jari Toivanen, Liam Murphy, Malia DeFelice, Marty Freeland, Michael Long who spent 4 hours skywatching at a location on Skyline. There Eli called out the 1 st nutcracker then later Liam called out a 2 nd nutcracker. GRAY CATBIRD (6) was discovered by Nathan Malick and Chris Hayward at Seaside School Rd. in San Gregorio. Two different locations each produced EVENING GROSBEAK (4) for Ben Golet at Gazos Creek and Kent Forward at Purisima Creek Redwoods on the same day. Jari Toivanen was the finder of the LARK BUNTING (5) at the seed patch along the trail to Mavericks Beach. While visiting Coyote Point County Park, a VESPER SPARROW (4) was found and photographed by Terry Crowe. Michael Long located a BLACKBURNIAN WARBLER (4) along Canyon Rd. in Pescadero. Darlene McNeil and Todd McGrath had the first CHESTNUT-SIDED WARBLER (4) along Gazos Creek Rd. Leonie Batkin and Ron Thorn detected a BLACKPOLL WARBLER (4) at Cypress Lawn Cemetery. A group including Kaiting H., Marty Freeland, Michael Long and Tino Castillo espied a PRAIRIE WARBLER (5) at Año Nuevo.
*Birding San Mateo County:* There are plenty of ways to see birds. Did you know *The San Mateo County Bird Alliance leads birding Field Trips* on a regular basis? To join a field trip, check out their schedule here: http://www.sequoia-audubon.org/fieldtrips.html
*Alvaro’s Adventures runs offshore pelagic trips* *now through November,* with many seabird, whale and sea-life finding trips out of Half Moon Bay and other ports. Alvaro’s pelagic schedule here: https://www.alvarosadventures.com/pelagic-dates-2026.html
*California’s First Statewide Breeding Bird Atlas* *-* This landmark effort is being led by *California Bird Atlas* ( https://www.californiabirdatlas.org/ ) ( CBA), an independent nonprofit, in collaboration with state agencies, thousands of volunteers, and dozens of partner organizations. All birders are now officially invited to join the project by visiting the new *California Bird Atlas eBird website* ( https://ebird.org/atlascalifornia/home ). Simply click “ *Join Project* ” ( or “Log in to Join Project”) and you will automatically be able to contribute checklists to the Atlas project. The Atlas is fully integrated with the eBird mobile app. If you submit checklists on mobile, this *Quick Start Tutorial video* ( https://www.youtube.com/shorts/8Z3kbqiO9rw ) provides a brief overview.
*To stay informed of the latest local bird news, consider creating an account with both Peninsula Birding (Pen-bird) and eBird.* To join eBird, simply go to https://ebird.org/home and create an account. To join the Peninsula Birding group, join here: https://groups.io/g/peninsula-birding You can post your sightings there and be kept informed of sightings throughout the county including discussions about birds, population trends, where-can-I-find topics, events, field trips, webinars, pelagic trips and conservation issues. You can engage with other members of the birding community and can connect with online/offline discussions.
*This Report:* As a volunteer for the San Mateo County Bird Alliance I gather content for this report, each month, by primarily using eBird and Pen-bird. When posting to Pen-bird, please include the location and date of your sighting in either the subject line or in the body of your email. If you don’t use eBird or Pen-bird, you can always email me directly. Thank you!
If you have questions or comments regarding this report, or if I missed something,
Date: 10/13/26 6:54 am From: Ronald- Thorn via groups.io <Tronthorn...> Subject: [pen-bird] Skywatch sightings, Prairie Falcon, Mountain Bluebird 10/12
Yesterday morning, I did a skywatch at Skyline Memorial Park. Finally no fog! I focus mostly on birds in flight over the Santa Cruz Mountains. Here is a partial list of whatwas noted in the park. Double-crested Cormorant ( 2 ), are rarely noted over the mountains, Red-tailed Hawk ( 2 ), Prairie Falcon ( 1 ) southbound, Golden Eagle ( 2 )near Scarper Peak, Band-tailed Pigeon ( 372 ), Mountain Bluebird ( 1 ) male briefly landing in a tree nearby before taking off and headed south towards Highway 92,Western Bluebird ( 5 ), Varied Thrush numbers increasing with ( 106 ), American Robin ( 31 ), Yellow-rumped Warbler ( 5 ), Western Meadowlark ( 3 ), Brewer's Blackbird( 7 ), Purple Finch ( 12 ), House Finch ( 18 ), Red Crossbill ( 35 ), Pine Siskin ( 2 ), Lesser Goldfinch ( 12 ). Later checking out crown sparrows through-out the park, therewas the first White-throated Sparrow I have noted for the fall.
Ron Thorn
Date: 10/11/26 10:06 am From: Chris M. via groups.io <chrismac...> Subject: [pen-bird] Big Sit today
Come and join us at Pescadero Marsh today (till 3 pm) for the Big Sit. Even better, pledge an amount per species recorded - anything, small or large, will help to fund the SMCBA's work - education, conservation, showing people how bird-wonderful our county is...
