Date: 5/9/26 8:50 pm From: Lance Benner via groups.io <lbenner...> Subject: [LACoBirds] California Bird Atlas Detailed Results for LA County
Hi Everyone,
Here's another update on progress with the California Bird Atlas in Los Angeles County.
These are results as of 2026 May 9.
Before launching into long lists of species and atlas blocks, let's discuss eBird hotspots near block boundaries, which is already a source of confusion in some areas.
The eBird hotspot at the Piute Ponds is perhaps the most pressing. The Piute Ponds area spans four atlas blocks so new eBird hotspots have been created for each one:
Piute Ponds CA Atlas Rosamond CE
Piute Ponds CA Atlas Rosamond SE
Piute Ponds CA Atlas Rosamond Lake CW
Piute Ponds CA Atlas Rosamond Lake SW
If you're contributing to the atlas at the Piute Ponds, PLEASE USE THESE HOTSPOTS! The older, general eBird hotspot for the Piute Ponds ("Piute Ponds (permit required)") is very close to a block boundary, was fine until January 1, but is too imprecise for the atlas. Using the new blocks is a pain but it's worth it because doing this will put your birds in the correct location and make your observations more valuable.
There are other eBird hotspots around the county that are close to block boundaries that we may discuss in in detail in future emails. For example, Huntington Gardens in San Marino spans two blocks: Most of the grounds are in Mount Wilson SW but thin section on the south edge is in El Monte NW. Bonelli Park in San Dimas is another location that spans four blocks.
Another easy way to deal with this situation is to set up your own personal spots and then use them every time you visit a particular area. A number of people are already doing this.
Back to our regular summary...
LA County eBird Atlasers: 648 (increase of 43 in the last two weeks)
eBird Checklists: 10,588
Atlas effort: 8402 hours
Atlas blocks with some data: 350 (81% of the total)
Atlas blocks with zero data: 84
Species with a breeding code: 245
Species with breeding confirmed: 134 (increase of 14 in the last two weeks)
54 species have been confirmed breeding in at least 10 blocks:
35 27 Canada Goose
11 10 Egyptian Goose
46 34 Mallard
12 10 Rock Pigeon
13 Eurasian Collared Dove
28 23 Mourning Dove
45 36 Anna's Hummingbird
49 47 Allen's Hummingbird
14 12 Killdeer
15 14 Great Blue Heron
18 15 Cooper's Hawk
18 15 Red-shouldered Hawk
47 45 Red-tailed Hawk
28 24 Great Horned Owl
13 Acorn Woodpecker
28 15 Nuttall's Woodpecker
64 51 Black Phoebe
17 11 Say's Phoebe
12 11 Vermilion Flycatcher
23 20 Cassin's Kingbird
12 Hutton's Vireo
30 25 California Scrub-Jay
50 47 American Crow
111 100 Common Raven
34 27 Oak Titmouse
13 11 Northern Rough-winged Swallow
14 Barn Swallow
29 22 Cliff Swallow
89 77 Bushtit
19 11 Wrentit
15 White-breasted Nuthatch
12 Blue-gray Gnatcatcher
42 21 Northern House Wren
38 30 Bewick's Wren
65 59 European Starling
39 30 Northern Mockingbird
43 26 Western Bluebird
13 10 American Robin
10 Phainopepla
17 16 Scaly-Breasted Munia
61 58 House Sparrow
104 84 House Finch
43 29 Lesser Goldfinch
10 Lawrence's Goldfinch
48 38 Dark-eyed Junco
53 42 Song Sparrow
69 47 California Towhee
22 10 Spotted Towhee
28 15 Hooded Oriole
13 10 Red-winged Blackbird
11 Brewer's Blackbird
10 Great-tailed Grackle
27 17 Orange-crowned Warbler
13 10 Common Yellowthroat
The number on the far left gives the number of blocks where breeding for each species has been confirmed. The number to the right of it, if present, indicates the number of blocks where breeding for this species was confirmed two weeks ago. If those columns are blank, then the number of blocks was less than 10.
Some species have seen significant increases: Northern House Wren (+21 blocks), Western Bluebird (+17), House Finch (+20), Lesser Goldfinch (+14), California Towhee (+18 blocks), Spotted Towhee (+12), and Hooded Oriole (+13).
Common Ravens, house finches, bushtits, European starlings, and house sparrows have been confirmed in the most blocks.
