September 1998 Field Journal 9.4 [SFBirds] No Blackpoll Warbler at East Wash
Visibility was pretty good, but birding only so-so at the East Wash. Best
birds were a female-plumaged MACGILLIVRAY'S WARBLER and a couple of SWAINSON'S
THRUSHES giving a call which might be described as "oink" (e.g. not the
typical "whit" call).Middle Lake was teeming with birds high in the canopy above the lake, many
of which were not readily identifiable in the early morning fog, though there
were a couple of WARBLING VIREOS I managed to find.9.5 [SFBirds] American Redstart at Fort Miley Trees
Brian Fitch called this in this afternoon. Alan and I checked this area
"thoroughly" this morning but did not see it. To get to this area, find the
bathrooms at the rear of the Legion of Honor. From the bathrooms, walk more
or less west towards the VA until you find some trees near some picnic benches.
I believe the bird was in the cypresses where there is a large flock of
migrants and PYGMY NUTHATCHES.9.5 [SFBirds]
Nothing great, but RED-BREASTED NUTHATCH was easy to find in the East Wash.
Strawberry Hill had a pair of BLACK-THROATED GRAY WARBLERS, but there was no
trace of the WESTERN KINGBIRD at Stowe Lake. Other than a cloud of SOOTY
SHEARWATERS at the south end of the Great Highway, only another BTYW at
Sunset Circle about 1/2 way down towards the fishing beach was notable.9.6 [SFBirds]
I managed to find a/refind the NORTHERN WATERTHRUSH at Middle Lake this
morning. It teetering in some willows about eye level just northeast of the
junction of the trail which runs along the southern edge of the lake and the
trail which leads into the glade. If this is the same bird as the found by
Kevin M., it might be thinking about wintering as it's been here since 8.25.Middle Lake
Northern Waterthrush
Swainson's Thrush
Black-throated Gray Warbler
Western Tanager
Pacific-slope Flycatcher
Hermit WarblerTrees along El Camino Del Mar
Hutton's Vireo
Red-breasted Nuthatch
Wilson's Warbler
Black-headed Grosbeak
East Wash
Western Tanager
Warbling Vireo
Bullock's Oriole
Pine Siskin9.8 [SFBirds] Blackpoll Warbler at Bercut
This morning, the M.Ob. refound the Blackpoll Warbler at Bercut. Light was quite poor
and the bird was foraging near the top of the some tall pine trees just behind
the magic eucalyptus tree. I thought I had refound the PRAIRIE WARBLER, but
fortunately the M.Ob. showed up and discovered a misidentified TOWNSEND'S
WARBLER. So much for birding with a cold... :-|9.8 [SFBirds] Re: Blackpoll,Acorn, Shearwaters
The bird was observed by several people for an extended period in atrocious light at the top of mature pine trees. Subtlies in coloration certainly were not possible. Given these caveats, I will nonetheless plunge headlong into this abyss...The bird didn't appear to have a strongly contrasting cap, though I never got a good look at the top of the bird. Indistinct eye ring which was slightly paler than the rest of the face. Eyering broken fore and aft by a dark eyeline. Auricular and other facial regions were indistinctly darker than the coloration on the upper breast.
Coloration on the breast ended somewhere about midbreast, but I don't seem to remember exactly where. Upper breast indistinctly streaked darker along the sides, much as the auricular region contrasted with other facial regions. Belly and undertail coverts were white. Wings had two strong wingbars which seemed to be uniform across the entire folded wing.
Now, we come to something that bothered me. My impression was that the tail was relatively long, though I can't be sure I wasn't looking at the undertail coverts instead of the tail proper. Also, I did not notice much (any?) dark at the out tips of the rectrices nor any contrast between the end of the undertail coverts and the rectrices. However, I also seem to remember a somewhat notched appearance in the tail, though this impression is fleeting at best.
Referring to D&G, perhaps the photographs are the most useful. The bird on page 391 bears a striking resemblance to my mental picture on GGP bird, complete with broken eye ring, indistinct dark regions on the face and a cap which doesn't strongly contrast with the rest of the face, though this bird does not have any streaking on the sides of the upper breast like the GGP bird does. Also not the photograph on page 390 indicating how pale these birds can get, and also that the tail can give a somewhat notched appearance.