Date: 10/10/26 10:41 am From: San Mateo County Bird Alliance via groups.io <office...> Subject: Re: [pen-bird] Big Sit.
Hi Susie,
This year we'll be counting in Pescadero Marsh, and due to conditions, we will be setting up on the Butano Creek Trail that is accessible from the parking area along Pescadero Creek Road right after you turn off Hwy 1. If you have any other questions or have issues finding them tomorrow, please contact Nelle Lyons at <1tigger1nl...> or (650) 515-9052.
Date: 10/9/26 7:42 am From: Avis Boutell via groups.io <boutella...> Subject: [pen-bird] Painted Bunting on Pillar Point Bluff
Last night at 5:36 I looked out our kitchen window at birds feeding behind our house and saw a green bird. I took one clear photo before it disappeared into the bushes. It turns out it was an immature or female painted bunting--not a bird normally seen here. From what I read, the bunting's normal range is in south-central and south-eastern United States, wintering in Mexico, Central America, and the Caribbean. I'll post again if I see it again today. Avis
Date: 10/8/26 8:28 pm From: Marty Freeland via groups.io <martinf3...> Subject: [pen-bird] Recent notes: Blackburnian, Magnolia, Prairie, etc.
Hi all,
Highlights from the past four days in San Mateo were an excellent peak fall assortment of eastern warblersBlackburnian, Magnolia, Prairie, Black-and-white, and Palmplus American Redstart, the county's second Painted Redstart, and the continuing invasion of montane birds including numerous Evening Grosbeaks.
On Monday 10/5, I covered the north coast from Mussel Rock to Montara and then skipped to Pescadero to dip on the Prothonotary Warbler found the previous day by Aidan Sinha. The north coast had no standout birds but had decent migrant numbers (e.g., 6 Yellow Warblers at Calera Ck, 5 Warbling Vireos over the course of the morning, etc.) and two Nashville Warblers were together at the Farallone Willows in Montara. Two Nuttall's Woodpeckers together at Pedro Pt were my first there and may (?) mark the southernmost point on the San Mateo coast where they are truly regular, though they are increasing across the board. Arriving at the Prothonotary spot, Jim Lomax and I encountered a group who had just seen the bird and who said encouraging things like "You'll see it." Of course, that meant that we did not see the bird! But a female-type American Redstart was a short distance downstream of where the Protho had been. Aidan Sinha reported a possible American Redstart here the previous day, presumably the same bird.
On Tuesday 10/6, I intended to bird from Weed Farms to San Gregorio. Weed Farms and Pie Ranch were both active with above-average numbers of Western Meadowlark, as has been my experience elsewhere this season too (but pipits seem to be in low numbers in San Mateo, at least). At Costanoa, a dull Palm Warbler was my first at that site and my first this season. Shortly after seeing the Palm Warbler, I put my binoculars on something moving in a willow and saw a Painted Redstart looking back at me. After recovering from being flabbergasted enough to manage some identifiable photos, I sprinted to Costanoa Lodge to get the word out and then spent the rest of the time I had trying to refind the bird with others. Unfortunately I only saw it once after the initial sighting, with Richard Jeffers but before most chasers arrived. Further details, notes, and photos are on eBird.
On the way back to the east side of the mountains for classes in the afternoon, I dodged construction on Hwy 84 by taking Gazos to Cloverdale to Pescadero Ck Rd to Alpine Rd. The next day, Al DeMartini had Pinyon Jays on Alpine Rd. I did not have any Pinyon Jays, but the continuing concentration of Evening Grosbeaks on upper Gazos Ck was an amazing spectacle. All seemed to be Type 1 from the Pacific Northwest, not the call type breeding in the Sierra Nevada. At a location on Gazos with at least 2530 Evening Grosbeaks, I also had two female Pheucticus grosbeaks, one Black-headed and the other perhaps a Rose-breasted (and probably the same possible Rosebeak I had here on 9/29), but they were again uncooperative and I was also distracted by the glorious male Evening Grosbeaks, which were much more interesting. But if anyone wants three "grosbeak" species at once (although Evening is of course a finch and is taxonomically distant from Rose-breasted and Black-headed, despite the shared name), this might be your chance...
