Saturday, December 17, 2005

Grackles on the move

Pear trees at south end of Grand Army Plaza with Pulizer Fountain [statue of Pomona on top]


Pear trees at north end of Grand Army Plaza
with statue of William Tecumseh Sherman










There are two symmetrical semi-circles of pear trees at the Grand Army Plaza just east of the Plaza Hotel, one at the north end surrounding a statue of General William Tecumseh Sherman, and the other at the south end, surrounding the Pulitzer Fountain.

In October, when I first started observing the huge flocks of grackles and starlings flying out of Central Park every evening, the entire flock roosted for the night in the southern semi-circle, at the fountain. Those ten pear trees hosted what I calculated to be more than a thousand birds each night.

A few weeks ago, when most of Central Park's trees had lost their leaves,
the Bradford Callery Pear trees finally began to lose their green color. The leaves, however, now brownish- bronze, hung on tenaciously. Last week the trees were evidently getting thinner. For some reason, however, the trees near the Sherman statue seemed to be hanging on to their leaves longer than the Pulizer Fountain trees.

Probably because there was more cover there, a few birds began to roost at the northern end's trees. At about that time the flock became a bit smaller.
But most of the flock continued to roost at the Fountain trees.

Two nights ago the trees by the Pulizer Fountain were almost completely bare; just a few small, shriveled up brown leaves remained. I was amazed to see small bunches of Grackles -- the starlings seem to have gone elsewhere -- still roosting for the night on those bare trees, about 50 birds, I'd guess. They were very conspicuous there, as you may imagine, especially with their backdrop of the lighted windows of Bergdorf Goodman's on 58th Street and Fifth Avenue. That night many, many more birds, perhaps 150, roosted at the north end trees, the ones surrounding the Sherman statue.

Where is the rest of the flock? I'd say they've finally headed south.

According to that authoritative source, The Birds of North America, published by the Cornell Lab of Ornithology and the American Ornithologists' Union, Fall Migration for grackles "can begin in August-September but typically peaks late October-early November and is usually completed by early December." Well, today is December 16th and at least part of the flock is still here. The larger part of it were still here in early December, though they seem to have finally gone. So much for authoritative sources!

PS At 7:30 last night [12/16/05] there were still about 50 grackles roosting out in the open on the bare trees surrounding the Pulitzer Fountain. Since there were still quite a few leaves on the pear trees at the north end of the plaza, [around the statue of Sherman,] I couldn't really see how many birds were sleeping there. I could make out many dark shapes, but wasn't sure whether some of them weren't birds. Shining my bright flashlight up into the crown of the tree only made the bird shapes recede into the leaves, for some reason.

Friday, December 16, 2005

When in doubt, retreat

Gray Screech Owl menaced by Black-capped Chickadee



Come on out, you coward.

