Tuesday, September 19, 2017

Just How Common Is A Black-throated Gray Warbler . . .?

. . in the Bay Area?

. . . at this time of season?

I put the question to the EBB_Sightings Yahoo Group: "I was fortunate to see a Black-throated Gray Warbler at Mortar Rock Park in Berkeley the other day. Audubon page says the bird is widespread and common. I've only seen this bird one other time, at Sibley Volcanic Regional Preserve a couple of years ago. Does anyone see a Black-throated Gray Warbler commonly?"
I fielded three responses:

Judi S. said, "I think they are more often seen around here during fall and spring migration. I saw 2 together in Wildcat about 10 days ago."

Makes total sense. I wonder if those two are her only sightings? The adult female I saw was accompanied by a male consort, who largely stayed hidden, barely affording a flitting glance. But it ups my total to three, actually!

j ellis reported seeing the birds "only occasionally during migration. SF Botanical Gardens, Coyote Hills RP and Ardenwood Farms RP in Union City is where I see them this time of year."

So j seems to spot them fairly frequently, depending on migration patterns, and specific locations in the Bay Area.
Kay L., always knowledgeable, wrote that "Black-throated Grays may be common and widespread somewhere; but certainly not in the Berkeley area. Don't know which Audubon page you're referring to; but I'd tend to distrust the distribution comments for any species unless the site is specific to a fairly narrow area. (For example, if the site were focused on birds of the East Bay, and had comments on frequency or distribution, I'd be inclined to trust it more than a similar site that talked about all of California, or the whole United States.) FYI, neither the Alameda or Contra Costa County Breeding Bird Atlas show any indication of 'widespread' or 'common'. Like you, and me, I think most Bay Area birders consider it a treat to see one of these birds."

So, based on my small sample size, the jury is out: Black-throated Gray Warblers tend to show up semi-(ir)regularly in the Bay Area, but rarely in Berkeley. If lucky and diligent, and of course with specific timing, the birds might be seen a handful of times during the spring and fall migration periods.
My tally over the years = a grand total of two sightings, three birds. So, which is greater? The odds of me being in the right place at the right time, on two occasions? Or, the odds of me either being or not being in the right place to not spot them? The latter, for most certainly, I've been in many places at the right time, but, possessed of poor timing, I simply have not spotted more of the B-t Grays, or any number of other so-called rare birds passing through the Berkeley area during spring or fall migration - such as the Northern Waterthrush or Western Kingbird.
eBird's Occurrence Map for Black-throated Gray Warblers is an animated gif map that distributes their presence in accordance to preferred breeding locales, like a kaleidoscope of movement over time, through the seasons during different times of the year when they move to and fro to take up residence in Douglas Fir, Juniper and Pinon Pine in the desert Southwest, as well as the Sierra Nevada and the Pacific Northwest.

Evidently, they're common avidenizens of North America, but to see them in the Bay Area, and especially in Berkeley, I have to side with Kay L., for birder enthusiasts, it is special to spot one of pretty, fairly rare birds.

Sunday, July 9, 2017

Of Black-headed Grosbeaks, Warbling Vireos, Great Blue Herons, and Swainson's Thrushes

All season long, I've been enchanted by the "drunken Robin" arias of our old pal, the Black-headed Grosbeaks, whose vocal emanations euphoniously fill the sweet air with high-pitched whistles and squeaky chips. Roosting and feeding high up in hidden tree tops, whistling away while they work and play, these big-billed birds go after insects, seeds, berries, whatever they can get their beaks on, whenever and wherever the pickings are ripe. Currently, they seem to be feasting in the rich sylvan and riparian environs of  the Tilden Nature Area, a gem of the East Bay Regional Park District system of urban/wild parklands.

I tend to associate sightings of these birds with Springtime, not the middle of summer. (Not that I even see them all that often.) Well, birds are known to come and go at their whim, depending on so many factors, influenced by so many variables - it must make their tiny heads spin. Luckily, their bird brains have devised very successful survival strategies spanning unfathomable millions of years, going back to the dinosaurs, who, actually, did not die out as commonly presumed, but evolved into - you guessed it: BIRDS!

Well, as luck and timing, and circumstance and forbearance, would have it, the black-headed birds have eluded me this season . . . until just the other day.

Moments before, I had honed in on my first Warbling Vireo in two years, obsessed with a playful pair darting in and out of a clump of fragrant bushes springing up on a tiny islet created by Jewel Lake's diminished mid-summer water. Hanging on precarious stems, the handsome birds were in seed heaven sampling the bounty at hand - competing with a bold trio of Lesser Goldfinches and a whirling dervish of an adept insect-snatching Black Phoebe. With the characteristic white stripe above the eye, and a distinctive song and call set, the Vireos are otherwise drab in appearance, but I get excited every time I see one, because (in my estimation) the birds are noteworthy for their occult and furtive ways. Except, of course, when they're not shy to show themselves. But even then, I'd be lucky to snap a decent photo.

As I was delighting in watching the pair, I heard a ruckus in a nearby tree, looked up and instantly was rewarded with prime views of two low foraging Black-heads! A couple of males only, no female in sight, these boys meant business as they scrounged for caterpillars and cicadas and mantises and who knows what all from their tree top domain. They hung around for a minute or so, then vanished into the thick forest surrounding Jewel Lake. With its towering trees, bountiful canopy and dense understory, the birds have so much cover in which to hide and stay out of sight from anyone or thing intending to do them harm. Now, who would that be? Probably that little Kestrel that just flew by!

WHIZZZZIP! First time I've spotted a Kestrel at Jewel Lake! What evanescent beauty, this supreme hunting machine!

In our protected nature preserve on the doorstep of Berkeley, California, birds often are comfortable enough to just hang out in plain sight, like that Great Blue Heron across the way I spotted flying in. Attracted to the deep watery reflections from the other side of Jewel Lake, I was headed over that way and nearly botched the whole thing before stopping suddenly, a few feet away, to admire the Heron, ensconced at lake's edge amid psychedelic rippling patterns, frozen solid in a crouch stance, elongated neck curled and resting on the wide body, intense, beady eye fixed on something in the water. Eventually, tiring of his motionless stance, or unfavorable prospects, he unfurled his body, flapped his big wings and flew off in a straight low trajectory across the lake to gracefully land on an opposite sandbar to test the waters there for some - grub?

And then there's the Swainson's Thrush I first heard, then espied, in Wildcat Gorge early one morning last week. I think it was my first ever sighting of the pretty avian songster. The Gorge area is a hot zone for spotting all the rarish birds you don't normally see: Golden-crowned Kinglets, the Grosbeaks, Wilson's Warblers, Varied Thrushes, and now, finally, at long last, the Swainson's Thrush. What a vocal little creature just absolutely singing his heart out to draw attention from a suitable mate. Or maybe the little guy was just singing to unleash to the world his sweet, melodic madrigal of pure love and joy.

If you're looking for a quick, quiet get-away in the Berkeley Hills, you'll find it in the Tilden Nature Area. Here, in a pristine ecological setting, simple but stunning beauty disguises itself in pedestrian scenes, and small miracles abound but remain hidden in plain sight. I'm always adding to the many blessings counted apart from the birds to add to my ever growing Life List.

Bonus Footage:

Great Blue Heron

Warbling Vireo

Swainson's Thrush