Saturday, January 27, 2007

Are the swans OK?

Mute Swan on ice at Harlem Meer, 2/15/06
photo by Cal Vornberger [http://www.calvorn.com]


On a day when the temperature in Central Park dipped to 8 degrees, Gena Palumbo of NYC writes:


I am worried about the mute swans on the Central Park lake in this cold weather. Will they be ok?

Here's my answer:

Dear Gena,

Mute swans have overwintered in Central Park for many years. Their problem is never that they get too cold when the temperature drops. Don't forget their magnificent down jackets, and their waterproofing, to say nothing of their various means of homeostatic thermoregulation. The only thing that would affect their survival is the lack of open water in case everything freezes over completely. They need some open water to survive. This is true for the overwintering ducks as well.

The Lake in Central Park rarely freezes over completely. There is almost always some open water near or under Balcony Bridge on the Lake, for example. Often when the Lake seems frozen you'll find great numbers of ducks and the swans in that area. However, if the Lake and other waterbodies were to completely freeze, thus affecting the birds' food supply, don't forget their wings. They'll fly elsewhere in search of open water.

These are very strong and hardy birds with a good layer of down to protect them from cold. And they are powerful flyers in case of an extreme frost. So while I can't guarantee anything, obviously, I'd say: Not to worry.

Cheers,

Marie


posted by Marie Winn @ 1/27/2007 11:30:00 AM  

Friday, January 26, 2007

Harbingers of spring

Tufted Titmouse - photo by Bruce Yolton


I asked Jack Meyer, daily Central Park bird monitor and leader of bird walks, to let me know the first time he hears a real spring bird song. On Wednesday he wrote:

This morning by the Riviera there was a Red-winged Blackbird practicing a few gurgles. Just one phrase out of the song.
Jack

and

Though winter weather had set in, on the same morning, at 7:30, the Early Birders heard a Tufterd Titmouse singing its spring breeding song--- Pe-ter, Pe-ter!

Moral: Nature's seasons are not the same as calendar seasons

posted by Marie Winn @ 1/26/2007 10:30:00 AM  

Wednesday, January 24, 2007

Robofalcons


In regard to a posting here on January 19th and a reply on Jan. 20 regarding a company with a pigeon-control problem, Steve Watson of Pasadena, California [some of you may remember his nesting kestrels Dash and Lilli] sent in the following suggestion:

Perhaps your correspondent with the pigeon problem needs a radio-controlled ornithopter! Yep, they do make them...and some places like airports have used them to try and scare off birds. Here's a video of a rather large version of one...with a link for your readers :)

http://www.intercept-technologies.com/products.html

Stephen H. Watson

posted by Marie Winn @ 1/24/2007 10:27:00 AM  

Tuesday, January 23, 2007

Their thoughts are turning

Photo by Lincoln Karim

Remember "In the spring a young man's fancy lightly turns to thoughts of love"? Well, it's certainly winter now [finally!], but in Central Park a young [or not so young] raccoon's fancy is already turning [and not so lightly] to thoughts of love. In fact, as Rebekah Creshkoff's note [below] suggests in its final comment, January is usually the month raccoons start their families.

 Rebekah, by the way, is a long-time member of the Central Park birding community. Among her many distinctions she is the Founder of NYC Audubon's valuable program Project Safe Flight. [You may remember her from Red-tails in Love.]


Tonight [1/22/07] as I was biking home through the park, I saw a couple of raccoons coupling. It was after dark, 7:00 p.m. or so. They were in a tree along the ramp between the zoo and the skating rink, where hiphop-type music was blaring. Tree is the first south of streetlight E6301, along the same "median strip."
First saw male run W across ramp and climb straight up the tree (this is all silhouetted). Kept observing, and after a while another form materialized. The second coon was much smaller. They came together, would part, scamper along a different bough. She didn't seem terribly interested to me, but eventually I heard noises -- little barks, mewings, and squeaks -- coming from their direction -- enough to attract the notice of a couple of dogwalkers.

This is my second raccoon sex sighting. The first was one Jan. morning, in 2003 or '04.


posted by Marie Winn @ 1/23/2007 09:05:00 AM  

Sunday, January 21, 2007

Moon, stars and planets: from the archives

Crescent Moon & Venus, setting over Central Park south - 1/20/07
Photo by Lincoln Karim ---[click on photo to enlarge and see details]

When I saw Lincoln's photo today on palemale.com it reminded me of a time two years ago when I saw a beautiful crescent moon and Venus setting over the same buildings. That time they were joined by another planet as well, Jupiter. Below , my report of that planetary conjunction with a note about seeing Venus in broad daylight:

Utterly impossible and incredible

During the last week of August a few years ago, I received an e-mail from one of Central Park's amateur astronomers -- the star guys, as I think of them. It alerted me to an imminent astronomical event: the planets Venus and Jupiter would both be setting a little after sunset on September 1st . In this conjunction of planets, as it is called, the two planets would seem so close that they’d span the width of your index finger if you extended it at arm’s length. This was exactly the sort of picturesque phenomenon the star guys love to point out to the passing world. Then on September 6th, the e-mail noted, the planets would be joined by a lovely crescent moon. I planned to be there both nights.

