Date: 5/5/25 4:30 pm From: Bruce Mast via groups.io <cathrasher4...> Subject: Re: [EBB-Sightings] Mount Diablo Big Day Hike results
Thank you Ethan! I appreciate your detailed insights from the data. I
haven't been tracking incidence of unsuccessful sparrow searches since
April 12 so that would certainly be evidence in favor of the one-day-wonder
hypothesis. On the flip side, it strikes me as a remarkable coincidence
that two one-day-wonders would both show up within 3 weeks of each other in
the exact same patch of chamise. It will be interesting to see whether
people continue to detect this bird for any length of time.
More generally, it would be gratifying to have breeding Black-chinned
Sparrows in the East Bay again. I read Grinnell's reports about
Black-Chinned breeding in places like Claremont Canyon and wonder what it
would take to bring them back. I suspect a change in fire management
practices would be required.
Bruce
On Mon, May 5, 2025 at 2:42 PM Ethan Monk <z.querula...> wrote:
> Hi Bruce,
>
> Thanks for the report! The Black-chinned Sparrow is very cool, but I would
> not be so quick to consider it the same bird Sam Talarigo found on April
> 12th. The recent pattern of sightings in the county is that early sightings
> seem to mostly (all?) represent one-day-or-less wonders, with the
> long-staying birds since 2010 (I count four?) all being found in the second
> half of May or June. One day wonders (5-6ish?) all being between April 12
> and May 12th ?
>
> There are several examples just outside of the county of long-staying
> birds that have shown up earlier, but all a roundabout way of saying that
> there is a track record of early season Black-chinned Sparrows disappearing
> quickly, so I wouldn't necessarily consider it a given that this bird is
> continuing. Especially since I gather people looked for Sam's bird after he
> found it.
>
> Ethan Monk
>
> On Mon, May 5, 2025 at 9:48 AM Bruce Mast via groups.io <cathrasher4=
> <gmail.com...> wrote:
>
>> Good morning birders,
>> Yesterday I completed my second annual Mount Diablo Big Day Hike for
>> Golden Gate Bird Alliance Birdathon. My hike started in Mitchell Canyon at
>> 4 am and ended at the Castle Rock Parking lot at 6 pm. I tallied 78 species
>> total, compared to 72 in 2024. Total hike was 14.6 miles, with a net
>> elevation change: 2150 ft up, 2425 ft down. Special thanks to my wife
>> Juliet, who shuttled me to and from my start and end points.
>>
>> Highlights
>> • 3 owl species (Great-horned, Western Screech, and American Barn), plus
>> Common Poorwill before dawn
>> • Continuing Black-chinned Sparrow, first reported by Sam Talarigo on
>> April 12
>> • At least 1, probably several lingering Calliope Hummingbirds
>> • One Golden Eagle soaring over Eagle Peak
>> • 8 different Cooper’s Hawks throughout the day
>>
>> New additions compared to 2024 results
>> • Wild Turkey—Pine Canyon
>> • Sharp-shinned Hawk
>> • Red-shouldered Hawk—Castle Rocks picnic area
>> • Barn Owl
>> • Western Screech-Owl
>> • Peregrine Falcon—Castle Rocks breeding pair
>> • Western Wood-Pewee—calling from the ravine below Angel Kerley Road. Not
>> where I would have expected it!
>> • American Crow—distant caws at dawn
>> • Phainopepla—Pine Pond. Not where I would have expected it!
>> • Lawrence's Goldfinch—multiple locations
>> • Black-chinned Sparrow—stakeout
>> • Western Meadowlark—grassland pastures above Stage Road
>> • MacGillivray's Warbler
>> • Yellow Warbler
>> • Western Tanager
>>
>> Missed species from 2024
>> • White-tailed Kite—Margot reported it earlier in the morning but I
>> couldn’t refind it
>> • Hammond's Flycatcher
>> • Brown Creeper—surprising bird last year
>> • Northern Mockingbird—surprising bird last year
>> • White-crowned Sparrow—getting late
>> • Golden-crowned Sparrow—getting late
>> • Bullock's Oriole—not at Pine Pond this year
>> • Nashville Warbler
>> • Black-throated Gray Warbler
>>
>> Other birds reported the same day at Mitchell Canyon that I missed:
>> Northern Harrier, Rock Wren, White-tailed Kite, and Rufous Hummingbird. A
>> few people reported some surprising species that could use some
>> documentation: Black-chinned Hummingbird, Chipping Sparrow, and Hermit
>> Thrush.
>>
>> Full trip report with eBird checklists and detailed narrative at
>> https://ebird.org/tripreport/361499 >>
>> Bird on,
>>
>> Bruce Mast
>> Oakland
>>
>>
>>
>>
>>
