Date: 4/29/25 2:33 pm From: David Assmann via groups.io <david_assmann...> Subject: [SFBirds] Migrants and breeding birds at Fort Mason
Over the last two days there has been a slight increase in migrants moving through Fort Mason. Yesterday, there were two BULLOCK'S ORIOLE (one a brilliant male in full alternate), two WESTERN KINGBIRDS and an OLIVE-SIDED FLYCATCHER. Today, I observed 1 WESTERN KINGBIRD, 1 BLUE-GRAY GNATCATCHER, 1 SAVANNAH SPARROW, 1 WILSON'S WARBLER (this species doesn't nest at Fort Mason, as far as I've observed), 1 BLACK-HEADED GROSBEAK and 1 LAZULI BUNTING. The wintering birds have pretty much cleared out, with 1 remaining GOLDEN-CROWNED SPARROW, 1 HERMIT THRUSH, 1 FOX SPARROW and 13 YELLOW-RUMPED WARBLERS - down from 49 on April 18th). The resident GREAT HORNED OWL was being mobbed in flight by 14 AMERICAN CROWS. Lots of breeding activity and newly fledged birds. There were/are two active NORTHERN MOCKINGBIRD nests in the garden. Early yesterday morning two chicks were being fed in one of the nests, with one still in the nest and the other near the top of the shrub above the nest. Later in the morning, the more active chick was walking through the garden. It would take a few steps, then raise its wings as if it were about to try to fly, and then resume walking (it did this multiple times). The adult MOCKINGBIRDS were constantly driving away AMERICAN CROWS. See attached photos.
