Hi tweets

Relatively large (+30-50) flocks of southbound Northern Flickers are fairly
regular on the lawns of Jericho Park on Vancouver BC's West side. Usually
they arrive a bit later in the fall-;weeks 1 and early week 2 Sep seems a
titch early. While the vast majority are Red-shafted, it's always worth
thrashing the flock(s) to shake out any Yellow-shafted and hybrids from the
contact zones.

What might be worth looking into is what exact environmental factor
triggers the southbound movement of northern and interior NOFL populations
and whether they selectively migrate to and along the western Pacific coast.

best wishes, m