Green morph Pine Siskin in Concord, CoCo. County
On January 3rd, 2021 in Concord, Contra Costa County, I found a rare "green morph" Pine Siskin. Only two other records for California were known to this date, however, interestingly another "green morph", Pine Siskin, was also found on the very same day in Placer County.
I found this bird among at least 120 regular Pine Siskin, this "morph" resembles to some extent, well known to me from Europe, the Eurasian Siskin (Spinus Spinus), however there are some features that distinguish the two.
For the last few days I have tried to re-find this bird but with no success, although many Siskins are still foraged in this part of town these days.
Although the "green morph" Pine Siskin is considered very rare (about 1% of the US population), in this 2020/2021 season, however, the chance of finding it has increased (Pine Siskin eruption). Based on the eBird map of the current "green morph" distribution of Pine Siskin, you can already see clusters of records from the Northwest, Washington state / British Columbia, and also from the Northeast United States.
There is a good chance that this year will bring more records from the Bay Area, so next time you will see a flock of Pine Siskins, watch carefully for "green morph"
Albert W. Linkowski