Where have all the chickadees gone?
Tue, 27
Apr 2004 14:45:59 PDT
From: Bill Gilbert
E. B. birders,
I just completed a seven-day survey of areas of the Tilden Nature Area (Berkeley Hills) to tabulate numbers of permanent-resident arboreal species. As soon as I state the numbers in my survey someone likely will respond that they just saw a dozen Hutton's Vireos during a 15-minute walk through their neighborhood. But here goes anyway.
The genesis of my impromptu survey was that I had noticed relatively few individuals of permanent-resident arboreal species in the TNA this spring. Specifically, I had noticed few Chestnut-backed Chickadees, Bushtits, Hutton's Vireos, or Brown Creepers. Steller's Jays, arboreal permanent residents but with different feeding habits than the four species just mentioned, have been present in their normal obnoxious numbers. Also present in seemingly normal numbers are permanent-resident understory species (Wrentit, towhees, junco, Song Sparrow, etc.) and migrant arboreal species (Black-headed Grosbeak, Warbling Vireo, Pacific-slope Flycatcher, Orange-crowned Warbler, etc.). Orange-crowned Warblers, in fact, have bounced back well from several low-number years to abundance in the TNA this spring. My survey of number of permanent-resident arboreal individuals seen or heard is as follows. The respective numbers after each species are the number of individuals recorded in riparian habitat (10 total observation hours), oak woodland habitat (8 total observation hours), and in the two habitats combined (18 total observation hours):
This limited survey does not suggest that the last three species mentioned are gone, and sightings by myself and others have recorded a few individuals of the three species recently at other local sites and/or earlier this year in the TNA. In fact, Larry Tunstall and Terry Robertson both reported seeing Bushtits on Tuesday morning in areas to the north and east of my survey area (possibly better Bushtit habitat). They reported no Hutton's Vireos nor (I believe) Brown Creepers, however. Even though some individuals of all these permanent-resident arboreal species no doubt are present, my survey does suggest that their numbers may be significantly reduced this year. Put another way, when one encounters about the same number of Winter Wrens as chickadees in the TNA riparian areas, something seems odd.
If my observation is valid (it is a limited survey in a small area, and I have no count data from past years to compare with), then interesting questions are "How widespread?" and "Why?" I cannot guess how widespread, but can advance some preliminary speculation on why. I observed a paucity of late summer migrant and permanent-resident arboreals in the TNA last year, and even chickadees (usually the most common arboreal species) seemed relatively scarce. I saw no mixed-species flocks, and chickadees normally are the core species for such flocks in the TNA. If low late-summer food supply (in the canopy of oaks, willows, etc.) caused these low numbers, then this might not have affected the subsequent survival of fall migrant arboreal species very much. Those species perhaps could have found better feeding grounds once migration started, or may have spent little time in the TNA if just passing through from other breeding grounds. Permanent resident arboreals may not have had the option of finding "greener pastures," however They may have been dependent on local food supplies through the fall and the winter as well. If their fall and overwinter food supplies were down, some may not have survived.
This is speculation, and may not be correct. Feedback on numbers of permanent-resident arboreal species being seen other places would be interesting, however, as well as feedback on their numbers in the Christmas bird counts.
By the way, I have yet to see any "through" migrant species (e.g., tanagers, Dendroica warblers) in the TNA this spring, but have no idea why.
Bill Gilbert
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What season is this, anyway?
Tue, 27 Apr 2004
16:14:44 PDT
From: Sylvia Sykora
On Sunday in my garden in Oakland near Skyline/Castle Drive I had Golden-crowned Sparrows feeding on the thistle seed that fell as the American Goldfinches fed; begging juvenile Dark-eyed Juncos following a harried parent; ditto four or five Chestnut-backed Chickadees; the first seasonal calls from the Olive-sided Flycatcher at the top of the deodar; nesting Purple Finches in the climbing hydrangea; two Violet-green Swallows above the lawn; and a flock of 10 Cedar Waxwings calling and landing in another deodar. The young juncos and chickadees are about two weeks earlier than usual; the flycatcher's right on time; the sparrows may have to stick around for another two weeks.
Re: What season is this, anyway?
Tue, 27 Apr
2004 18:21:16 -0700
From: Ore Carmi
Sylvia Sykora wrote:
The young juncos and chickadees are about two weeks earlier than usual....
So are Bushtits. In the past approximately 3 years, I've generally noticed Bushtit fledglings around May 1. However, this year, I've been seeing fledged Bushtit young on the University of California Berkeley campus and in my West Berkeley neighborhood for already more than a week,
ore carmi
Berkeley, CA
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Tilden Nature Area, Berkeley Hills
Tue, 27
Apr 2004 20:18:51 -0700
From: Larry Tunstall
Alan Kaplan's East Bay Regional Park District birdwalk at Tilden Nature Area (Berkeley Hills) on Tuesday morning wandered up the hill behind the Little Farm to Loop Road, which we followed to Jewel Lake. Highlights included many Wilson's Warblers, Orange-crowned Warblers, and Pacific-slope Flycatchers singing, American Robins carrying nesting material, Chestnut-backed Chickadees busily coming and going from a nest cavity, and Dark-eyed Juncos feeding youngsters. We did see or hear at least half a dozen Brown Creepers, including a group right at the intersection of Loop Road with the main fire road from Jewel Lake to the Visitors Center. Highlight of the morning was a Yellow Warbler singing from the top of eucalyptus at the intersection of Loop Road with Laurel Canyon Road. We thought we heard another singing near Jewel Lake.