Photos by Cal Vornberger
December 12, 2005

Thursday, December 15, 2005

Blakeman on Pale Male & Lola's prospects this year

Here's website correspondent Mai Stewart 's letter to John Blakeman and his response:
Hi John,
I've been noticing the gradually increasing hawk activity (as reported on the websites) -- and had a question re the state of the nest.
You may recall that a few weeks ago Marie posted on her website 2 pictures of the nest -- one was of the nest before it was destroyed and subsequently rebuilt, and the other pix was (I think) of the nest as it was a few weeks ago, including the fact that the hawks have been slowly but diligently working to add new material to build it up.
A couple questions have come to mind, following this and other reports (as well as Donna Brown's, yesterday) -- first, altho the nest looked better a few weeks ago than last winter, when the eggs failed to survive, it still looked a little skimpy to me compared to the way it had looked just before it was destroyed, when, the previous spring, the eggs had survived and chicks had been born successfully. So my worry is, even tho the nest is getting bigger + better, will it be sufficient this year to cover the pigeon spikes and enable the new eggs to survive and bear chicks successfully?
And, I've been really amazed at the bonding between PM + Lola, and their continued attention to this nest -- even tho things didn't work out last spring -- is this usual in RTs?? Do they mate for life -- at least as long as one of the pair survives -- are they generally monogamous, and so faithful to each other after their first bonding and breeding of chicks?
I look forward to your thoughts!
Thank you, as always,
Mai Stewart
Mai,
I, too, am a bit concerned about the state of the 927 nest. It's really good to see that Pale Male and Lola are incidentally bringing new twigs to the nest. But I fear that once again, they may fail to get the bottom of the nest depression sufficiently above the protruding pigeon prongs. The issue is this.
Last year the birds failed to create a nest deep enough to suspend the eggs above the prongs. The eggs never hatched, either because they were punctured at the end of incubation when the shells become thinned, or perhaps because the metal of prongs conducted heat away from the eggs. Because the adults were experienced, nesting should have succeeded. The low stature of the nest seems to have been a major factor. And it's still too low.
Here's what I'd want to see this year. For the next few weeks, until things really pick up in January's increasing day lengths and elevated nesting hormones in the adults, there is not likely to be any substantial nest activity. The insertion of a few scattered twigs each day right now is just pro forma stuff, a result of the abundant food the birds have. Out here in wild rural areas, winter red-tails seldom, if ever, spend time and energy with nest twigs. Food is harder to find and capture than in Central Park. We don't have succulent rats scampering around, as apparently is the case in portions of Central Park. In winter, our rural birds have to spend most of their waking hours sitting and hunting the much smaller meadow voles. They don't waste time and effort on the nest just yet. The fact that CP red-tails are playing on the nest indicates the prime availability of food there.
But let's see what happens to the nest in January and February. I fear that the worst could recur, that the birds would once again build the nest only to slightly above the prongs. As I've mentioned before, it appears to me that red-tails build their nests only until it feels rigid. They don't build it to any predetermined height or thickness. They just keep plugging in sticks until it finally feels solid when then squat down on the nest and flail it a bit with their tucked-under legs. When the stick pile stops shaking, when the pile feels compact and in place, the birds think nest building is done. It's then just a matter of bring in the loose lining materials.
If this happens again, and I fear that it might, the new eggs won't be much higher above the prongs than they were last year, with the likelihood of the same result.
The better result would be if the birds somehow get the pile of twigs above the prongs before serious nest building begins in late January and into February. If that happens, the elevated twig pile will not be supported by the prongs beneath. As the birds sit on the taller nest in January and February, their instinctive leg motions will tend to spread out the new loose pile. That will be a powerful prompt to bring in lots of new sticks, to create a more typical red-tail nest.
If the birds can get the sticks above the prongs early in the nesting season, they will be prompted to complete the structure in a typical way. Red-tail nests out here in Ohio oak trees are typically 14 to 24 inches deep. Fourteen inches of sticks at the 927 nest would keep the eggs above the prongs.
So, let's see how deep the pair builds this year's nest. If in February it's still just above the prongs like last year, things will likely go wrong again. If the nest takes on a more typical bushel basket form, things should go well.
It's still too early to worry about this. As before, we'll just have to watch what the hawks decide to do.
You asked if the bonding, the "pair love," is normal, given all the difficulties they've encountered. Yes, it is. Red-tails generally mate for life. Pale Male and Lola don't fall asleep each night lamenting their failed efforts last spring. They just go about their activities prompted by genes and instinctive behaviors, which for this species (and most other raptors) causes strong pair bonding, not matter what else happens.
As romantic or poetic as it might be, to see the pair bonding of this pair as an exemplary model for humans, is a biological stretch. They are bonded because this noncompetitive, mutually-helpful hunting and nesting arrangement works best. Birds that didn't have these behaviors in the past encountered all sorts of difficulties and they either died off, or at least had few offspring to pass on their peculiar genes.
It's classic natural selection, the survival of the "fittest." For me, this is a great natural spectacle in Central Park. Astute observers, like yourself, are able to closely observe the forces and events that define the lives of these great predators.
The new nesting season is beginning. Keep me posted.
Sincerely,

John A. Blakeman

Wednesday, December 14, 2005

Early Birders in the cold and dark get ready for the Christmas Count

Rusty Blackbird - Photo by Lloyd Spitalnik

At 7:00 a.m. yesterday, in the bitter cold [well under 20 degrees] and in the semi-darkness [12 minutes before sunrise] five bundled-up birdwatchers [Alice, Karen, Joyce, Naomi and I] met as usual for the Wednesday morning birdwalk. The Stalwarts. Handwarmers and toewarmers were used by all.

