Date: 10/6/25 12:40 pm From: Zac Denning via groups.io <zdenning1...> Subject: Re: [SFBirds] Diurnal migration now (Monday)
Thanks for the nice report, Liam!
Similarly, in the east bay yesterday morning, Bruce Mast and I observed
significant numbers of Vaux’s Swifts (73) and Violet-Green Swallows
(108) moving
past Vollmer Peak, counted individually. At times, the flow was heavy
enough to make accurate counts a challenge - and I’m sure many more were
moving out of our immediate view.
Also obviously on the move, were Northern Flickers (19, almost certainly an
undercount) and to a lesser extent (mostly from my later solo peak
watch), Sharp-shinned Hawks (5, from several locations). The flickers were
mostly migrating lower down through the valleys and lower slopes, so were
harder to detect, though we heard them constantly. Migrating Hermit
Thrushes were also in abundance, and Red-breasted and Pygmy Nuthatches were
present in very strong numbers (but difficult to observe movement through
trees without more focused effort). A lone Swainson’s Thrush and 4 Brewer’s
Blackbirds were also in the mix.
Very early on, a small portion of the Vaux’s movement was southward, but
after that, all the
Vaux’s & Violet-greens were moving north. My guess is that the southbound
Vaux’s at least, were already-arrived wintering birds on daily foray from
the McNeer Brickyard roost spot (to the north, in San Rafael, Marin Co),
while the northbound Vaux’s were still on their way to winter roof spots at
McNear, the Healdsburg roost, or further north. The northbound direction of
Violet Green swallows at that one moment may be related to wind direction
and topography in that particular spot, as one leg of a generally
southbound migration. But who knows? The Vaux’s and Violet-Greens were
often in loosely segregated or slightly mixed groups.
Zac
On Mon, Oct 6, 2025 at 12:00 PM Liam Murphy via groups.io <liammsf=
<gmail.com...> wrote:
> Impressive numbers of Vauxs Swifts and Violet green Swallows flying by
> Bernal Hill right now on a warm east wind. I encourage you to take your
> lunch hour outside and see what can be seen.
>
> Cheers,
> Liam Murphy
>
>
>
