Date: 12/14/25 7:31 pm From: m_m_rogers via groups.io <m.m.rogers...> Subject: [southbaybirds] San Jose CBC - Alviso - Brewer's Sparrow, waterfowl, and others
All,
Steve Rottenborn and I birded Alviso ponds A9 through A15 today for the San Jose Christmas Bird Count. We started out from the EEC at 6:45am to search for Short-eared Owls along Pond A16 and Triangle Marsh north of Pond A15. We had no luck with any owls, but Steve picked out an AMERICAN BITTERN flying low over the marsh opposite southwest Pond A17 at 6:57am. We continued to work our way out to Pond A9, where we saw 7 BROWN PELICANS, 5 SNOW GEESE (2 adults and three juveniles, 7:30am to 7:52am), and later heard SHORT-BILLED DOWITCHERS - but all were outside the count circle. We did see an adult GREATER WHITE-FRONTED GOOSE (8:22am to 8:29am) on Pond A14 inside the count circle, though, along with an impressive tally of 10 male EURASIAN WIGEONS. A near-adult BALD EAGLE was later joined by an adult BALD EAGLE and seen on several occasions.
The most surprising bird of the day was a BREWER'S SPARROW that Steve picked out from the car at the northeast corner of Pond A15, not far south of the railroad track crossing. This is very late for a Brewer's Sparrow in the county (first December record, I believe) and is presumably a count first. It was a bit skulky and foraged around on the ground before flying up into a bush right in front of us, but too close to get the cameras to focus quickly. It then flew north along the road and landed in another bush (where Steve did get photos), before crossing the railroad tracks towards Pond A17. It was seen from 9:39am to 9:42am but could not be refound on a later visit to the same location just after 4pm.
Continuing between ponds A13 and A15, we added 10 SNOWY PLOVERS and a PEREGRINE FALCON on Pond A13. Searching thousands of scaup on ponds A10 and A11 failed to add any rarities other than an out-of-place male RING-NECKED DUCK. Also notable was a CLARK'S GREBE feeding a begging young bird (fully grown). The gull flock on Pond A12 was confined to the southern part of the pond and only numbered about 750 birds with no surprises. Gull numbers elsewhere were small, except for a couple thousand birds on Pond A17 after 4pm (not our area but nothing unusual among them either). Birding the Alviso Marina failed to turn up the Swamp Sparrow reported last week but did provide us nice photos of a cooperative WRENTIT. Two WHIMBREL were in the slough with curlews and godwits. We finally started seeing TREE SWALLOWS at 3:17pm and managed ten by 3:40pm. Driving back out to the Brewer's Sparrow spot we took advantage of the sun being behind us to scope Pond A16 (not our area). Steve estimated 500 REDHEADS and we digiscoped another EURASIAN WIGEON. We worked our way out towards Coyote Slough along Pond A17 to check for Short-eared Owls again and lucked into a vocal SWAMP SPARROW opposite southwest Pond A17 from 4:24pm to 4:28pm. Our owling effort again failed to locate a Short-eared Owl, but Steve found a GREAT HORNED OWL perched on a Drawbridge building across the slough (Alameda County) at 5:03pm (which followed seeing a MERLIN flying to Alameda County at 4:40pm).
Brewer's Sparrow location: 37.452406, -121.975501
Swamp Sparrow location: 37.454122, -121.974874 (the bittern landed near here too!)
Do not disclose information that identifies the location of nesting birds of any species, to minimize stress on the nesting birds and the risk of vandalism or abuse.