Los Angeles County blocks where breeding has been confirmed for at least 10 species:
14 11 Azusa SW
24 20 Baldwin Park NW
13 Beverly Hills CW
17 11 Beverly Hills NE
11 10 Bevery Hills NW
12 Burbank CE
34 25 Burbank SE
10 Burbank SW
10 Calabasas SW
12 Chilao Flat CE
10 10 El Monte CE
11 11 El Monte NE
16 10 El Monte NW
22 20 El Monte SE
23 18 Glendora SE
16 14 Hollywood CE
42 32 Hollywood NE
24 22 Hollywood SW
12 11 Inglewood CE
10 Inglewood SW
15 10 Juniper Hills NE
19 La Habra NW
12 Lancaster West NW
26 22 Long Beach CE
19 13 Long Beach CW
16 14 Long Beach NW
25 22 Long Beach SE
14 12 Long Beach SW
31 25 Los Alamitos CW
23 19 Los Alamitos NW
21 20 Los Angeles CW
11 11 Los Angeles NE
26 21 Los Angeles NW
16 15 Malibu Beach NW
12 Malibu Beach SE
14 Mint Canyon SW
14 11 Mount Wilson CE
11 Mount Wilson CW
31 30 Mount Wilson SE
30 27 Mount Wilson SW
28 22 Newhall CW
12 Oat Mountain CE
30 28 Ontario NW
41 37 Pasadena CE
31 27 Pasadena CW
10 10 Pasadena NE
29 25 Pasadena SE
10 10 Pasadena SW
10 Redondo Beach NE
11 Ritter Ridge NE
13 11 Rosamond CW
14 Rosamond Lake CW
14 Rosamond Lake SW
35 25 San Dimas CE
57 44 San Dimas NE
25 21 San Fernando SE
14 10 San Pedro NE
12 San Pedro NW
11 Torrance cW
23 12 Torrance SE
11 Torrance SW
20 17 Val Verde SE
15 Valyermo CW
21 16 Valyermo NW
33 30 Van Nuys CW
10 Van Nuys SE
31 29 Venice NE
13 13 Venice NW
11 11 Warm Springs Mountain CW
13 11 Whittier NE
17 12 Whittier NW
45 43 Whittier SE
Here the number on the left gives the number of species in that block that have been confirmed.
Two weeks ago there were 51 blocks on this list. Now there are 72!
Clearly we've been confirming breeding in a lot of blocks. One of the take away messages is that we're getting better at this and that the pace of confirming breeding is accelerating. It's also true that more species are in the process of carrying nesting material, carrying food, and feeding fledglings, so it's easier to see breeding evidence than it was a few weeks ago.
Note that 30+ species have been confirmed breeding in 13 blocks:
Burbank SE (34)
Hollywood NE (42)
Los Alamitos CW (31)
Mount Wilson SE (31)
Mount Wilson SW (30)
Ontario NW (30)
Pasadena CE (41)
Pasadena CW (31)
San Dimas CE (35)
San Dimas NE (57)
Van Nuys CW (33)
Venice NE (31)
Whittier SE (45)
San Dimas NE has the most with 57. This includes Bonelli Park where there is extensive diversity of habitat and frequent, thorough coverage.
Blocks with at least 50 species with breeding codes:
65 63 Baldwin Park NW
85 82 Burbank SE
51 Burbank SW
55 Chilao Flat CE
50 50 Chilao Flat SW
66 64 El Monte SE
59 57 Glendora SE
75 67 Hollywood NE
51 Hollywood SW
65 59 Lake Hughes CW
50 Long Beach CE
63 56 Long Beach CW
54 51 Long Beach NW
57 55 Los Alamitos CW
68 67 Los Angeles NW
66 65 Malibu Beach NW
72 64 Mount Wilson CE
61 61 Mount Wilson CW
52 Mount Wilson NE
56 54 Mount Wilson SE
67 67 Mount Wilson SW
52 Newhall CW
64 57 Ontario NW
83 76 Pasadena CE
62 61 Pasadena CW
54 53 Pasadena NE
73 68 Pasadena SE
52 51 San Dimas CE
96 82 San Dimas NE
89 82 San Fernando SE
55 Valyermo CW
68 65 Valyermo NW
75 68 Van Nuys CW
69 63 Venice NE
50 50 Whitaker Peak NE
66 65 Whittier SE
The number on the left gives the number of species with a breeding code. The number next to it, if present, gives the number of species documented two weeks ago. If blank, then there were < 50 species previously.
Here "coded" is the sum of possible + probable + confirmed breeding codes in the eBird portal for behavior such as singing, courtship displays, carrying nesting material, carrying food, feeding young, etc.
With the previous LA County Atlas in the 1990s, the organizers estimated a target number of species that should be present in each block, and of those, observers tried to find (i.e., assign a breeding code) at least 90%. Of the species coded, observers tried to confirm at least 50%.
During the previous atlas from 1995-1999, 50+ species were coded in 188 atlas blocks. So, after just over four months, we've already coded 50+ species in 36 blocks, which is 19% of the total from the 1990s. Thus, we are ahead of the pace during the previous atlas.
Brief Recap of Important Things from Previous Emails
Atlas Effort:
To see how much effort has been contributed, such as number of hours, number of species coded, confirmed, complete checklists, etc. go to:
Then enter "Los Angeles" into the "Explore Atlas Regions" field. This shows the broad summary I provided above plus detailed results for each species and each atlas block.
Joining the Atlas:
If you haven't contributed to the bird atlas yet, joining is easy. On a computer, go to https://ebird.org/atlascalifornia/home, scroll down a bit, and look for the green button marked "Join Project" on the left. Click on it and then you can contribute!
On a phone, start the eBird app, go to the settings, select the "Portal," and then select the California Bird Atlas.
If you haven't contributed to the California Bird Atlas, please join us! We'd love to have your help!