In fact it was a beautiful day, clear blue sky, and a beautiful, puffy sunrise cloud tinged with orange floating upward to the north of the Carlyle shortly after 7. Our star birds were: an Eastern Towhee near Strawberry Fields, several flocks of Cedar Waxwings, and, at 8:45, just before we went to the Boathouse for our well-deserved hot drink, a Rusty Blackbird in the Oven. This would be a nice bird to have on the Christmas Count next Sunday,

[I'll report on that next Week. I'm joining a great team surveying the wild northwest quadrant of the park -- a number of Early Birders, and some heavy hitter-birdwatchers. We hope to come up with some spectacular birds. Sorry, but the competitive spirit is high! Don't forget that the first Christmas Count around the turn of the last century was devised to replace a traditional Christmas Hunt. Though the hunting spirit lives on in the latter-day version of this, at least nobody kills birds in these Audubon sponsored events.]

Owl romance continues

Photo by Lloyd Spitalnik
DATE: Tuesday, 13 December 2005
LOCATION: Central Park
OBSERVER: Bob Levy

Here’s an update of the seemingly “on-again-off-again” relationship between the red and gray morph Eastern Screech-Owls in Central Park. Today the relationship was most definitely on again. After sunset I positioned myself opposite the gray morph’s tree cavity. At 4:56 PM the gray morph popped up into the opening. Instead of first scouting the surrounding area before exiting, as I expected it to do, this screech-owl wasted no time placing one foot on the rim
of the entrance and then the second. I took this to mean it would be making a quick exit. I readied myself so I might not miss the bird’s flight. Instead of seeing the gray morph bolt out of the hole a second screech-owl popped into view. It was the red morph Eastern Screech-Owl. It nestled a little below the
other bird with its head pressed against the other bird’s flank. For a few seconds the two owls sat motionlessly in this pose and I thought to myself, “They really do make a nice couple.” About thirty seconds passed while they held this pose, then the gray morph shot out of the cavity. I assumed it would quickly be gone but the owl perched about fifteen feet away, almost directly opposite my position. The red-morph made its exit too but this owl disappeared into the trees to the west. Meanwhile the gray morph stayed put, looking around but never in my direction. Less than a minute passed when the red morph made two calls. This was all the gray morph needed to hear and the bird darted in the direction of the sounds. I followed but could find neither bird. These two birds are giving Central Park birders an education in owl relationships. A birder never knows when they might be seen together or apart. They contrast with another pair not very far away that are consistently seen in each others company.

Lloyd's photo of the Gray-morph Screech-owl was taken on November 30, 2005, at its roost-hole near the rowboat lake.

Tuesday, December 13, 2005

Donna Brown returns: minute by minute report

Pale Male and Mom I [with band] -- 1996
Photo by Charles Kennedy


Pale Male and Lola 12/12/05

I arrived at the Hawk Bench at 2:39PM today and before I could even start to set the scope up, Pale Male and Lola appeared soaring above the Oreo building. One hawk flying counterclockwise and the other in clockwise circles.
At 2:41 Lola landed on the chimney of the Oreo and Pale Male headed out for Madison Avenue. A moment later he appeared very briefly between two Madison Avenue buildings in a dive. Lola continued to face the Bench sitting in what we assume is a warm draft from the chimney.
By 3:02 Lola had disappeared from the Oreo Chimney and at 3:03 Pale Male appeared above Fifth Avenue from the north. He circled his way south over the buildings.
3:06, Pale Male lands on the railing of Linda 1, facing out, breeze ruffling breast feathers.
3:12 The sun comes out and the freshness of Pale Male's new feathers, from his latest molt, is quite apparent, they gleam. His belly band is more noticable, as the color is deeper than in late summer. He surveys the area.
3:20 Pale Male visually tracks a flock of pigeons as they fly by. But continues to sit. His crop is very full.
3:31 Pale Male up and circling to the north end of the Model Boat Pond. Circles above Octagon, disappears behind it and then to the Oreo antenna. He faces the Ramble.
3:37 Pale Male up, circles above Oreo, disappears behind it, appears to the west side, and into tree. Works at twig until he clips it, then up circling and to nest. Places twig, looks down at nest, walks, pause, rearranges twig, then up and returns circling to Oreo Antenna. Faces Ramble.
Katherine reports that for three nights running Pale Male has roosted in his favorite tree at the foot of Pilgrim Hill. The one he very often uses while Lola sits the nest.
As the hawks slowly left the nest in stages last season , they are now slowly in the reverse returning to it. The circle continues.
Donna Browne