In the plates, the bird strongly resembles (a) of the first fall Blackpoll Warblers. Bay-breasted Warbler appears to be ruled out by the distinctly white undertail coverts. Eliminating Pine Warbler is slightly more difficult, particularly since tail extension might be a better fit. Also, note the following comment in D&G:
"Pines show considerably more white in the tail, with the white areas on the outer two rectrices about twice as long as those of Blackpoll and Bay-breasted."
Face pattern doesn't appear to match Pine Warbler, though the separation between cheeks and throat appears indistinct in the first fall female bird in Plate
19 of D&G.Pine Warbler is a CBRC species. Most CA records of Pine Warbler come from mostly mid-October and November. The only two records from September are a record from 9.21.73 from SE Farallon Island and another record from 9.25.85 from Briceland in Humboldt county.
I'd love to read other writeups of the bird from this morning.
9.9 [SFBirds] 9.9.98 Lake Merced
The willows north of the concrete bridge were fairly quiet this morning. In
particular, we didn't manage to find the flock of bushtits.Across the road, there were some migrants high in the pines of the Olympic
Club, but only a HERMIT WARBLER was notable.9.12 [SFBirds] 9.12.98 SF Birds
Dan's covered many of the highlights, but here's a few additional tidbits. The MAGNOLIA WARBLER was still in its usual place in the Community Garden behind 1308 Kobbe Stree in the Presidio. I arrived right at 7:00 and there was nothing at all moving. Then I hear a soft 'tsup' or 'tslep' and tried to imitate. The warbler immediately flew from its roost in the tree just above the pumpkin scarecrow at the edge of the garden. David and Joost showed up right around the time that the bird disappeared, but it was refound it later just uphill from the garden where the brambles start.>From there, we caravaned to Lobos Creek and walked in. No WESTERN KINGBIRD, but we did find the LARK SPARROW in the middle of the path shortly after departing from the boardwalk. Continuing along the dirt path along the creek and into the willows, we found a bird that we eventually identified as a BLACKPOLL WARBLER. There was also at least one LINCOLN'S SPARROW there and we had a flock of CEDAR WAXWINGS in the cypresses near the parking lot at the hospital.
On the return to the cars, I called Luke and he mentioned that Alan had found the GREEN-TAILED TOWHEE, so we decided to head over. We arrived and the towhee wasn't currently being seen, but Hugh had an interesting empidonax flycatcher which he was chasing in the brambles and fennel below the plateau. Calvin, Hugh and I spent some time down there but the bird escaped firm identification. At this point, Alan refound the Green-tailed Towhee and we attempted to run up the trail to the plateau, with success inversely proportional to our waistlines. :-)
Everyone managed to get on the bird for good looks other than me and I was still breathing hard and getting more than a tad frustrated. Finally, I scrambled up the hill to a vantage point above the brush pile (Which brush pile? _That_ brush pile? This one? No, the other one.) Anyway, I waited impatiently for a couple of minutes and the Green-tailed Towhee popped out for a great look. At this point, another sparrow popped up (in yet another brush pile) which looked to me like a CLAY-COLORED SPARROW.
The bird was a spizella with a prominent, unmarked gray nape. The auricular region was rich buff, outlined in darker buff top, rear and bottom. Eye line did not continue in front of the eye, giving the impression of pale lors. Supercilium appeared (very) pale buff in certain light, with significant contrast between the auricular region, outline and crown. Distinct dark submoustachial line and distinct pale (buff?) eye ring. Crown was brown streaked with black and split with a pale median stripe. Breast was clear, and I do not seem to recall any contrast between the breast and the throat. Back and rump were brownish, with no contrast between the rump and the back. Notched tail. The bird was photographed by both ASH and MWE.
Other birds of note were perhaps 3 or 4 VAUX'S SWIFTS in a mixed swift/swallow flyover flock, a cooperative BLUE-GRAY GNATCATCHER and another LINCOLN'S SPARROW. Though I did not see them, CHIPPING SPARROWS were also reported in the wash. At this point, Dan's group showed up and mentioned the birds he had found at Middle Lake. Most of us left for Middle Lake at this point, but did not find any vagrants once we arrived.
9.13 [SFBirds] Worm-eating Warbler coming to a feeder in SF (???)
