Hi Tweets,

The last couple of Lost Lagoon counts I did turned up one and two hybrid
Yellow-rumped Warbler (YRWA) males out of total YRWA counts of 13 and 10
birds, respectively.

At a survey location (Donna Creek) about 250 km N of Prince George BC and
about 50 km W of the Rocky Mountain Trench in north-central BC, out of the
total YRWA local breeding population, we had several breeding pairs (about
5% of total breeding pairs) of YRWA in which the males were Audubon X
Myrtle hybrids, others in which the pair was male Audubon X female Myrtle.
Not one pair included a male Myrtle. Never saw male Myrtles in the area
except during a heavy migrant wave of Auds and Myrts at the beginning of
the survey in mid-May. I think they breed considerably further north.

Frequency of obvious hybrids in the general Cascadian migrant population?
Probably not that rare: there seems to be a pretty good-sized hybrid zone
in central and northern BC. When you see hoofprints in the sand, think
horses, not zebras ;-)


Michael Price The only alien planet is Earth.
Vancouver BC Canada
mprice at mindlink.net - J. G. Ballard