Tweeters,

The following trip report is late, but I only just received confirmation
scale insects were indeed the critters we observed.

WATERVILLE PLATEAU COUNTRY: OBSERVATIONS ON SNOW BUNTINGS and BOHEMIAN
WAXWINGS
22-23 FEBRUARY 2003

Ellen and I birded parts of north-central Washington this past weekend,
spending time on the Waterville Plateau, and about Bridgeport, including the
nearby Central Ferry Canyon Unit of the Wells Wildlife Area.

WATERVILLE PLATEAU (22 FEBRUARY). We began our visit on the Waterville
Plateau near Atkins Lake. Two weeks ago there was a complete snowpack
everywhere on the plateau, perhaps 10" deep. Today, the snow around Atkins
Lake and, indeed, the entire eastern, lower (2200-2400 feet) half of the
plateau
was essentially gone. The wheatfields were soggy and muddy. We saw no sign
of the huge numbers of Snow Buntings that swirled about this weedy (Russian
Thistle and Giant Mullein are conspicuous here) wheatfield two weeks ago;
instead, arctic Horned Larks and Lapland Longspurs were common.

At the Russian Olive grove on Heritage Road (one mile south of SR-174), we
spooked one lone Long-eared Owl, but missed the small flock of American Tree
Sparrows reported here, possibly because cold northerly winds which had been
increasing all morning, sent them into hiding.

>From there we did a broad-brush circuit of the higher elevation (2400-3100
feet)
western Waterville Plateau. West from Mansfield, the snowpack had only
partially melted. Indeed, the highest elevation part west of Lamoine and
south to Waterville still looked very wintry. In this large area, which lies
south of the Withrow Moraine, "clean cropped" wheatfields are the rule. We
saw few birds, save occasional paired Horned Larks (resident Merrills's
race) and a handful of Rough-legged Hawks, one Prairie Falcon, and the usual
number of Common Ravens.

Returning north towards Mansfield, and back into the stony, rough ground
north of the Withrow Moraine, on a lark, we stopped at Baseline NW and
picked out a modest number of Snow Buntings flying across a snowy field in
the distance. These birds settled down and disappeared. We trekked out into
the field where we found the exposed, snowfree south-facing aspects of the
swales attractive to both Horned Larks and Lapland Longspurs, while the
protected north-facing slopes, where snow still lay, held the Snow Buntings.
I estimated this one field held 300 birds, 100 each of Lapland Longspur,
Snow Bunting, and Horned Lark. I examined the plant cover of this wheatfield
in hopes of answering the question "what makes this particular field so
attractive to these birds in this sea of wheat?" I can say a weedy component
was noticeable. So, perhaps these visitors from the arctic search the
wheatfield country for fields with a high weed concentration, mostly
ignoring the clean-cropped fields. In other words, they are attracted to
fields where sloppy farming practices prevail.

LEAHY JUNCTION (23 FEBRUARY). We arrived before dawn at the vantage to the
Sage Grouse lek on 19 NE. It was cold! There was a stiff north wind and the
temperature was 20 F. We couldn't manage more than five minutes outside
searching the sagelands for grouse before retreating back into our vehicle.
On our first try, while it was still too dark to clearly see, I heard no
grouse above the wind, but did note a couple Gray Partridge giving their
scratchy calls. On the next try, after a few more minutes, I found the first
Sage Grouse atop a ravine edge several hundred yards to the north. Panning
our scopes, we found about six more grouse, all males. At one point, two
males engaged in a half-hearted duel, flapping their wings in an aggressive
posture then one backed off. We surmised them to be defending the edge of
their territory on the lek. A few minutes later, all the grouse disappeared
from view. Perhaps either the wind or a predator had frightened them off.
The only other birds we noted here were a few Horned Larks. Heading west
towards Mansfield, we enjoyed the stunning view west to the pink-hued Chelan
Mountains, bathing in early morning alpenglow.

BRIDGEPORT (23 FEBRUARY). A Blue Jay has been hanging out by a mobile home
ringed by nut trees (at least some are Hazelnuts), on the west side of the
main entrance to Marina Park in Bridgeport. The arctic wind was still
blowing at this exposed site, making lingering difficult. We did not see
this bird, evidently it wanders about town.