On Wednesday 10/7, I covered the south-central coast from Pescadero Ck to Pilarcitos Ck. Pescadero Marsh was blanketed in ground fog so I started instead at the Bianchi property, which has a pumpkin patch and other nice agricultural land (accessed with permission, but the pumpkin patch is open to the public from 105). A calling Evening Grosbeak was west across Cloverdale Rd from the Bianchi farm. Because of the thick low fog all over the immediate coast, I checked willow patches in eastern Pescadero that I sometimes skip. At the end of Goulson St, a beautiful Blackburnian Warbler was high in the cottonwoods, giving buzzy flight calls like a Yellow Warbler, before working its way down into the Pescadero Ck riparian to feed. Halfway down Goulson a flock in a different patch of riparian had a Black-and-white Warbler. Maybe I should not skip these parts of Pescadero! I was excited to see that a new community park will open on the vacant lot where Cdric Duhalde found a Blue Grosbeak a few years ago, offering more access to that chunk of creek. Two Nashville Warblers were at the Ovenbird spot on the west side of town. This is a really great year for Nashvilles; I think these were my sixth and seventh so far this season in the county, while most years by this date I have had 02. Working all the accessible patches on San Gregorio Ck, Tunitas Ck, and their feeder creeks, the only good flocks I located were on Tunitas Ck well upstream. In one of the best flocks along Tunitas, at the dip, there was a nice Magnolia Warbler. The rest of the day was rather slow except for the piece of Pilarcitos Ck near Repetto's pumpkin patch where a waterthrush was a few weeks ago; that spot had a Western Flycatcher, two Yellows, and many other migrants. In general I struggled to find migrants on the immediate coast on this day, with all the concentrations being pretty well inland. All day I had only 5ish Yellows, 1 Western Fly, no Warbling Vireos, no uncommon western migrants besides the Nashvilles in Pescadero and one Black-throated Gray on upper Tunitas, etc.
On Thursday 10/8, I birded from Pillar Point to Miramar in the morning, covering the last chunk of the coast north of Ano that I had not done this week. For the most part it was quite slow. A flock along San Vicente Ck accessed from Ember Ridge had a Warbling Vireo and a Yellow Warbler; another Yellow Warbler was at the Emergency Willows. Checking the East Miramar Willows, a Prairie Warbler was working the low vegetation around the lone alder. This was only my second rarity here, after a Tennessee with Alex Castelein a couple years ago, over about 2530 checks in fall, so it was especially fun to see. I like constructing routes made largely of stops where you can hope for a vagrant roughly once every 1020 visits, but including well more than 20 such sites, so on the whole you still end up (on average) with the odds in your favor.
In addition to all the other irruptive movements documented this year, there has been a modest movement of Golden-crowned Kinglets into the lowlands over the last week, including two at Princeton Willows today. Cassin's Finches have reached SF, Santa Clara, and Santa Cruz, and should certainly be gettable along Skyline in San Mateo this week! And southern Oregon and northern Nevada had reports of Blue Jay in the past few days as well.
An awesome week of peak season in an awesome county! Enjoy the last couple weeks of fall!
Date: 10/7/26 4:23 pm From: Dominik Mosur via groups.io <dominikmosur...> Subject: [pen-bird] 2nd Hand Report of Pinyon Jays 10/7/2026
I just received a phone call from Al DeMartini. This morning, just before sunrise, along Alpine Road near Heritage Grove Al heard and saw a minimum of (18) Pinyon Jays on the move.
First, photos, video, audio, and other details and comments are on eBird: https://ebird.org/checklist/S399897142. A Palm Warbler is also at this spot and others had a Tennessee here later in the day as well.
PLEASE be very mindful about access at this location. The riparian along Whitehouse Ck, where the Painted Redstart was, is the private property of Costanoa Resort. Birders are permitted to access the riparian IF we park in the main parking lot, not in pullouts along the private road, and walk back down to the creek. This was confirmed today by Costanoa management. There is a store and a restaurant at Costanoa Resort that are open to the public and that is why birders can access this site (the management hopes we will make purchases at the restaurant or store), so consider visiting them and buying something if you are here. It is important to keep management favorably disposed toward birders so that we do not lose access to this awesome location. Thanks to Caitlin Chock for helping get access details out while I was trying to send satellite texts from the stakeout with very poor reception.
Some quick additional details about the bird: After I found it just before 9:30, I left to reach cell service and get the word out. After returning and trying to relocate it for an hour, Richard Jeffers and I heard it calling a short distance upstream from the original spot and Richard spotted it in an alder. We got good but brief views before it vanished again into the riparian. I think Tom Duncan may have seen it briefly a couple hours later, but other than that it was not detected again today despite much effort, as far as I know. It disappears into the riparian and (likely) into the stands of tall Eucalyptus and other exotic trees, much of which is more or less inaccessible, and clearly it does not call very often, although it called repeatedly (and spontaneously) for several minutes around 10:30 when it was seen for the second time.
Although it was missed for much of the day today, it is certainly possible that the bird may be present tomorrow (plenty of previous fall migrants in NorCal have stayed multiple days). If you chase, again, please be very careful to park in the main lot and stay out of the way of resort staff and guests.
