Yolo Notable Sightings: September 2023

The month of September is famous in the birding world for its impressive migration and the potential to bring rare birds to unexpected places. September 2023 was no exception, as a slew of rarities kept Yolo County birders busy throughout the month.
   The indisputable highlight was a stunning BLUE-HEADED VIREO photographed at the Putah Creek Riparian Reserve on 9/11 (JG). This eastern vireo is very rare in California and was well documented before it flew across the creek and out of sight to the south. Blue-headed and Cassin’s Vireos are infamously difficult to tell apart, but the excellent photos of this bright and contrasty individual were unanimously agreed upon to represent the first record for both Yolo and Solano Counties.
   When it comes to fall migration, the warblers often steal the show. Picking through flocks of neotropical migrants produced an impressive list of “vagrants,” or lost eastern birds that turn up out of place. This month, three NORTHERN PARULAS were observed. An adult female at the Putah Creek Riparian Reserve continued from August and was seen well into September. A second parula was found at Elk Slough near Clarksburg on 9/2 (AE). The third individual was seen briefly at the Putah Creek Riparian Reserve on 9/3 (JG), almost a mile from where the other bird was being reported. Prior to this fall, it had been three years since Yolo had hosted a NORTHERN PARULA. Along with the trio of parulas came three separate AMERICAN REDSTARTS in the county. One was at Putah Creek Riparian Reserve on 9/1 (SaS), a stunning male was discovered at Babel Slough on 9/2 (KT, MG), and another was found in a north Davis backyard on 9/19 (CD). Amazingly, this brings the total to four AMERICAN REDSTARTS in Yolo County this year, following a singing bird in June. Keeping with the rare warblers, a NORTHERN WATERTHRUSH was found and photographed at the Yolo Bypass Wildlife Area on 9/9 (JG).
    Along with the warblers came a few exciting sparrows. A LARK BUNTING at the Yolo Bypass Wildlife Area on 9/8 was a big surprise, and was a county bird for many who chased it that day (JE). A BREWER’S SPARROW at the Sacramento Bypass was an exciting find on 9/14 (KD), and was the first chaseable individual of the species in a few years. More expected were multiple reports of GREEN-TAILED TOWHEES in the county. One was at Putah Creek Fishing Access #1 on 9/5 (SeS), two were found at Grasslands Regional Park on 9/11 (KD, MP, SoS, JH), and another was reported from Cache Creek Canyon on 9/28 (TP). A migrant VESPER SPARROW discovered along County Road 155 on 9/23 is a noteworthy record for a species that can be quite difficult in the county (KS).
   Shorebirds continued their migration through the county and the County Road 104 ponds proved to be the best habitat. On 9/7, a STILT SANDPIPER was discovered (MH, FF, ZP, KF). It was seen off and on for about a week. Two weeks later, on 9/23, an AMERICAN GOLDEN-PLOVER was photographed briefly before being flushed by a Peregrine Falcon, never to be seen again (ZP, BW). Prior to this bird it had been three years since Yolo’s last American Golden-Plover. While searching through waterbirds, two early EURASIAN WIGEON were found. One male in eclipse plumage at Woodland WTP on 9/21 sets the record for the earliest arrival date in the county (ZP, BW), and another was photographed at the County Road 104 ponds on 9/24 (ZP).
   On 9/23, a CHESTNUT-BACKED CHICKADEE, the first in the county in three years, was found at County Road 41 in the Capay Valley (ES). Chickadees have become very hard to find in the county in recent years. Bringing the month to a close, an adult “THAYER’S” ICELAND GULL was photographed at the County Road 104 Ponds on 9/30 (KD, LW, CT). This represents one of the earliest fall return dates for the species, which usually does not arrive until late October.

Thanks to the following for their reports:
Andrew Engilis (AE), Bart Wickel (BW), Cameron Tescher (CT), Chris Dunford (CD), Elliot Schoenig (ES), Frank Fabbro (FF), John Hansen (JH), Jonathan Eisen (JE), Joshua Greenfield (JG), Ken Ferguson (KF), Kim Tenggardjaja (KT), Kirk Swenson (KS), Konshau Duman (KD), Lynette Williams (LW), Marcel Holyoak (MH), Michael Perrone (MP), Mike Guard (MG), Samuel Schmidt (SaS), Sean Smith (SeS), Sonjia Shelly (SoS), Tom Pritchard (TP), Zane Pickus (ZP)

–Zane Pickus