There's a report on the Birdbox of a WORM-EATING WARBLER that's been coming
"regularly" to a feeder at 29th and Lake in the mornings and evenings and
"scaring off the HOUSE FINCHES". Immature/female BLACK-HEADED GROSBEAK9.14 [SFBirds] Brewer's Sparrow still behind Bercut
Kevin McKerrigan refound the BRSP behind Bercut this morning, of course
after I had left for work.9.15 [SFBirds] Palm Warbler in East Wash
Josiah and Steve Davies had a PALM WARBLER in the East Wash this morning.
Further details on the location may be found on the Birdbox.9.15 [SFBirds] Brewer's Sparrow still behind Bercut
This morning, Hugh refound the BREWER'S SPARROW in the maintenance yard behing Bercut Equitation Field. The bird was foraging with a flock of juncoes in and around the gardener's debris box.Notes from memory:
A spizella with a long notched tail. Crown streaked brown, continuing through the nape, brighter in coloration than back coloration. No median crown stripe. Bill short and pale in coloration. Pale gray coloration on the face. Brown eye line which continued around most of the auricular patch. No significant contracst between auricular patch and rest of the face. Extremely faint submoustachial line. Back pale gray, heavily streaked with brown and black. Outer tertial edges buff. Wing coverts tipped in white, giving the impression of two thin, white wing bars. Upper breast pale gray with very faint darker gray streaks along the outer breast.This is probably a hatch year bird.
At Middle Lake, activity was high and diverity low. We had a selasphorous hummingbird which we identified as a RUFOUS HUMMINGBIRD as it's back was solid rufous for the lower 2/3 of the back.
Bercut
Brewer's Sparrow
Hairy WoodpeckerMiddle Lake
Swainson's Thrush
Rufous Hummingbird
Yellow Warbler9.15 [SFBirds] Just when you thought it was quieting down...
Josiah found (get this) a NORTHERN PARULA, a CHESTNUT-SIDED WARBLER and a
PROTHONOTARY WARBLER on the west side of North Lake "above the footpath".
It's not clear where along the footpath the birds were, though I'd guess once you
find the flock, you'll find the birds.9.16 [SFBirds] Chestnut-sided Warbler still at North Lake
No sign of the Prothonotary Warbler or the Northern Parula, though...North Lake
Chestnut-sided Warbler
2 Lazuli Bunting
2 Wood Duck
Warbling Vireo
Yellow Warbler
Fox Sparrow
Red-tailed Hawk
Orange-crowned Warbler9.16 [SFBirds] Buntings at North Lake
BTW, the subject of the buntings at North Lake came up tonight in Joe's
class. Did anyone get a real good look at these birds (I saw two this morning)?
Are we sure that they were LAZBs instead of INBUs? Identification of fall buntings
can be very tricky.9.18 [SF Birds]
The PROTHONOTARY and CHESTNUT-SIDED WARBLERS were still on the west side of North Lake this morning. They were ranging well up and down the west side, so you might need to walk a bit to find them.I also refound both buntings this morning, feeding on the bare area/path which separates the two lobes of the lake. One of the buntings is showing small amounts of lazuli coloration on the head and the rump and hints of cinnamon on the breast which seem to indicate hatch year male LAZULI BUNTING.
The other bunting is more problematic. It has noticeable streaking on the breast and sides of the flanks, quite unlike the extremely faint vestigial streaking on the Lazuli Bunting. While I won't attempt to summarize the vaguaries of separating Lazuli Bunting from Indigo Bunting in this plumage (see http://fog.ccsf.cc.ca.us/~jmorlan/march.htm for a discussion by the heavies on this matter), the following comment from Joe seems to summarize my difficulties:
"The vast majority of Indigo Buntings show clear unambiguous blurry streaks across the breast."
I did not attempt to analyze in detail the wingbars, but immatures from both species can show wingbars. Apart from probability and guilt-by-association, I'd be interested in an analysis based on field marks which indicates that both buntings are LAZBs, rather than a Lazuli Bunting and an Indigo Bunting which is what I wrote this morning. (N.B. I already have Indigo Bunting on my year list :-)
Calvin and I birded the Arboretum and found nothing in the California section.
We then went to the Horseshoe Pits. This area is north east of the Conservatory, more or less directly across from the hospital. South and above the pits, we found a pair of BLACK-THROATED GRAY WARBLERS and an ACORN WOODPECER was easy to see in the scrub oaks. We also managed to refind David's bird.