Good birding,
Marty Freeland
________________________________
From: <peninsula-birding...> <peninsula-birding...> on behalf of Marty Freeland via groups.io <martinf3...>
Sent: Tuesday, October 6, 2026 9:41 AM
To: 'Peninsula Birding' <peninsula-birding...>
Subject: [pen-bird] PAINTED REDSTART
This morning, the adult male Eurasian Wigeon in eclipse plumage was still among American Wigeons at the pump house on the Nob Hill Pond in Redwood Shores. At midday,I did a short skywatch looking for raptors at home in Redwood Shores. There were the expected Turkey Vulture, Red-tailed Hawk and Cooper's Hawk. A nice surprise wasa light-morph adult Swainson's Hawk southbound low overhead. Yesterday in South San Francisco, a Brewer's Sparrow was with several Savannah Sparrows along the SanFrancisco Bay Trail near the footbridge. Access to the trail was from the end of Colma Creek Service Road off of Harbor Way and Littlefield Avenue.
Ron Thorn
Date: 10/5/26 5:38 pm From: San Mateo County Bird Alliance via groups.io <office...> Subject: [pen-bird] Thur. Oct. 8 Endemics w/ Alvaro Jaramillo
*Thursday, October 8, 7:00 pm - Zoom*
*Endemic Birds of the US and Canada - Alvaro Jaramillo*
When birders travel abroad, they are always interested in seeing the “endemic” birds. These are birds that cannot be found elsewhere; they are special to the country or region visited. Even if you are not a world lister, endemics are appealing as they are birds that are specialized to a small sector of the world in many cases. They are sometimes also threatened or endangered. What I find fascinating is that most birders in the US have not asked the question, “What are the endemics of the US?” How about the specialties in Canada? This talk covers these endemics and gives viewers an idea of which birds are truly special in the ABA birding area. Which ones can't be found anywhere else on Earth? *REGISTER:* https://bit.ly/4rtV9IN
*CA Endemic: Yellow-billed Magpie, Photo Credit: Donna Pomeroy*
Date: 10/4/26 7:45 pm From: Aidan Sinha via groups.io <aidansinha...> Subject: [pen-bird] South SM Coast birding today
Hi all,
Today my dad and I headed to the southern San Mateo coast, largely focusing on riparian areas searching for passerines. We started late but were still quite successful!
The major highlights of the day were at least 2 and likely more Evening Grosbeaks at Gazos Creek, a Prothonotary Warbler at Butano Creek in Pescadero, and a Chestnut-sided Warbler at Seaside School Road.
The Evening Grosbeaks at Gazos were initally seen along the road perched up in alders, with at least 2 present here. I later had at least 1 more perched up in a pine well above the road. I suspect many more were present in the area but only confirmed 2 at once. Others later on did have more in the area. It did seem in the cases that I observed the birds that they were moving down the canyon and towards the coast, although I am not sure if a single group moving around was involved or if multiple flocks were passing through the area. This year has seen a large irruption of montane species into California, including nutcrackers, Red-breasted Nuthatches, and others, so Evening Grosbeak is definitely a species to be watching for both at Gazos and elsewhere in the county.
The Prothonotary Warbler was seen initally with a flock along the trail leading along Butano Creek in Pescadero, before soon leaving. I later did see it foraging fairly low around the creek while I was leaving the area. Others were able to relocate it as well later in the day. This spot overall is one of my personal favorites on the south coast, as it was also the site for multiple American Redstarts earlier in the season. I may have briefly had one today as well, though my sighting was brief and I had only poor looks. Overall at Butano birds are fairly low and somewhat closer, though the dense vegetation can make viewing more difficult at times. Still it is a site with high potential and definitely worth a check when visiting the south coast.
The Chestnut-sided Warbler was seen two times in flocks at two separate points along Seaside School Road. This spot is another great site to check on the south coast, with birds being fairly low, easier to view, and usually around fairly late in the day when birding can often be less active.
Besides the rarities the day was still fairly birdy with flocks present at many sites, though nothing else major of note. Many of these flocks had a winter feel to them, being composed mainly of chickadees and Townsend's Warblers. Overall it was a great day out in a very productive area of the coast, definitely an area worth spending time in and an area I will be visiting in the future. Happy fall birding!
Date: 10/4/26 11:23 am From: Peter Metropulos via groups.io <pjmetrop...> Subject: [pen-bird] BLACK & WHITE WARBLER in Colma
Yesterday morning(10/3/26) I spent a couple hours wandering through the tombstones at Cypress Lawn Memorial Park.Most of the bird activity was just east of the mausoleum, mainly consisting of an influx of Yellow-Rumped Warblers,with at least 30 birds present.A BLACK & WHITE WARBLER was crawling up the trunk of an old holly and a NASHVILLE WARBLER was foraging in the canopy of the same tree.Aside from a handful of Townsend's Warblers these were the only migrants I located.
Peter J. Metropulos
Date: 10/1/26 4:49 pm From: Ronald- Thorn via groups.io <Tronthorn...> Subject: [pen-bird] Blackpoll Warbler at the Nob Hill Pond
A Blackpoll Warbler was at the Nob Hill Pond in Redwood Shores. It was associating with other warblers at the northwest corner of the pond. Other migrants were a Western Flycatcher, Ruby-crowned Kinglet, ( 4 ) Northern Yellow Warblers and ( 7 ) Yellow-rumped Warblers. A stop at Coyote Point County Park did not havemuch in a way of migrants. ( 2 ) Chipping Sparrows were among a large group of House Finches.
