Piper Slough
Tue, 1 Sep 1998 12:24:25 PDT
From: Steve Glover
Birders,
This morning I got out to Piper Slough before it really started to get hot
and had a pretty good morning. The highlights were 2 Bank Swallows amongst
at least 110 Tree Swallows, 2 Cattle Egrets flying north, and at least 9
Willow FLycatchers. There were also fair numbers of western migrants including
Orange-crowned, Wilson's, and Yellow Warblers, 1 Western Tanager, 1 Black-headed
Grosbeak, 1 celasphorus hummingbird. A few birds that may be lingering breeders
or migrants were also present including a male Yellow-breasted Chat, 2 Western
Kingbirds, and a female Blue Grosbeak feeding a full grown fledgling.
Good luck,
Steve Glover
Jewel Lake
Thu, 3 Sep 1998 21:06:31 PDT
From: Steve Glover
East Bay Birders,
This morning I spent about an hour birding at Jewel Lake in Tilden Regional Park. It was not quite as birdy as it was last Friday when I was there but there were a few different birds. This morning there were 3 Winter Wrens (one last friday), 3 Townsend's Warblers (five last friday), 1 Black-throated Gray Warbler (3 last Friday), 3 Warbling Vireos (0 last Friday), and 6 Wilson's Warblers (23 last friday, nearly all males). Last Friday there was also one Western Tanager and one Yellow Warbler. I encourage anyone with the time to check this area as much as possible as there have been more records of vagrant passerines from here than everywhere else in the county put together. While you are at it this park is full of potentially good spots that could be successfully mined for goodies.
Good luck,
Steve Glover
Richmond area
Sat, 5 Sep 1998 12:52:50 PDT
From: Steve Glover
East Bay Birders,
This morning we headed out to Richmond. There was no wind and the bay was exceptionally placid. From Pt. Isabel we saw a Common Murre swimming towards [Alameda County]. A Brandt's Cormorant also flew by. Brandt's probably occurs with some frequency but it hard to detect for an interesting reason. Because of the angles of the shore and the bay around Pt. Isabel and Brooks Is[land] very few of the birds fly by straight from the perspective of a land-based birder. This can make it very tough to see if the cormorant has a straight neck and short tail. We then scoped from the end of Marina Bay Parkway. The male Harlequin Duck was in front of the island with about 125 Surf and at least 2 White-winged Scoters. I saw what I also felt was the female Harlequin Duck. The weeds and willows across the street from Miller/Knox Regional Shoreline at Pt. Richmond had 1 Pac[ific]-slope, 2 Willow Flycatchers, 1 Swainson's Thrush, 5+ Orange-crowned Warblers, 2 Wilson's Flycatchers, 2 Common Yellowthroats (migrants here), and 2+ Western Tanagers. It wouldn't surprise me if there were interesting birds all over the bay area with the high clouds and calm winds.
Good Luck,
Steve Glover
Chestnut-sided Warbler, possible Least
Flycatcher
Tue, 8 Sep 1998 16:11:44 PDT
From: Steve Glover
East Bay Birders,
This morning I went out to Jewel Lake hoping that the weather change had dropped in some migrants. Actually it dropped in very few. I had 3 Orange-crowned Warblers, 5 to 6 Wilson's Warblers, 3 Black-throated Grays, and 6 Townsends. There were no Warbling Vireos. On the way out I stopped to check a small flock of chickadees and creepers. While looking at a Townsend's Warbler I spotted the top of the head of another bird. The top of the head was lime green! I watched the Chestnut-sided Warbler for about 10 minutes. This was a county bird for me, bringing me to 299. The warbler was at the start of the packrat trail at the end of the parking lot. I got the best views by walking up the "stairs" (railroad ties) and looking down. At the base of the trail I also had an empidonax flycatcher that I am unsure what to do with. This empid was quite dull underneath, duller than any Western I can remember seeing. Disturbing to me was what I perceived as a very slight yellowish tinge to the throat. In fact it was so faint that I was never sure if there actually was any yellow. It would seem like any true yellow would rule out Least. The back was also quite dull, leaning toward what I would call olive-brown. The head was well rounded (not peaked). The bill appeared completely orange-yellow underneath but may have had a hint of duskiness at the tip.
I had trouble nailing down the exact shape of the bill but it was too wide to be a Dusky or Gray. The eyering widened behind the eye and although the shape was not well defined it was not teardrop-shaped. The wings had two prominent bars that were brownish. The primary extension was pretty short (much shorter than Hammond's, probably not quite as short as Dusky/Gray. In summary, I have ruled out Hammond's based on bill shape/ color and primary extension, Dusky and Gray based on bill shape and color, primary extension and overall color, and Willow based on eyering and bill size and shape. This leaves "western" and Least, two species that I don't think should be that hard to tell apart. The primary extension is very similar on the two species, as are the bills. I guess what is giving me the most trouble is the yellow that I may or may not have detected in the throat. Apparently "Western" can be worn to the point of having very little or possibly even no yellow below. I think that most of the features I noted fit Least quite well. Needless to say, the bird never called or I wouldn't have this problem. If you go look beware that there was at least one [Pacific-slope Flycatcher] there.
Good Luck,
Steve Glover
RE: Chestnut-sided Warbler, possible Least
Flycatcher
08 Sep 98 17:14:02 -0700
From: Les Chibana
Steve,
Regarding the empid you described:
I banded or measured 5 Western (WEFL) and 2 Willow Flycatchers (WIFL) this past Saturday at Coyote Creek Riparian Station. The WIFLs were fairly standard, but the WEFLs presented some challenge. All were hatch-year birds (incomplete skull development) with buffy wingbars. Most of their throats were only faintly yellow. The bill measurements were well within the WEFL range. However, one had a dusky distal 1/4 of the underbill, and, in this respect, was not all that different from the WIFLs with about 1/3 distal underbill duskiness. The wing measurements of the WEFLs were quite varied and some were visibly different than the others. But all were within the range of measure for WEFL in the new Pyle's Guide. The WEFL with the dusky underbill tip was also the individual with the smallest wing measurements. Its eyering appeared to not be so pointed at its widest measure to the rear of the eye. But that was when I was hoping that it would turn out to be something else. Considering the appearance of some of the individuals that I was able to measure, my feeling is that the bird you described could have easily been a Western Flycatcher.
Les Chibana
Palo Alto