The bad news is that it's not a BLACKBURNIAN WARBLER, but the good news is that it's interesting. In good light at eye level, it looks just like a TOWNSEND'S WARBLER with a pale throat. In fact, I seem to recall that the yellow on the face may not have gone all the way to the collar on the warbler. After rereading D&G, I believe that this is a hybrid TOWNSEND'S x HERMIT WARBLER, as there is a plumage of Townsend's Warbler X Hermit Warbler which resembles a pure Townsend's Warbler with a pale throat.
North Lake
Prothonotary Warbler
Chestnut-sided Warbler
Lazuli Bunting
Indigo BuntingAbove Horseshoe Pits
2 Black-throated Gray Warbler
Acorn Woodpecker
Townsend's Warbler X Hermit Warbler9.22 [SFBirds] Cape May Warbler still at Middle Lake
This morning, the M.Ob. descended on Middle Lake and managed to refind the bird. The bird was spending most of its time hopping around a prominent cluster of dead eucalyptus leaves about 2/3 of the way up the large, prominent eucalyptus at the southeastern edge of the glade at Middle Lake. The best viewing is from the northeastern edge of the glade, which allows a convenient elevation but distant looks even with 10x nocs. Some of us managed to get brief scope looks. A technique which appeared to work well was to focus the scope at the top center of the dead cluster of leaves and wait for the bird to return to the cluster.Despite all of the observers and scopes, I have to say my sightings were brief and incomplete. Noc views were just identifiable and I had the bird in the scope for at most 2-3 seconds. Sky was high overcast, making precise determination of colors difficult. Nonetheless, here are my notes. Like Hugh, I must comment on how much I must have missed.
A wood warbler with prominent black streaking along the entire breast and well down the flanks. Throat and breast were yellow, turning to white at mid-belly. Undertail coverts and much of under rectrices white. Head yellow with contrasting olive crown and back. Dark eye line above top of cheek patch which contrasted with the yellow face. Cheek patch a pale olive smudge, perhaps with the slightest bit of warm brown mixed in. Dark wings, wingbars not well observed (no excuses here...) Bill not well observed. Rump not observed.
Maybe I'll try again tomorrow and bring my scope with me. Has anyone managed to photograph the bird?
9.22 [SFBirds] COTE at Crissy Field
Lisa Hug report COMMON TERNS at the Coast Guard Pier at Crissy Field this
afternoon.9.23 [SFBirds] Add another to the SF breeding list for this year
I just remembered; Calvin and I had 5 CALIFORNIA QUAIL, including a
juvenile/immature in the California section of the Arboretum.9.24 [SFBirds] No Pectoral Sandpiper, yes Long-billed Dowitcher
The PECTORAL SANDPIPER was not present at the little beach this morning nor near the concrete bridge. However, there was a LONG-BILLED DOWITCHER, presumably the same bird that Hugh found, south of the west end of the concrete bridge. I managed to get close enough to fill almost my entire field of view with the bird without flushing it, and it gave a single, sharp "kek" note at my point of closest approach.With such a good view, I was curious whether or not the bird could be identified on field marks alone. The bird appeared to be in juvenile plumage. The scapulars had dark centers, edged with reddish-brown. The edges of the scapulars had dark barring, while the tertials had dark centers, edged pale with no detail to the center of the tertials. The breast had little streaking on it and there was little rust on the underparts. There was little barring on the flanks, some of which was indistinct. Kaufmann tends to suggest that this does indeed suggest Long-billed Dowitcher, as the scapulars and, in particular, the tertials of Short-billed Dowitcher are far more detailed in this plumage.
