Date: 6/12/26 1:16 pm From: Van Pierszalowski via groups.io <van...> Subject: [CALBIRDS] California Bird Atlas Big Weekend 2026 Results
Hi birders,
I’m happy to report that the inaugural California Bird Atlas Big Weekend (June 4-7, 2026) was a tremendous success! Thank you so much to our partners for organizing 54 (!) field trips and events throughout the state in a single weekend. Special thanks as well to our incredible Regional Coordinators ( https://ebird.org/atlascalifornia/about/regional-coordinators ) and the broader atlasing community.
Amazingly, 47% of the confirmed breeding codes recorded during Big Weekend represented new confirmations (species breeding in atlas blocks where they hadn't yet been confirmed). This highlights the strategic approach atlasers took throughout the weekend, focusing their efforts on expanding coverage and documenting breeding evidence where it mattered most. Many atlasers reported using Blockboard ( https://cba-blockboard.share.connect.posit.cloud/ ) to help identify these opportunities.
See a recap of Big Weekend statistics below. For a deeper dive (plus some of our favorite photos from the weekend), check out the News post ( https://ebird.org/atlascalifornia/news/big-weekend-review ) on the CBA eBird platform.
BIG WEEKEND BY THE NUMBERS
* *4,180* Atlas checklists were submitted
* *1,211* atlasers submitted checklists, including *181* first-time atlasers
* *1,575* blocks received data, including *194* blocks that had not previously received Atlas coverage (see the News post ( https://ebird.org/atlascalifornia/news/big-weekend-review ) for a map)
* *26,809* breeding codes were submitted, including *6,121* confirmed-level codes
* *308* species received breeding codes, including *226* species with Confirmed-level breeding codes
* *4,865* confirmed breeding "block ticks" (each species in each block = one block tick), including 2,287 new confirmed block ticks
DISCOVERIES
* What appears to be the first confirmed breeding record of *Canyon Wren* in Solano County was reported ( https://ebird.org/atlascalifornia/checklist/S354320273 ) by Eric Pilotte at Stebbins Cold Canyon Reserve on June 7.
* Atlasers added two new species to the Atlas’s list of confirmed breeders: *Bufflehead* ( reported ( https://ebird.org/atlascalifornia/checklist/S352892908 ) by Sam Eberhard in Lassen County) and *Green-winged Teal* (reported in three different blocks — two in Plumas County, one in El Dorado County).
We will be organizing CBA Big Weekends every year throughout the Atlas period (2026-2030), and it will be exciting to see how the results evolve from year to year. Thank you again to the incredible birding community, and here's to another great atlasing weekend starting now.
