Contra Costa County 1/21 (near-adult) Glaucous Gull, Pacific Loons, Continuing Eurasian Teal, etc

Logan Kahle

Hi All,

Yesterday (1/21) I spent a fun day bouncing around some of my favorite Contra Costa spots with C├ędric "Jugglerboy" Duhalde. We worked from Richmond east to East County, ending at Clifton Court. Waterbird action in Richmond has picked up significantly with thousands of cormorants along with loons, gulls etc foraging distantly in the Bay. It looks like there is some Herring Run action somewhere on the other side of the Bay.

Seeing a terrible (10+ minute?) wait to go the quarter mile west to the offramp of Point San Pablo, we decided started the morning at Miller/Knox instead. Our coverage was relatively quick and focused on waterbirds on the pond and bay. Highlights included:
'Aluetian' Cackling Goose-1 flew into pond
Eurasian Wigeon-3 but surprisingly no females
Lesser Scaup-1
Red-breasted Merganser-20 was a good count for the county
Black-bellied Plover-36 was a good count, presumably reflecting birds pushed up w the tide
Red-throated Loon-7
PACIFIC LOON-1 was the first in CoCo I've seen in almost two years, and traditionally quite rare overall
Golden-crowned Kinglet-1 up on the ridge
Brown Creeper-1

Full eBird checklist here:

Our next spot was Sandpiper Spit. We focused on looking at the jetty and offshore. Large numbers of birds were roosting on the jetty, presumably escaping the high tide. Highlights here were:
Black Turnstone-21 was a nice count for the jetty, counted in flight
Western Sandpipere-700 huge flock on jetty
Red-throated Loon-9
PACIFIC LOON-1 represents the only time I have seen two in the county on the same day
Double-crested Cormorant-1050

Full eBird checklist here:

We proceeded to Canal Boulevard for a better view of Brook's. The tide was higher than I have ever seen it at Brook's, with essentially zero (0) exposed shoreline. The slight drizzle predicted for the day was starting to pick up. We did not focus on jetty birds because we had a better view from Sandpiper Spit. Highlights here included:
Brant-37 was a good count for the county
BLACK SCOTER-1 may have represented one of the Richmond Marina birds, or possibly not
Red-throated Loon-4

Full eBird checklist here:

We continued onto Waterbird Regional Preserve, which held the most birds I have ever seen there by a good margin. Extensive mudflats and islands through the pond allowed for large numbers of Gulls to concentrate, something I have never seen previously at the preserve. Among the huge flocks of ducks and gulls were:
Mute Swan-6 (lowlight)
Blue-winged Teal-6 was my highest count for this location (and traditionally a challenging bird in the county)
Eurasian Wigeon-1 was a good bird here
'EURASIAN' GREEN-WINGED TEAL-1 continuing third county record found by Srikant Char earlier this winter. The horizontal stripe was hidden at times (making us briefly wonder if two birds were involved) so the bold white stripes on the face was perhaps easiest/most reliable way to pick the bird out from the American swarms
Hooded Merganser-13 was a good count for here
Lesser Yellowlegs-1
Thayer's Gull-2
Western Gull-2 were good birds here
'Olympic' (Western x Glaucous-winged) Gull-2
'Cook inlet' (Glaucous-winged x Herring) Gull-4
Forster's Tern-4

Full eBird checklist here:

From there we went to Bethel Island where we spent the next little while. We checked the fields in the central part of the island (including the north end opposite Piper Slough), all of which were dry, except the far northern fields. No good shorebird concentrations were present though there were good numbers of Blackbirds at certain spots. We then hit Piper Slough, Willowest Marina, Frank's Tract and finally the Golf Course. Passerine activity was low, and diversity of waterbirds at Franks and Piper was slightly lower than expected (at franks this was partially because the majority of the birds were really, really far away making ID impossible). Highlights here were:
Snow Goose-1300 which included a PURE WHITE individual with no black on the primaries! I have only ever seen one such individual before, and none in California
BARROW'S GOLDENEYE-1 adult male on Frank's Tract was only the second I have ever seen on the island
Common Gallinule-1
American Coot-12200, estimated, was about average. Likely double this number among the distant Franks Tract Swarms
'Thayer's' Gull-1
Sharp-shinned Hawk-1
Horned Lark-1
House Wren-1 was a low count
Orange-crowned Warbler-1 was a very low count
Yellow-rumped Warbler-5 was very low

Full eBird checklist here:

We took Dutch Slough rd over to Jersey Island hoping there might be some open water there. Not a whole lot on Dutch Slough spare a Cooper's Hawk and a Merlin (which seemed quite pale but I was unable to get a good view to determine subspecific identity).

Jersey was quite productive, though no exposed water was present. Likely due to the rain earlier in the day, large numbers of birds were using the fields to forage. A brief check of the island produced:
Ferruginous Hawk-1
American Pipit-280
White-crowned Sparrow-230
Yellow-rumped Warbler-100

Full eBird checklist here: <>

We next made a brief detour to Discovery Bay on our way south. We didn't have much time to bird but still managed to find a few interesting birds:
Hooded Merganser-2
Common Merganser-9
Glaucous-winged Gull-1
Red-breasted Sapsucker-1
Red-breasted Nuthatch-1

Full eBird checklist here:

From there we proceeded to our final real stop of Clifton Court Forebay. I had hoped to arrive at the Forebay no later than 4 but that did not turn out. This turned out to be not so great for us, as it was too dark to even partially sort thorugh the flock of 30-50000 gulls roosting in the middle of the reservoir. The only gulls we were really able to pick through were about 1000 birds roosting on the levee and allowing for great views. While driving through the swarm one Glaucous-winged Gull came towards the car, nearly entered through the open window but eventually veered off after slapping me in the face. Glad it didn't enter the car. It didnt appear to be harmed. Anyway, highlights of what we could make out on the forebay included:
Lesser Scaup-1000, most right in channel
Greater Scaup-3 was an interestingly low count
American Coot-6000 was a low estimate of the number present
GLAUCOUS GULL-1 third-cycle on levee was the oldest Glaucous Gull I have ever seen in California
GLAUCOUS x GLAUCOUS-WINGED GULL-1 first-cycle on levee was a nice study
Other gulls-30-50000 gulls were present on the reservoir, of which it seemed the vast majority were California and Glaucous-winged Gulls, which seemed roughly even in number (though big gulls outnumbered cal gulls by a decent margin). Other taxa present in lesser numbers included Herring Gull, 'Cook Inlet' (Herring x Glaucous-winged) Gull, and Thayer's Gull. It seems very likely that several Glaucous Gulls and one or more Lesser Black-backed and/or Slaty-backed Gull is currently present in the swarm if anyone wants to take on the challenge

Full eBird checklist here:

All in all was great to do my first all-day Contra Costa run since being back. Despite marginal weather we managed to find 133 species over the course of the day.

Good birding,
Logan Kahle
San Francisco