9.26 [SFBirds]
Here's my recount of the rather remarkable day we had today. Cast of
characters was myself, Dan M., Hugh C. for all but Fort Funston, Ken
Goss was with us through the Crissy Field portion, and Harry was with
us earlier. Day appears in chronological order.Middle Lake:
Without looking particularly hard, Dan M. managed to refind the CAPE
MAY WARBLER. It was in the usual location, though might not be there
as frequently as it was before. It hung around long enough for the
sun to come out and for me to get four (distant) shots of the bird
with my camera. At the north end of the glade was also a NASHVILLE
WARBLER that Harry found.Bercut:
Zippo.North Lake:
The PROTHONOTARY WARBLER was easily relocated very near the water in
the berry brambles on the isthmus between the two halves of the lake.Cliff House:
Shortly after arriving there, Dan picked up on an unusual bird
floating past the Cliff House. I managed to pick up on it shortly
thereafter and identified it as an adult SABINE'S GULL. ELEGANT TERNS
were everywhere and there were at least two PARASITIC JAEGERS chasing
the terns.East/West Wash
Nada.Coast Guard Pier at Crissy Field:
Terns were everywhere down there, including at least 28 COMMON TERNS.Battery East/West
Hugh suggested that we head up to Battery East for "ten minutes". We
dragged our scopes up to the observation platform and started looking.
Then, all hell broke loose. I found a bird directly overhead which I
dismissed as "gull". Fortunately, Hugh took a slightly longer look
and immediately recognized it as a BOOBY sp. Details of this
observation and a subsequent analysis will be under a separate cover.As well, we had three relatively small buteos with fat wings.
Eventually, we noticed the dark tips and trailing edges of at least
one of the birds and realized we had three BROAD-WINGED HAWKS.
Another bird in this remarkable stretch was a large falcon. The lack
of any overt facial markings and dark axillaries and inner wing
linings identify this as a PRAIRIE FALCON. There was also a flock of
VAUX'S SWIFTS going overhead.At this point, we were seeing quite a few raptors but were hampered by
contrasty lighting for many of the observations. At this point, we
moved over to Battery West for vastly improved lighting and came up
with the raptor counts listed below, including a flock of 15 NORTHERN
PINTAILS flying by, a flock of 40 or so BAND-TAILED PIGEONS, more
VAUX'S SWIFTS and a nice adult PARASITIC JAEGER.Fort Funston Skyline Grove:
After I left Hugh and Dan M., I went to the Skyline Grove at Fort
Funston. There was a small warbler flock in the cypresses shortly
after you enter the grove. While I was looking for a PALM WARBLER,
about the third bird I found was a nice fall adult female MAGNOLIA
WARBLER. After looking at quite a few YELLOW WARBLERS, I finally
refound Calvin's Palm Warbler in the same flock. There was also a
BLACK-THROATED GRAY WARBLER in the same flock and even more VAUX'S
SWIFTS were flying overhead.Middle Lake
Cape May Warbler
Nashville Warbler
Orange-crowned Warbler
Yellow Warbler
Townsend's Warbler
Yellow-rumped Warbler
Warbling Vireo
Pacific-slope Flycatcher
Olive-sided Flycatcher
Willow Flycatcher
Swainson's Thrush
Hutton's Vireo
Cedar Waxwing
Western TanagerNorth Lake
Prothonotary Warbler
Ruby-crowned Kinglet
Fox Sparrow
Hairy Woodpecker
Wilson's Warbler
Warbling VireoCliff House
2 Parasitic Jaeger
Elegant Tern
Sabine's GullEast Wash
Western Wood-PeweeCoast Guard Pier
28 Common TernBattery East/West
Brown Booby
1 Prairie Falcon
36 Sharp-shinned Hawk
22 Cooper's Hawk
14 Red-tailed Hawk
3 Broad-winged Hawk
12 Turkey Vulture
35 Vaux's Swift
15 Northern Pintail
7 Accipter sp.
2 American Kestrel
60 Band-tailed Pigeon
2 Osprey
40 Band-tailed Pigeon
Parasitic Jaeger
Spotted TowheeFort Funston
Magnolia Warbler
Palm Warbler
Black-throated Gray Warbler
12 Vaux's Swift9.26 Blue-footed Booby
Technical Details:
Species: Blue-footed Booby Sula nebuouxii
Date Observed: 9.26.98
Observer: Mark Eaton
Other observers: Hugh Cotter, Dan Murphy
Location: Battery East, just south east of the Toll Plaza at the Golden Gate Bridge, San Francisco
Time Observed: About 12:15 PM
Lighting: Bright sunlight and no clouds. Sun bird angle was only about 30 degrees, leading to very dark shadows
Weather: Strong north or northwest wind
Optics Primarily Swarovski 10x42SLC binoculars, with views through a Swarovski AT80HD scope only as the bird was far distant
Distance: The bird flew directly overhead and was probably 150' to 200' above us initially and flew west southwest from there until the bird disappeared over a ridge.Below is a writeup from memory:
A large seabird with a large, heavy bill and a long, wedge-shaped
tail. The bill was both long and massive, becoming much more so at
the basal end. The bill shape smoothly transitioned into the head of
the bird in flight. The underparts of the tail were entirely dark
brown. The wings were very long, relatively narrow and were strongly
crooked at the wrist. The underparts of the wings also appeared
entirely dark brown. Breast and belly were bright, unmarked white.
