Date: 6/5/26 7:47 pm From: Michael Mammoser via groups.io <mmammoser...> Subject: [southbaybirds] Purple Martins at Calero
I stopped by Calero Reservoir this evening, 5 Jun 2026. Between 6:00 pm and 6:45 pm I had at least 10 PURPLE MARTINS cavorting over the peninsula just on the west side of the boat launch. As in recent years, females were landing, picking up small bits of shell, and swallowing them. I saw this same behavior a few days ago by a female LESSER GOLDFINCH. Also, CLIFF and TREE SWALLOWS were landing and picking at the ground, but I couldn't tell if they were obtaining shell or not.
Michael Mammoser
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.