Ron Thorn
Want more Grosbeak content? Sierra Foothills Audubon has a
spectrogram-rich public talk on Evening Grosbeaks, by UC Davis biologist
Thomas Hahn, on our YouTube channel.
Jul 19, 2025
This public talk – “Evening Grosbeaks of the Sierra Nevada and the West” –
was presented on June 25, 2025, at the monthly meeting of the Sierra
Foothills Audubon Society, in Nevada City, California. About the Talk
Evening Grosbeaks are showy finches of the sub-family Carduelinae—a group
that includes many familiar western songbirds such as goldfinches, house
finches, crossbills, rosy-finches and siskins. Their white, black and gold
plumage makes them stand out at a feeder or along the gravelly side of the
road as you drive into the Sierra. About the Speaker Thomas Hahn, Ph.D., is
a field biologist who has been studying western finches since he was a
graduate student at the University of Washington in the late 1980s and
early 90s. He is a professor at University of California, Davis, in the
Department of Neurology, Physiology and Behavior. His research interests
include environmental regulation of avian annual cycles of behavior,
physiology and morphology, and behavioral and physiological responses of
birds to unpredictable environmental events. He is an authority on avian
communication, especially use of heterospecific mimicry in song, and
learned non-song vocalizations.
Sylvia
YouTube editor for Sierra Foothills Audubon
> *From:* <peninsula-birding...> <peninsula-birding...> *On
> Behalf Of *Alvaro Jaramillo via groups.io
> *Sent:* Wednesday, September 30, 2026 5:19 AM
> *To:* <kforward...>; 'Peninsula Birding' <peninsula-birding...>
> >
> *Subject:* Re: [pen-bird] Evening Grosbeaks at Purisima Creek Redwoods
> OSP 9/29
>
>
>
> Kent
>
>
>
> Looking at the spectrograms, it looks like this is a type 1 Evening
> Grosbeak. You could change the ID to that specifically. This is a
> population from the Pacific Northwest and BC/Alberta. Not the type you have
> in the Cascades/Sierra. This is interesting as it suggests that the
> “montane invasion” birds may be coming from various different places, so
> what is affecting Evening Grosbeaks may not be the same thing as what is
> influencing Pinyon Jays.
>
>
>
> Find out more here:
>
> https://ebird.org/news/evening-grosbeak-call-types-of-north-america >
>
>
> map of types here:
>
>
> https://blog.aba.org/2012/12/five-species-of-evening-grosbeakslets-find-out-together.html >
>
>
> Alvaro Jaramillo
>
> <alvaro...>
>
> www.alvarosadventures.com
>
>
>
> *From:* <peninsula-birding...> <peninsula-birding...> *On
> Behalf Of *Kent Forward via groups.io
> *Sent:* Tuesday, September 29, 2026 11:22 PM
> *To:* Peninsula Birding <peninsula-birding...>
> *Subject:* [pen-bird] Evening Grosbeaks at Purisima Creek Redwoods OSP
> 9/29
>
>
>
> Today while birding the riparian area of lower Purisima I heard Evening
> Grosbeaks! I wasn't able to obtain a visual. I have been studying the
> vocalizations of some of the rarer birds partaking in the current large
> irruption of montane birds to our area so when I heard these vocalizations
> it reminded me of Evening Grosbeak, so I got Merlin going and it concurred,
> and also I got feedback from several skilled ear-birders in the affirmative
> for Evening Grosbeak! This was in the lower parking lot at 37.437585,
> -122.370610
>
>
>
> https://ebird.org/checklist/S397598170 >
>
>
> Happy migration and montane irruption birding!
>
> Kent Forward
>
> El Granada
>
>
Date: 10/1/26 11:38 am From: john tsortos via groups.io <jtsortos99...> Subject: [pen-bird] Pacific Wren, Pacific Shores
Hello all,
I found a Pacific Wren outside my office this morning along Westpoint
Slough. It was seen hopping around in the wind tunnel between two buildings
at these coordinates:
(37.5139981, -122.1995605)
I’ve never seen a Pacific Wren out here, so this was a nice surprise.
Date: 10/1/26 11:27 am From: pauldonahue9 via groups.io <charadrius1...> Subject: [pen-bird] Pillar Point
Dear birders,
After seeing an eBird checklist from September 28th, Teresa Wood and I went down to Pillar Point yesterday morning to look for the Lark Bunting and White-winged Dove. We missed both of those birds, but when we walked down to the edge of the harbor for a look, we saw a suspicious-looking backlit small gull on the water very close to shore. When we got closer, I realized it was a juvenile Sabine’s Gull, a bird I had not realized was being reported there. An injured/sick male Surf Scoter was also along the beach nearby.
