Scarlet Tanager ©John Sterling

The past four months have been phenomenal for rare birds in Yolo County, including some of the rarest finds in county history. Since the beginning of May, Yolo County has added three new species to its all-time bird list, and has hosted a variety of other rarities including a total of seven eastern vagrant songbirds! These rarities have appeared in all corners of the county and kept local birders happy throughout the spring, summer, and early fall. Buckle up – the following Yolo County summer birding highlight reel is one of the flashiest in recent memory!
   On 5/7, a thrilling adult male BLUE-WINGED WARBLER was discovered in North Davis (LD). This thrilling warbler of the eastern forests was the first new species added to the Yolo County bird list in 2026, and was observed by dozens of birders as it foraged and sang from the trees along the greenbelt. The bird was seen only briefly on the next morning before it disappeared, but not before it had made headlines throughout the region. This is just the second Central Valley record, with the previous from Sacramento County in May 2008.
   Yolo County had another first county record on 6/6, in the form of a stunning male SCARLET TANAGER at a private residence in Guinda (ES). This epic rarity was also seen by dozens of birders throughout its one-day visit, garnering plenty of “oohs” and “ahhs” from a constant crowd of happy birders enjoying the beautiful vagrant. The bird had a particular affinity for a small plum tree in the yard, feasting on fruit between visits to a shady tree to escape the 100+ degree weather.
   In this day and age, first Yolo County records are often separated by months or even years. Such was not the case in June, as on 6/12 an adult LAUGHING GULL was photographed at the Yolo Bypass Wildlife Area (YBWA) for the first county record of 2026 (JE). The bird was only observed by two birders on 6/12 before it disappeared, and after a thorough search everyone expected it was gone for good. After all, nearly every prior LAUGHING GULL record from inland northern California involved one-day-wonders. However, what was almost certainly the same bird was discovered on 8/2 in the same area, this time amongst a growing flock of migrant RING-BILLED and CALIFORNIA GULLS (ZP). The LAUGHING GULL would be seen off and on here for the next few weeks, oftentimes appearing late in the evening to roost with other gulls. It seemed that most of the gulls at the bypass commuted daily to the UC Davis Primate Center to eat during the day, apparently with the intention of feasting themselves on “monkey chow” to their hearts’ content! Therefore it was not a huge surprise when the LAUGHING GULL was rediscovered once more near the Primate Center in the afternoon of 8/21 (PB). What was surprising was the bird finding a new home at the Woodland Wastewater Treatment Plant (WWTP) on 8/28, and continuing there through the month (ZP, BW). Now this wayward gull has been in the county for nearly three months and shows no sign of leaving. Where will it show up next?
   In addition to first county records, Yolo had an additional five songbird vagrants this summer, perhaps a record number. The most shocking of these was a male BLACK-THROATED BLUE WARBLER at Babel Slough on 8/30 (JG). One of the most popular eastern warblers, and highly unlikely to make it to the Central Valley, this furtive adult male played hide-and-seek through the end of the month. Its deep blue back suggests it is an adult male of the northern (Canadian and northeastern U.S.) breeding population, rather than a stray from Appalachian mountains. It is the first chasable Yolo County record, and third overall, following single-observer reports from Putah Creek Canyon in 2010 and Davis in 1980. Birders chasing the BLACK-THROATED BLUE WARBLER were delighted to also find an adult NORTHERN PARULA on the same dates, which came right on the heels of multiple parulas in nearby Solano and Sacramento counties in the same week (MS).
   Working in reverse chronological order, a male INDIGO BUNTING, in brilliant blue attire, was found singing as though on territory in the Cache Creek Settling Basin on 7/20 (KD). The bird was observed off and on for about two weeks. One has to wonder when this bird may have arrived in the area. Perhaps it summered somewhere locally.
   Backing up to spring migration, a male HOODED WARBLER was singing along Putah Creek east of Winters on 6/10 (ZP). Just the fourth Yolo County record and the first for neighboring Solano County, the bird was discovered on private property during a formal biomonitoring survey and was not chasable. This was the first HOODED WARBLER in Yolo County since 2018. A singing male AMERICAN REDSTART was found along a private stretch of the YBWA on 5/10 (BW). Although a semi-regular rarity in the fall, there is only one prior spring record of AMERICAN REDSTART for Yolo. Both of these warblers were only present for one day.
   Other spring migrant notables included a DUSKY FLYCATCHER at Babel Slough on 5/7 (JG), as well as a migrant PURPLE MARTIN along the Blue Ridge on 5/16 (KS). Interesting fall migrant shorebirds include a pair of SNOWY PLOVERS at WWTP on 7/22 (JG, KO), and an early juvenile PECTORAL SANDPIPER at the YBWA on 8/12 (ZP). There have been two reports of GREEN-TAILED TOWHEES this August: one was at South Fork Putah Creek Preserve on 8/21 (KD) and the other was at Babel Slough on 8/30 (JG).
   Finally, it is worth time to think ahead to the coming months. September is often considered the best birding month of the year in Yolo County, with migrants of nearly all species on the move and birds dispersing all over the place. Now is a great time to get out and look for migrant warblers, tanagers, vireos, flycatchers, etc. In addition to this, it is shaping up to be a great fall for RED-BREASTED NUTHATCHES, with dozens of reports already in August potentially indicating a large irruption winter for the species. Local birders that have started birding in recent years or just moved to the region will be in for a treat; we have not had a full-scale irruption winter of this species since 2023.