One song most of us thought was a Bewick's Wren, but when we found the bird visually, it was a Song Sparrow. A minute or so later, it switched to a standard Song Sparrow song and repeated that as long as we were there.
Here's what I caught of the group's collective list:
By the way, the small flock of White-crowned Sparrows that winter in my yard in El Cerrito departed right on the usual schedule last week.
Good birding, Larry
Larry Tunstall
El Cerrito CA
Mines Road, southeast of Livermore
Tue, 27
Apr 2004 20:26:54 -0700
From: Russ Wilson
Hi All -
On Saturday April 24th the Golden Gate Audubon Society's annual field trip on Mines Road (out of Livermore) produced most of the hoped for target birds. After scouting out the territory, veteran leader George Bing knew where to find the following:
Of course there were many more of the backyard variety - but those were some of the the highlights.
Russ Wilson
El Cerrito
Re: Blue Grosbeak on Patterson Pass Road
Tue,
27 Apr 2004 20:37:30 -0700
From: Debbie Viess
I am heading off to Patterson Pass Road tomorrow morning for (I hope) a sighting of the Blue Grosbeak. Haven't been out that way for years ... what exit do I take off of Hwy 580, to get to mile marker 6.21? I have a detailed map of the area...
Thanks for any timely help that you can provide,
Debbie Viess
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Re: Where have all the chickadees gone?
Tue,
27 Apr 2004 21:30:36 -0700
From: Lee Ellis
Both Chestnut-backed Chickadees and Bushtits are still present in my small Fremont yard in their usual numbers. Cork oaks are the predominant trees here. Yesterday I saw chickadees gleaning insects from my roses.
Maybe you didn't see as many, because, as others have observed, they are nesting and raising young.
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Re: Where have all the chickadees gone?
Tue,
27 Apr 2004 21:35:48 -0700 (GMT-07:00)
From: Diane Perry
Here in Walnut Creek (near Northgate High School) our standard back-yard Chestnut-backed Chickadee pair are as evident as ever. Very busy at the feeders. Also, suddenly the Oak Titmice have come back after an absence of some months, and are enjoying the safflower seed I've put out for them very much (while the rest of the birds go "eh" at it). We seem to have had the same chickadee pair living in our backyard for years now, but it must be several generations of the same family. They are quite tame: we can get 2 or 3 feet from them before they fly away.
Diane Perry
Walnut Creek
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Bald Eagle near Orinda
Tue, 27 Apr 2004 21:42:02
-0700
From: Kitty O'Neil
I saw a (the?) Bald Eagle flying over Briones Dam this afternoon. (Off Bear Creek Rd just east of San Pablo Dam Rd in Orinda, East Bay Municipal Utility District Trail Permit required unless you are just driving by and happen to see it, but don't crash your car!)
Good Birding, Kitty
Kitty O'Neil
Orinda, CA
Re: Where have all the chickadees gone?
Tue,
27 Apr 2004 21:49:32 -0700
From: Lisa Owens-Viani
Lee Ellis wrote:
Both Chestnut-backed Chickadees and Bushtits are still present in my small Fremont yard in their usual numbers.
Lots of both in my small Berkeley yard too.
Lisa
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Re: Blue Grosbeak on Patterson Pass Road
Tue,
27 Apr 2004 21:54:53 -0700
From: Arlyn Christopherson
Debbie Viess wrote:
what exit do I take off of Hwy 580, to get to mile marker 6.21?
Debbie,
Coming from Oakland, I took the Vasco Road South exit off Hwy 580 (at the far end of the Livermore valley). Several miles down Vasco, turn left on Patterson Pass Rd (it has a left turn lane) and just kept following it. It gets smaller and smaller and finally gives up even having a yellow line down the middle. Watch out for crazy commuters who are not used to seeing oncoming traffic and just whiz down the middle of the road. You will actually be descending on the other side of the hills when you come to the marker. There is a little place to park just past the marker. Good luck.
Arlyn
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Re: Blue Grosbeak on Patterson Pass Road
Tue,
27 Apr 2004 23:23:04 -0700
From: Rich Cimino
Hi Debbie
Take Hwy 580 - the last exit in Livermore is Greenville - follow this south for 1.5 miles. Patterson Pass Rd turn is just before the Livermore Labs; it will be a left hand turn. Enjoy and be careful of the traffic.
Rich Cimino
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