I then had the all too common Pillar Point birding experience. While I was photographing the gull, a dog and off-leash dog owner approached from the east. The dog, repeatedly charging into the water, flushed the gull far out into the harbor. At the same time, two more dogs and their off-leash owner approached from the west. Those dogs charged the scoter, driving it into the water, then, joined by the first dog, all three jumped into the water and swam after the duck, driving it farther out into the harbor.
As with the last time at Pillar Point that I saw dogs chasing birds, I had very nasty words with both off-leash owners - an extremely unpleasant experience. There are lots of birds at Pillar Point, and lots of rarities show up there, but I’m afraid it’s going to have to be a very rare bird to get me back to the place.
from Google AI
Dog leash laws apply everywhere throughout Pillar Point Harbor and its surrounding property, parking lots, and nearby coastal bluffs.
Key Harbor Leash Regulations
Mandatory Leashes: San Mateo County and the harbor area require dogs to be securely leashed at all times. There are no designated off-leash zones or voice-control areas within the harbor or at adjacent
Wildlife and Environmental Protection: Because the harbor and adjacent coastline function as a sensitive marine sanctuary protecting nesting seabirds and local wildlife, off-leash violations or wildlife harassment carry severe penalties and fines up to $10,000
Leash Length: Leashes must generally be restricted to a maximum length of 6 feet (and 4 feet or less if visiting or parked in specific zones like the harbor's RV park areas).
Clean-Up Rules: Owners must clean up and bag all pet waste, disposing of it promptly in provided garbage bins.
Paul Donahue
959 Anza Drive
Pacifica, California 94044 USA
(650) 738-0429
<charadrius1...>
Date: 10/1/26 10:17 am From: Marty Freeland via groups.io <martinf3...> Subject: [pen-bird] Recent notes: Prairie, Blackpoll, Magnolia, etc.
Hi all,
Highlights from coverage of the San Mateo coast on Sunday, Tuesday, and Wednesday in peak fall included a great assortment of eastern passerines. There was one each of Prairie, Magnolia, Chestnut-sided, Tennessee, and Blackpoll warblers, plus Northern Parula, plus a Red-eyed Vireo. The inflection points in the Yellow/Townsend's and Swainson's/Hermit ratios both passed between 9/24 and 9/28 or so, about on schedule.
On Sunday 9/27 I started at Ano Nuevo with Chris Henry, Michael Long, Kaiting Huang, and Tino Castillo before birding Santa Cruz for the rest of the day. We had a highish overcast and light NW winds. A Prairie Warbler was at Ano Nuevo in pines not far from the elephant seal entry kiosk, perhaps the first record for Ano other than an old wintering (CBC) record for the flower farm? Although numbers of Yellow Warbler were down by 80% from the previous week, we still had a decent assortment of western migrants, including a female Black-throated Gray Warbler.
(We then spent the next nine hours in Santa Cruz County without any vagrants, because Santa Cruz is not nearly as awesome a county as San Mateo is.)
On Tuesday 9/29 I covered the south coast from Pie Ranch to San Gregorio. It was sunny for most of the day with moderate NW winds becoming quite strong by around 3 pm. A Cackling Goose was with Canadas at the mouth of Gazos Ck in the early morning; it may be an earlyish arrival (folks in HMB had flyover flocks on the same day) or it may be the individual that summered in northern Santa Cruz Co., at Waddell and elsewhere, and that was reported at least once or twice in southern San Mateo. A Red-breasted Sapsucker at Pie Ranch had a very bright whitish bridle and may have had some Red-naped ancestry, but was not (I don't think) an F1 hybrid. On Gazos Ck Rd, a flock around a half-mile up the road had a HY Red-eyed Vireo, the third I have seen this year in the county, and another flock around where last year's Canada Warbler was included a Rose-breasted/Black-headed grosbeak. My views were mostly dorsal and it may have been either, although its maxilla was light pink and in brief looks at the underside it appeared perhaps more consistent with Rose-breasted to me. Checking the bottlebrushes in Pescadero at the junction of Pescadero Ck Rd and Butano Ck Cutoff, I heard a "half a Yellow Warbler chip" (Ethan Monk's apt term for the category of chip like a Yellow, but cleaner and less husky, that a number of eastern warblers fall into) and pished out a male Northern Parula. At Water Lane, a Nashville Warbler was with a large flock. I had Warbling Vireos at 9 spots with a total of at least 16 individuals, perhaps more, and remarkably only one Wilson's Warbler (at the Butano Ck bridge).