The head appeared off-white, due either to smudging or streaking in
the head area. The smudging transitioned cleanly to the white breast
with no clear demarcation between the head and breast areas.
Upperparts of the bird not observed. Vocalization not heard.Booby identification can be quite problematic, particularly for
immature boobies, particularly since the standard NA Field Guides such
as NGS do such a poor job on sulids. Fortunately, this bird appears
to be an adult bird due to the crispness of its plumage. NORTHERN
GANNET adult has black-tipped wings, pointed white tail. NOGA
juvenile has a dark head, mostly dark wing linings and a grayish
belly. BROWN BOOBY has clear demarcation between breast and neck in
all plumages. Adult RED-FOOTED BOOBY light morph has almost all white
wing linings, pure white head. RFBO brown morph is wholly grayish
brown. RFBO, white-tailed morphs have tail white or yellowish white.
RFBO juvenile wholly brown or blackish-gray. RFBO intermediate has
patchy underwing, lacks streaking on head. Adult MASKED BOOBY has all
white head, extensive white on wing linings. Juvenile and immature
MABO have dark heads.BLUE-FOOTED BOOBY juvenile has dark head and is easily confused with
with BRBO. Adult BLUE-FOOTED BOOBY has streaked head, pure white
underparts, wing linings which are largely dark other than rectangular
patches on axillaries, white central tail feathers. However, plate
306 of an adult BFBO in "Seabirds of the World" by Peter Harrison,
taken in what appears to be similar ligthing conditions as on the day
of the observation, shows very little white on wing linings,
particularly on lower wing on the bird. As well, the white central
tail feathers do not show up well on in the bright contrasty light.While the observation was performed in less than ideal conditions, I
do feel that the observation was sufficient to identify the bird as an
adult BLUE-FOOTED BOOBY, even though I have no previous field
experience with this species.9.28 [SFBirds] Re: more on Sunday birds
Murphy Family wrote:
>
> That restoration area at Lobos Creek is getting pretty good. In
> addition to the stuff mentioned in other e-mails add a Savannah Sparrow
> spotted by David or Joost and missed by me. I think Joost suggest we
> should keep track of what's seen here to use as evidence for the
> positive impacts of such restoration projects. It's a really good
> idea. So far swallows, flycatchers and warblers seem to have used the
> area to one degree or another. Among the seed eaters, the sparrows are
> appearing too. Perhaps from now on folks who are interested could post
> species lists for the restroation area. I keep a file for the
> conservation committee.
>Nice idea. BTW, Hugh and I had at least 3 SAVS, all sitting in the same
bush, in the middle of the restoration area. Would have made a nice picture in
better light.9.28 [SFBirds] Black-throated Blue Warbler still present at Skyline Grove
This morning I refound the male BLACK-THROATED BLUE WARBLER at Skyline
Grove. It was feeding in large bush with thin, shiny oval leaves with pointed tips,
reddish-purple berries and small white flowers (pittisporum?) just north and
east of the last cypress on the eastern side of the trail. I had
spectacular looks in great light for close to a minute before it flew down and toward
me, but I could not relocate it after that. There was also a BLACKPOLL WARBLER
about 1/3 of the way from the south end of the grove on the west side of the
trail and a HERMIT WARBLER at the south end of the grove. I'm still not
sure I found everything in there this morning.If birding in the city isn't interesting enough for you, Rich found a YELLOW-GREEN VIREO in the lighthouse trees at Point Reyes this morning.