Birding the nearby A Bridgeport Bar Wildlife Area was a real pleasure.
Numerous rows of brush and trees, all introduced plantings, provided shelter
for lots of birds and us from the wind. We counted five Ruby-crowned
Kinglets, an unusual number for winter here, one Townsend's Solitaire, a few
Varied Thrushes, and lots of Song and White-crowned Sparrows. One singing
White-throated Sparrow spiced up our list. The nearby Columbia had lots of
waterfowl (Canada Goose, Mallard, Northern Pintail, Gadwall, American
Wigeon, Canvasback, Redhead, Ring-necked Duck, Greater Scaup, Common
Goldeneye, Bufflehead, Common Merganser, and Ruddy Duck), and American
Coots, as usual. Patrolling overhead were several immature Bald Eagles.

CENTRAL FERRY CANYON (23 FEBRUARY). We had a unique observation (in my
experience) of Bohemian Waxwings in Central Ferry Canyon. At the lower edge
of the Ponderosa Pines, at about 2300 feet, we stopped to see what was
about.
Immediately I heard the distinctive din (high-pitched notes, slightly
trilled) from a flock of Bohemian Waxwings. Initially, they were perched
high up in the pines. I thought this was a little unusual, but not totally
out of character. After a few minutes, the flock (~300), descended into a
thicket of Quaking Aspen. Now, this behavior seemed highly unusual. At first
I imagined them to be "budding," though on close inspection the buds still
appeared tight and in a dormant state. On closer viewing through our scopes,
it became clear the waxwings were gleaning from twigs and small branches at
all heights of the aspens and in shrubs below. We double-checked to make
sure these birds weren't finding berries and we were simply mistaken. We
both agreed the waxwings were honing in on naked portions of the twigs (not
at a bud cluster). I conclude these birds which are thought to be mainly
fruit-eaters from fall through spring, were gleaning from the twigs much as
a chickadee or kinglet might. Since aspens are prone to periodic insect
outbreaks, this seemed like a reasonable hypothesis and this large flock of
waxwings had discovered an unusual concentration of tiny insects. We then
inspected a twig and noticed numbers of scale-like insects (or pupae)
attached to the branchlet. These were barely visible to me without
magnification. Through reversed binoculars, we more clearly saw these were
distinctly bicolored, being ~ 2 mm long, cylindrical, mostly very dark
brown, but with a slate-blue mark forming a collar.

I took a branchlet from Central Ferry Canyon to Dr. Wee Yee, entomologist at
the USDA Agricultural Research in Parker Heights north of Wapato. With his
naked eye (I was impressed he could focus on these minute beings, I guess
proving my age), he instantly identified the critters as scale insects
(Homoptera), tentatively Diaspidadae, or Armored Scale insects. Under the
microscope (an astounding world!), he turned a female upside down (with
tweezers) to reveal it laden with eggs. He took one look at the density of
insect matter on this branchlet and commented the woods from which this came
had lots of protein for these birds, if this branchlet was typical. I will
mail the branchlet off to Dr. Richard Zack at WSU and ask him or his
associates for identification of these insects.

The only mention of waxwings eating scale insects in my references state
Cedar Waxwings are known to forage on these. I would assume Bohemians would
do this, also.

I asked Dennis Paulson to comment on our observation (prior to taking the
branchlet to Dr. Yee) and he replied:

"I looked in Bent's life histories, the only other place I know where one
can find such information [the Birds of North America account on Bohemian
Waxwing has not been published], and he says nothing about scale-insect
eating in this species. They eat plenty of flying insects, flycatching like
Cedar Waxwings do. He wrote that they eat tree sap
in spring, and I don't know if it's possible that there might have been sap
on the twigs or buds where you saw them, but you'd think there would be more
sap running from the trunk. I don't see any reason why they wouldn't eat the
scale insects, however, as I suspect they are opportunistic as so many birds
are, and it may be that fruit is getting fairly scarce by this time of year.
If the little critters looked like scale insects, I suppose they were, but I
know nothing about scale insects at the species level."

Dr. Yee mentioned to me some scale insects (aphids for example) exude a
sweet substance that should attract and be nutritious to birds, also.

Andy Stepniewski
Wapato WA
Steppie at nwinfo.net