On Wednesday 9/30 I birded the central coast from Pescadero Marsh to Montara with light NW wind and clear skies until a low marine layer rolled in around 4 PM. The ardeid show at North Pond in Pescadero Marsh continues to be impressive, with 30+ Great Egrets and 20+ each of Great Blue Herons and Snowy Egrets. Seems like a great setup for San Mateo's first Tricolored Heron or similar! A Nashville Warbler was at the dip on Tunitas Creek Road. Stopping at various creek accesses (Church St, Johnston St, Main St, Mariners Church, Oak Ave, etc) in Half Moon Bay around noon, I found a large flock behind the Mariners Church and had Magnolia and Chestnut-sided warblers in the flock in quick succession. A double-vagrant flock is always an awesome experience and this one was especially so, as I had gone the whole morning of arguably the very peak date of fall without a vagrant and these were my first good birds at this patch after a year or so of checks. At Sweetwood CG, a Tennessee Warbler was high in the Eucalyptus. Checking Princeton Willows as low afternoon fog was rolling in, I could not locate any flocks but heard another eastern-type chip and tracked down the calling bird, which was a bright Blackpoll Warbler, for excellent views. I think that puts the county at 3 Blackpolls to 4 Blackburnians so far this fall. At the Farallone Willows in Montara, there was another Nashville Warbler. This species is also having a strong showing this fall on the coast. I had only 6 Warbling Vireos on this day and had 3 Wilson's Warblers. Numbers of Orange-crowned Warbler and Western Flycatcher were very strong on both days.
Details, coordinates, photos, etc., are on eBird as always.
There has been a superbly well documented move of Clark’s Nutcrackers to areas where they are not regularly found, including the central coast. But also as far east as Minnesota, check out eBird and restrict to Aug-Nov for current year to see the extent of records.
Looking at the spectrograms, it looks like this is a type 1 Evening Grosbeak. You could change the ID to that specifically. This is a population from the Pacific Northwest and BC/Alberta. Not the type you have in the Cascades/Sierra. This is interesting as it suggests that the “montane invasion” birds may be coming from various different places, so what is affecting Evening Grosbeaks may not be the same thing as what is influencing Pinyon Jays.
From: <peninsula-birding...> <mailto:<peninsula-birding...> <peninsula-birding...> <mailto:<peninsula-birding...> > On Behalf Of Kent Forward via groups.io
Sent: Tuesday, September 29, 2026 11:22 PM
To: Peninsula Birding <peninsula-birding...> <mailto:<peninsula-birding...> >
Subject: [pen-bird] Evening Grosbeaks at Purisima Creek Redwoods OSP 9/29
Today while birding the riparian area of lower Purisima I heard Evening Grosbeaks! I wasn't able to obtain a visual. I have been studying the vocalizations of some of the rarer birds partaking in the current large irruption of montane birds to our area so when I heard these vocalizations it reminded me of Evening Grosbeak, so I got Merlin going and it concurred, and also I got feedback from several skilled ear-birders in the affirmative for Evening Grosbeak! This was in the lower parking lot at 37.437585, -122.370610
Date: 9/30/26 2:52 pm From: Kent Forward via groups.io <kforward...> Subject: Re: [pen-bird] Crystal Springs and Año Nuevo CBCs
Hi Chris! I can only do Crystal Springs CBC this year. I ran into Marj the other day and we were wondering if her, Ryan and myself could do Rancho again?Thanks!Kent
On Wednesday, September 30, 2026, 1:45 PM, Chris M. via groups.io <chrismac...> wrote:
Hi Birders,
I’m writing to invite you to participate this year in eitheror both of San Mateo County’s CBCs
Crystal Springs CBC - Saturday, December 19, 2026
Año Nuevo CBC - Saturday, January 2, 2027
All CBCs are a citizen-science endeavor with the primarygoal of counting all individuals of each species of bird detected in a 10mile diameter circle on a single day.
The Crystal Springs count circle stretches from theBay to the Coast and from Burlingame in the north to Redwood City inthe south. Año Nuevo includes the coast and up to Sam McDonald Park andfrom a piece of Big Basin to San Gregorio Road. The counts include alltypes of habitats and terrain - some require lots of hiking, some coverareas with lots of redwoods but few birds, some mean you have to know yourshorebirds well, some are flat, some strenuous, some urban, with most openspace - there is something for everyone.
I’d like to invite you to participate this year. We need alllevels of experience, from beginners willing to be tabulators and spotters, tothose of you with experience, whether you have counted with us in the past ornot.
We will soon have a signup form on the San Mateo County BirdAlliance website: https://smcbirdalliance.org/CBC.html. Please sign up on this form as it’smore reliable than an email I might misplace.
However, if you have already contacted me, there’s no needto sign up again. Check the website in the next few days.
If you want more information, please feel free tocontact me directly at <cbc...>
Date: 9/30/26 12:45 pm From: Chris M. via groups.io <chrismac...> Subject: [pen-bird] Crystal Springs and Año Nuevo CBCs
Hi Birders,
I’m writing to invite you to participate this year in either or both of San
Mateo County’s CBCs
*Crystal Springs CBC - Saturday, December 19, 2026*
*Año Nuevo CBC - Saturday, January 2, 2027*
All CBCs are a citizen-science endeavor with the primary goal of counting
all individuals of each species of bird detected in a 10 mile diameter
circle on a single day.
