Numbers in the high hundreds and perhaps low thousands are regular for short
periods in late September and early October in coastal Lane County dune
thickets. At that time of year hybrids are hard to tell. I am rarely in that
habitat in late April and early May so I don't know what the flow is like or
what the percentages are. Myrtles come through the Eugene area in small
numbers in spring, sometimes in small single-species flocks. I recall seeing a
flock of seven or eight Myrtles at Delta Ponds two years ago.
I might see one obvious hybrid per spring, but my spring birding is limited; I
am more of a fall birder.
.
.
Alan Contreras
acontrer56@xxxxxxxxx
Eugene, Oregon
On Apr 17, 2015, at 4:46 PM, Craig Tumer wrote:
On the few forays I've made into the field this week (all in the northern
Willamette Valley), I, like seemingly everyone else in western Oregon, have
seen large numbers of migrant YELLOW-RUMPED WARBLERS. The vast majority of
those I've seen well have been Audubon's Warblers, and the majority of those
identified by call note have been Audubon's, as well. I've also seen small
numbers of Myrtle Warblers and three obvious Myrtle x Audubon's intergrades.
Two of the three intergrades were in one flock that also contained at least a
dozen Audubon's and two Myrtles. All of the intergrades were adult males with
throat patches with shapes typical for Myrtle Warbler, but with bright yellow
centers and clear, white borders.
On the East Coast, it's not uncommon to see hundreds or even thousands of
Yellow-rumped Warblers in a day in coastal waxmyrtle thickets, and while
living there, I got into the habit of looking and listening for different
behaviors and call notes among the huge numbers of "butter-butts" rather than
trying to look at each individual bird in an attempt to find something
different among the masses. The numbers of yellow-rumps I've encountered in
Oregon have not been so overwhelming, and there's often a mix of Myrtles and
Audubon's. So, recently, I've started looking at the Yellow-rumps more
carefully and not taking them for granted. Within the past five days, I've
seen fifty Yellow-rumps very well, and three of those have been obvious
intergrades. That seems like a pretty high proportion. Is that typical, or
have I just been lucky? Just how prevalent are Myrtle x Audubon's
intergrades here?
Craig Tumer
SW Portland
OBOL archives: www.freelists.org/archive/obol Manage your account or
unsubscribe: //www.freelists.org/list/obol Contact moderators:
obol-moderators@xxxxxxxxxxxxx