Fickle Owls?

Gray-phase Screech Owl in roost-hole near rowboat lake
Sunday, 12/11/05
Bruce Yolton writes:
The news from Sunday was that the Red and the Gray Eastern Screech Owls were back to their separate locations. Guess it was a one night stand.
[See post of two days ago ]

Red-phase Screech Owl in roost-hole near meadow edge
Sunday, 12/11/05

Photos by Bruce Yolton

Monday, December 12, 2005

Lola and others caught [on film] last Saturday

Red-tailed Hawk [Lola] at the Locust Grove

Red-tailed Hawk [Lola] on the Beresford

Bruce Yolton is a relatively new Central Park birder. On his website - www.yolton.com -- he describes the circumstances that started him off learning about and phographing Central Park birds. [It had to do with Christo's Gates]. On Saturday, a few hours after we observed the Screech-Owl fly-out, he sent me the pictures I posted that day.

Above and below are some other birds he saw and photographed earlier that day. The photos are followed by his complete list of sightings that afternoo
n,.

Brown Thrasher


Red-breasted Nuthatch

White-throated Sparrow

Tufted Titmouse

Northern Cardinal

Eastern Screech-Owl in London Plane-tree Roost Hole
some time before that evening's fly-out

All photos by Bruce Yolton

Here is the annotated list Bruce sent me:


A cold winter afternoon in Central Park.

Photographed:
Brown Thrasher, Pinetum
Red-breasted Nuthatch (new bird!), Pinetum
White-throated Sparrow, Pinetum
Tufted Titmouse, Pinetum
Northern Cardinal, West of Pinetum
Gray Squirrel, Southbound West Drive around 84th
Rudy Ducks, Canadian Geese, and Gulls, Reservoir
Cooper's Hawk, Locust Grove
Red-tailed Hawk, Beresford
Red-tailed Hawk, Locust Grove (landed near the Cooper's Hawk, almost to say this is my spot)
Red-tailed Hawk, A block north of the Beresford
Red-tailed Hawk, A block north of the Beresford
Eastern Screech Owl, West Side 70s

Other Birds:
Great Blue Heron
Mallard Duck
Bufflehead
White-breasted Nuthatch
Rock Pigeon
Blue Jay
Common Grackle
House Sparrow




Sunday, December 11, 2005

Red Screech finds a friend

Red Screech Owl in his/her own roost hole - 12/ 7/05
Photo by Lincoln Karim


The grey-phase Owl at his own roost hole - 11/ 30/05
Photo by Cal Vornberger



The following hot item appeared on e-birds yesterday:

Today (Saturday) the red phase screech owl was not in the black locust where it usually is, but the gray phase was present in the sycamore/London plane tree. * Then, while we were watching the gray, the red phase poked its head up from the same hole! The gray phase flew out at 4:55. He perched nearby for a few minutes as though waiting for the red, but then flew away. The red phase flew out about ten minutes later.

Ken Hicks

*Note from Marie: The two roost holes are both in the Ramble, but not by any means close to each other. If you're wondering why I'm not more specific about the owls' locations, I've posted the explanation before and will briefly repeat: Revealing owl locations violates Birders' Etiquette. Since owls , unlike song birds, generally remain in the same location all day -- sleeping -- they are vulnerable to predation or mischief. If you are a birder in Central Park, other birders will happily show you an owl's location. But for the birds' safety, the information must not go out on a post read by the general public.