Date: 6/3/25 9:58 pm From: Zane Pickus via groups.io <zanep987...> Subject: [centralvalleybirds] Late Spring Migrants— observations in Yolo County
Hi Birders,
There has been much discussion amongst birders throughout California about
how late spring migration has been this year. This certainly was noticeable
in the Central Valley. While some have noted the slow start to spring and
the relatively poor showing of migrants in April, things seemed to pick up
in May. Now we have reached what is typically the tail end of migration,
and yet I continue to see exciting numbers of migrants for the late date. I
felt it worthy to report the following observations of notably-late
migrants that I have both personally observed and seen reported in the past
week in Yolo County.
Hermit Warblers: Prior to this week there were no June records of this
species for Yolo County. Julian Johnson observed one yesterday at the Putah
Creek Riparian Reserve for a new late spring record. That record was
quickly broken this morning when Julian and I had a singing male in a
riparian patch at the Yolo Bypass Wildlife Area (YBWA). I see that Sean
Smith also reported a female Hermit in Davis today on eBird. Perhaps more
will be found in the coming days. There are very few June records for the
Central Valley overall.
Townsend’s Warblers: Usually gone by the last week of May, I have observed
Townsend’s Warblers at nearly every passerine birding stop I have made in
the past week, including three individuals this morning in random willow
riparian patches at the YBWA. Others have observed additional Townsend’s
Warblers in the county in the past week along Putah Creek and elsewhere.
Black-throated Gray Warbler: Sean, Julian, and I had a female at the Cache
Creek Settling Basin on 6/1. There are just a small handful of June records
for the county.
Western Sandpiper: A healthy-appearing adult was photographed at the YBWA
on 5/31 by Joo Tan, which looks to be the latest spring record for the
county.
Purple Finch: Not known to nest in the county, Joshua Greenfield reported
two birds, including a singing male, on Rayhouse Road in the Coast Ranges
on 5/29. These could either represent the latest spring migrants or a
potential first breeding record for Yolo County.
Migrants of other various other species that tend to straggle into June
(Willow Flycatcher, Western Wood-Pewee, Western Tanager, Swainson’s Thrush,
and Black-headed Grosbeak, to name a few), all continue to be reported in
Yolo County daily. One intriguing theory for the late spring is how mild
the temperatures have been for the time of year. In Yolo, we have only
reached temperatures of 100F for two days (last weekend), far below the run
of hot weather that usually occurs by June in the valley. Perhaps there are
other factors at play as well, but the lack of hot days to get birds moving
north may well be playing a role in migrants passing through later than
expected.
Regardless, spring migration is still very much underway and I encourage
everyone to get out and see what you can turn up in your local patches!