9.29 [SFBirds] Least Flycatcher at Fort Funston
After birding with David Nelson and Mark Stephanson this morning and not refinding the BLACKBURNIAN WARBLER, I finally refound it just after Mark left (fittingly enough). Other birds seen were the BLACK-THROATED BLUE WARBLER reported by David and a couple of HERMIT WARBLERS.I was on my way out when I ran into Luke and gave him a few tips on the birds. As I left the grove, I happened to notice that the large grove of cypresses along the paved trail (above and slightly south of the southern Skyline Grove) seemed very birdy as well. On a whim, I headed up for a quick look.
I almost immediately found an empidonax flycatcher. The eye ring was well-defined and circular, though not broad, broken at the top front of the eye. The forehead was very steep at the base of the bill, giving the bird's head a very rounded look. The bill was short and triangular, with the lower mandible almost entirely pale. The wings had very short primary projection. The tail appeared long, but it was hard to tell given how short the primary projection was. The yellowish wash on the belly extended all the way down onto the undertail coverts. The bird had an odd, nervous twitch of its wings each time it flicked its tail. The bird did not vocalize. After I lost sight of the bird, a WESTERN FLYCATCHER came into view, and the differences were immediately obvious. I went to find Luke and left him searching for the bird as I needed to head to work.
Possible vagrant empidonax flycatchers in fall need to be well-scrutinized. The short primary projection alone rules out most other common western flycatchers including Willow, Western, Dusky and Gray. Hammond's has a short triangular bill, but only rarely shows pale on the lower mandible, and then only on the basal half of the lower mandible. Also, Hammond's have long primary projection. I seem to recall the throat being white and the eye ring being white, which would tend to rule out Yellow-bellied, which is even less likely in CA than LEAST FLYCATCHER. Buff-breasted is easily ruled out on coloration alone.
It must be pointed out that I have no previous field experience with this species.
9.29 [SFBirds] Re: Fw: Least Flycatcher at Fort Funston
gerald wrote:
>
> Mark, Hugh said he had a Least in that grove last night, David NelsonI didn't know that Hugh found the LEFL last night, but I was aware that
Steve Glover had reported one. Anyway, it's still there.9.30 [SFBirds] Yellow-green Vireo, Black-throated Blue Warbler, Blackburnian Warbler and much more...
Perhaps we should rename the Skyline Grove as the "Lighthouse Trees".I received Brian Fitch's report shortly aft4er noon and decided more or less immediately to head out. I arrive some time around 1:00 and started looking . Lohn Luther was there and Mark Stephanson from Tucson joined us shortly thereafter. Pretty quickly, we managed to find a CLAY-COLORED SPARROW and a WHITE-THROATED SPARROW. Mark pointed out an unusual looking bird at the edge of the norther Skyline Grove and we watched it as flew to the northern edge of the southern Skyline Gove It looked good for Yellow-green Vireo and an d we followed it into a small scrubby cypress. I managed to get a slightly longer look thatn Mark did and was 90% convincced before it flew away. Little did I know it would take three hours to refind.
We then star4ed working our way through the grove and finally found an interesting flock of warblers. The flock contained a pair of BLCK-THROATED GRAY WARBLERS, a BLACKPOLL WARBER and John found the BLACKBURNIAN WARBLER. At this point, Joe showed up followed shortly thereafter by Josiah. All of us started workgin the grove adn shortly thereafter, most of the birds decided to abandon the grove, perhpas to head to the Y grove. Things got pretty slow for quite awhile and we ranged far and wide. Joe managed to refind the BLACK-THROATED BLUE WARBLER at the extreme northern end of the North Skyline Grove, but stil no vireo.
At this point, it wa about 4:30 and the light was already starting to fade slightly. Josiah and John were actually leaving the grove when Josiah refound the YELLOW-GREEN VIREO, on the west side of the trail just north of hte bunker. Not five minutes later, Calvin and David showed up (timing is everything!). A search ensued and teh vireo provded elusive again, but we noticed that warbler activity was picking up again at the south edn of the South Skyline Grove. We worked our way south again and David found the YELLOW-GREEN VIREO sitting in plain virfew on one of the cypresses at the south end of the grove. It took awhile, beut we managed to get everyone on the bird for good looks.
Technical Details:
Species: Yellow-green Vireo, Vireo flavoviridis
Date Observed: 9.30.98
Observer: Mark Eaton
Other observers Joe Morlan, Josiah Clark, John Luther, David Nelson, Calvin Lou
Location: Skyline Grove, Fort Funston, San Francisco
Time Observed: On and off from 4:30 until about 5:15
Lighting: Dull overcast, though lighting was ample for birds not in dense shade.