The *Crystal Springs *count circle stretches from the Bay to the Coast and
from Burlingame in the north to Redwood City in the south. *Año Nuevo*
includes the coast and up to Sam McDonald Park and from a piece of Big
Basin to San Gregorio Road. The counts include all types of habitats and
terrain - some require lots of hiking, some cover areas with lots of
redwoods but few birds, some mean you have to know your shorebirds well,
some are flat, some strenuous, some urban, with most open space - there is
something for everyone.
I’d like to invite you to participate this year. We need all levels of
experience, from beginners willing to be tabulators and spotters, to those
of you with experience, whether you have counted with us in the past or
not.
Date: 9/30/26 11:53 am From: Ronald- Thorn via groups.io <Tronthorn...> Subject: [pen-bird] Clay-colored Sparrow at the Nob Hill Pond
This morning, there was a Clay-colored Sparrow at the Nob Hill Pond in Redwood Shores. It was foraging on the ground among the low Sweet Fennel along the publicaccess trail just past the corner house. It was flushed a number of times, and did fly off towards the direction of the pump house. There were ( 5 ) Blue-winged Tealand a record high number for the pond ( 43 ) Cinnamon Teal. Some of the Cinnamon Teal were along Phelps Slough. Early this morning during a skywatch from home in Redwood Shores, a group of ( 41 ) Vaux's Swifts were southbound. There has not been much in the diversity of migrants along the bayside. Orange-crowned andWilson's Warblers have been way below average. Where the opposite, Western Flycatcher has been way above average. Coming in second place has been ChippingSparrow.
Ron Thorn
Date: 9/30/26 5:18 am From: Alvaro Jaramillo via groups.io <chucao...> Subject: Re: [pen-bird] Evening Grosbeaks at Purisima Creek Redwoods OSP 9/29
Kent
Looking at the spectrograms, it looks like this is a type 1 Evening Grosbeak. You could change the ID to that specifically. This is a population from the Pacific Northwest and BC/Alberta. Not the type you have in the Cascades/Sierra. This is interesting as it suggests that the “montane invasion” birds may be coming from various different places, so what is affecting Evening Grosbeaks may not be the same thing as what is influencing Pinyon Jays.
From: <peninsula-birding...> <peninsula-birding...> On Behalf Of Kent Forward via groups.io
Sent: Tuesday, September 29, 2026 11:22 PM
To: Peninsula Birding <peninsula-birding...>
Subject: [pen-bird] Evening Grosbeaks at Purisima Creek Redwoods OSP 9/29
Today while birding the riparian area of lower Purisima I heard Evening Grosbeaks! I wasn't able to obtain a visual. I have been studying the vocalizations of some of the rarer birds partaking in the current large irruption of montane birds to our area so when I heard these vocalizations it reminded me of Evening Grosbeak, so I got Merlin going and it concurred, and also I got feedback from several skilled ear-birders in the affirmative for Evening Grosbeak! This was in the lower parking lot at 37.437585, -122.370610
Date: 9/29/26 8:21 pm From: Kent Forward via groups.io <kforward...> Subject: [pen-bird] Evening Grosbeaks at Purisima Creek Redwoods OSP 9/29
Today while birding the riparian area of lower Purisima I heard Evening Grosbeaks! I wasn't able to obtain a visual. I have been studying the vocalizations of some of the rarer birds partaking in the current large irruption of montane birds to our area so when I heard these vocalizations it reminded me of Evening Grosbeak, so I got Merlin going and it concurred, and also I got feedback from several skilled ear-birders in the affirmative for Evening Grosbeak! This was in the lower parking lot at 37.437585, -122.370610
Date: 9/28/26 2:58 pm From: Ronald- Thorn via groups.io <Tronthorn...> Subject: [pen-bird] Eurasian Wigeon, Common Tern
This morning at the Nob Hill Pond in Redwood Shores, there was a male Eurasian Wigeon in eclipse plumage. Maybe a returning one? Arrival last fall on the pond wasSeptember 10th. Yesterday, Leonie and I noted a Common Tern among Forster's Terns on the bay mudflats off the mouth of Colma Creek in South San Francisco.
Ron Thorn, Leonie Batkin
Date: 9/26/26 5:03 pm From: lebeck777 via groups.io <lebeck777...> Subject: Re: [pen-bird] Yellow-bellied Sapsucker at Wunderlich Park?
I revisited my location from two days ago. It is on the Bear Gulch trail at approximate GPS location 37.410384, -122.264329. Looking downslope from there today, I saw at least three trees with sapsucker holes. From which bird and how recently, I can't say. I didn't see any woodpeckers today, but the trails are much busier on weekends, so I will try again next week. The area between this trail location and the stable is the area where I saw the bird.
A red-breasted sapsucker would be more likely, I know...