California Bird Atlas Updates – Yolo County:

Summer saw a period of continued growth of the California Bird Atlas (CBA), with peak nesting season in summer encouraging birders to submit their data to the statewide project. Statewide, over 50,000 observers have now submitted data to the atlas, across nearly 200,000 atlas eBird checklists, and confirming 318 species as having nested in California this year. These incredible statistics will only continue to grow over the next four years of the atlas. For more information on statewide atlas statistics, check out the portal here.
   Yolo County continues to grow its data contributions to the CBA, with over 2,500 individual checklists submitted in the county through the month of August. 341 birders have now contributed breeding bird observations in Yolo, nearly double the number from the end of April! This increase in participation is encouraging and critical to the success of the CBA in Yolo County and beyond. At this point, 86/101 Atlas Blocks have data, though all are far from the requirements to be considered “complete” blocks. In other words, all data is welcomed! 115 species have been “Confirmed” as breeding in the county so far, a huge increase since the end of April. Now that the breeding season is mostly over for 2026, let’s take a closer look at a few notable breeding statistics from this summer:
 

• The species with the most breeding confirmations in Yolo County through August is the WESTERN KINGBIRD, with 30 “confirmed” breeding records to date. EUROPEAN STARLING (28), CLIFF SWALLOW (26), and BUSHTIT (25) are all close behind.
• A NORTHERN YELLOW WARBLER was confirmed breeding at Cache Creek Settling Basin in July (KD). This species has been slowly returning as a breeder in the Sacramento Valley after being nearly extirpated in the previous century. https://ebird.org/atlascalifornia/checklist/S374474272
• While likely a regular breeder in difficult-to-access locations in the southern Yolo Bypass and Capay Valley, GRASSHOPPER SPARROW was a notable confirmation off County Road 105 in June (KD, KS). https://ebird.org/atlascalifornia/checklist/S356902024
• LEAST BITTERNS are scarce and secretive nesters in Yolo County that can be difficult to confirm for the atlas. A pair of recently fledged young at a private wetland near Dunnigan was the first confirmed breeding in the county for the atlas (ES). https://ebird.org/atlascalifornia/checklist/S374874147
• A family group of MOUNTAIN QUAIL on County Road 53 west of Brooks was the first Yolo County breeding confirmation for the atlas, although this species certainly nests in many difficult to access blocks in the Coast Ranges (JG). https://ebird.org/atlascalifornia/checklist/S374470290

 
   Yolo County continues to grow its Atlas coverage thanks to the wonderful Yolo County birding community. All birders, naturalists, and keen observers of all skill levels are encouraged to join the project. Keep up the good work!
                       
Feel free to follow Yolo County Atlas statistics here: https://ebird.org/atlascalifornia/county/US-CA-113
 
For more information about the CBA: https://www.californiabirdatlas.org/

YouTube tutorial on how to join the project: https://www.youtube.com/shorts/8Z3kbqiO9rw
 
Thanks to the following for their reports:
Peyton Bounds, Laura Davis, Konshau Duman, Jonathan Eisen, Joshua Greenfield, Kelli O’Neill, Zane Pickus, Mark Sawyer, Kirk Swenson, Elliot Schoenig, Bart Wickel
 
Photos and Audio Recordings:
Blue-winged Warbler: https://ebird.org/checklist/S334287057
Scarlet Tanager: https://ebird.org/atlascalifornia/checklist/S353590466
Laughing Gull: https://ebird.org/checklist/S356353686
Black-throated Blue Warbler: https://ebird.org/atlascalifornia/checklist/S388462822
Northern Parula: https://ebird.org/checklist/S388429426
Indigo Bunting: https://ebird.org/checklist/S379339002
Hooded Warbler: https://ebird.org/atlascalifornia/checklist/S360339692
American Redstart: https://ebird.org/atlascalifornia/checklist/S336416658
Dusky Flycatcher: https://ebird.org/atlascalifornia/checklist/S334052272
Snowy Plovers: https://ebird.org/atlascalifornia/checklist/S375144549

–Zane Pickus