Today, 3/24/21, I walked a CCW route on the Alviso Slough Trail. Walking on the east side, I heard calling by a Caspian Tern in flight over Pond A16. I don't know when they install the tern recordings or whether they do that anymore. Lots of ducks on Pond A14, including two male EURASIAN WIGEON. I returned by Pond A12 and saw a 1st-cycle GLAUCOUS GULL at the far edge of the gull flock in late afternoon.