[EBB Sightings] RW Blackbirds Lake Temescal

During an after-dinner walk at Lake Temescal, a group of at least 200 RW Blackbirds was making a ruckus in the cattails and trees on the north side.  A neighbor who walks his dog nightly said that they have been there for at least 2 weeks.  I usually walk the lake in the morning, and  there are 10-20 around then.  I've not observed such numbers earlier in the day.  Are these migrants?

Other birds noted:


Green Heron
BC Night Heron
Mallard
Amer Coot
Ring-bill Gull
Black Phoebe
Western Scrub Jay
Stellar's Jay
CB Chickadee
Bushtit
Brown Creeper
First year female Yellow Warbler
Song Sparrow

Pat Bacchetti
Oakland