Weather: Heavy overcast and slight mist
Optics: Swarovski 10x42SLC binoculars
Distance: Initially, about 50 feet, but prolonged observation from 30 feet or less.Below is a writeup performed from memory the evening of 9.30.98
Description: A warbler-sized songbird with a relatively long, stout
bill. Bill coloration was mostly pale, with highlights appearing bone
colored. Crown was gray in color, demarcated from the white
supercilium with a relatively indistinct darker gray line.
Supercilium demarcated from the rest of the face by a similarly
colored, equally distinct eye line fore and aft of the eye. Eye
appeared dark. Cheek and throat white, smoothly transitioning to the
greenish yellow on the upper breast and flanks.Belly whitish, with no sharp transition between flank coloration and
belly. Undertail coverts strongly colored yellow with just a small
amount of green in it. Back and nape yellowish green, uniformly
colored all the way to the auricular region. Wings similarly colored
to back; no contrast all between wings and back, giving the bird a
very uniform and almost dull appearance despite the brightness of its
plumage. Tail relatively short and square; no contrast between upper
tail and back.Posture was quite unusual. The bird spend most of its time with it's
tail cocked up at an angle of about 45 degrees relative to its back,
giving the impression of a wren. As well, its wings appeared to be
slightly drooped, reminiscent of the posture of the DUSKY WARBLER last
fall in Santa Cruz. At one point, the bird nervously moved its head
from side to side while maintaining its tailed cocked. The bird spent
most of its time between ground level and roughly fifteen feet off the
ground, often feeding in mixed flocks including other warblers and
bushtits. The bird was not heard vocalizing.Discussion: The stout bill eliminates all wood warblers with the
exception of chats. YELLOW-BREASTED CHAT can be eliminated by lack of
spectacles, yellow undertail coverts and other facial markings. Chats
from the genus _granatellus_ can be eliminated by plumage,
particularly on the rectrices in the case of females. Within the
genus _vireo_, most species can be eliminated due to the combination
of a lack of wingbars and lack of spectacles. RED-EYED VIREO can be
eliminated by the brightness of plumage and the amount of yellow on
the upper parts. BLACK-WHISKERED VIREO can be eliminated by the
absence of a black whisker. WARBLING VIREO can be eliminated by the
lines above and below the supercilium and pronounced yellow-green
upper parts. PHILADELPHIA VIREO has a dark eye line, yellow throat in
fall, no line separating the supercilium from the crown and lacks
strong yellow-green upper parts. BROWN-CAPPED VIREO _V. leucophrys
amauranotus_ has a brown crown. YUCATAN VIREO _V. m. magister_ has a
broad whitish supercilium and bold dark eyestripe.The observer wishes to thank all of the other observers for their
efforts in locating and tracking this elusive bird. This was truly a
joint effort in locating the bird. Special thanks must go to Josiah
Clark for refinding the bird, David Nelson for his additional
correspondence on this subject and Joe Morlan for his helpful field
comments, particularly on aspects of the birds behavior.Earlier in the day, I birded Middle Lake and Sutro Heights along with Kevin McKereghan. There wasn't much of interest other than Kevin finidng a PROTHONOTARY WARBLER at Middle Lake and having the bird fly off to the south. Other birds which are potentially of interest to Big Year participants:
Middle Lake
Varied ThrushSutro Heights
Golden-crowned KingletMerrie Way
Golden-crowned Kinglet
House WrenWhat's next?
9.30 [SFBirds] More on Least Flycatcher Identification
This comes directly from Kaufmann's Advanced Birding (emphasis his):"Preliminary Points III: What _Not_ to Look for on an Empidonax"
...
_Yellow belly_: All Empids have yellow bellies, especially when they are in
fresh plumage. The brightness of the yellow varies more with age and season
that it does according to species. The brightness of this yellow may
provide a clue as to the freshness of the plumage, but only in this very indirect way
does it have a bearing on the specific identification.9.30 Booby sp.
I described the Booby to Joe tonight and he said (slightly paraphrased):"With that description, I'd tick off BLUE-FOOTED BOOBY and not think twice
about it". He was totally unconcerned about the lack of underwing detail in the
observation.Home
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