The meeting place was the north side of the Great Lawn. We arrived at 6:30. By then Charlie Ridgway and Tom Clabough, two of the astronomy Regulars, had already set up a large telescope and a pair of 16 power binoculars mounted on a tripod. Their chosen viewing spot at the edge of one of the largest open spaces in Central Park provided a perfect stage for the sky spectacle about to begin. The planet Venus began the magical show even before twilight set in. Using distinctive tree outlines and skyline buildings as reference points Tom Clabough pointed out a pinpoint of light in the southwestern sky. It was Venus, visible in broad daylight without the help of a telescope or binoculars. I found it easily with Tom’s guidance but I doubt I would have found it on my own. Of course the planet was much more brilliant when I proceeded to view it through the telescope— now it resembled a little sun. But looking up and seeing Venus in the daytime sky is strangely thrilling.

Actually it’s not a once-in-a-lifetime thing to see Venus by day. I’d seen it in a daytime appearance earlier that year, at 3:50 p.m on June 23rd to be exact. Ben Cacace pointed it out to me that time. Ben happens to be a star guy, hawkwatcher and birdwatcher all in one person.

As night fell on September 1, the day of the conjunction, the second planet became visible to the northwest of the first at 7:10 pm. By then you could see both Venus and Jupiter in a single binocular view and they seemed to be getting closer and closer. Just before sunset, the horizon already taking on a burning reddish-orange glow, I held out my arm and peered at my extended index finger. Sure enough the two planets were obscured by the width of my finger. They were only 1.2 degrees apart, Charlie told me.
Of course this did not mean that they were actually close to earth in distance, he noted. In reality Venus was 105 million miles from earth that night, and Jupiter 576 million miles.

With the Pinetum and the Reservoir behind us we were facing the park’s southern border and the enchanted night skyline of Central Park South. The line-up from east to west went like this: at Fifth Avenue the Plaza Hotel, [now selling astronomically expensive condominiums instead of renting exorbitantly expensive hotel rooms]; the Park Lane; the Ritz Carlton; Essex House with its huge red rooftop sign; the gilded ziggurat of Trump-Parc where Junior, [quite possibly Pale Male’s offspring] and his mate Charlotte, [named in memory of Charles Kennedy] once raised two healthy redtail chicks; the copper mansard roof of the Hampshire House; finally, at the western end, the twin towers of the Time-Warner Building. The man-made lights glittered. The planets outshone them that night.

Five days later, on September 6th, the planets were joined by the slenderest of crescent moons. “Imagine the astrological significance that the ancients might have ascribed to a celestial summit meeting such as this,” the Hayden Planetarium’s Joe Rao wrote about the threesome of planets and moon. His comment appeared on Space.com, a widely read astronomy website.

In honor of the special occasion five amateur astronomers set up telescopes at the usual place on the Great Lawn: Charlie and Tom, joined by Peter Tagatac, Kin Lee and Tom McIntyre.. Three regular Central Park night observers, Nick Wagerik, Naomi Machado, and I joined the astronomers at their telescopes as darkness fell. Venus was already in view in the southwest. By 7:00 pm the crescent moon was visible, a slender D-shaped curve—waxing. Jupiter appeared just before sunset, and through a telescope we could see its equatorial bands and four of its moons. In the course of five days the two planets had separated by a few more degrees. Even an outstretched hand in a baseball glove wouldn’t have managed to blot both of them out that night. Jupiter and Venus flanked the moon, two glowing eyes to the moon’s curving nose below.

The sun set at 7:20, the moon at 8:35, Jupiter ten minutes later, and Venus a few minutes after that. . They all set in the west, of course. I used to be a little fuzzy about that fact. Like the sun, everything rises in the east and sets in the west—the moon, the planets, the comets, the stars—the whole shebang. On the other hand nothing actually rises and sets at all---it’s an illusion. We see it that way because we’re revolving around the sun while rotating on an elliptical axis.

The planets were setting but still visible when the first stars appeared in the rapidly darkening sky. As each became visible the star guys told me their names. Spica was first, then Vega high overhead. Altair next. Then Deneb, identified by Peter or Kin or one of the others – it was getting too dark to see. That completed the Great Triangle of the summer sky. After that the stars came out too fast to note. As in the poem* they marched around the ancient track, rank on rank, while we mortals below watched with awe and wonder.

###

Postscript: A few days later, my friend Roger gave me a book called Myth and Meaning, by the French anthropologist Claude Levi-Strauss “There’s something about seeing Venus in the daytime that might interest you,” he said. My curiosity piqued, I went through the book page by page [it was a slim volume] until I found the reference. I did find it interesting—Roger was right. Here’s the passage:

“Today we use less …of our mental capacity than we did in the past; …, When I was writing my first version of Mythologiques [Introduction to a science of Mythology] I was confronted with a problem that to me was extremely mysterious. It seems that there was a particular tribe which was able to see the planet Venus in full daylight, something that to me would be utterly impossible and incredible.”


 I’m planning to send the father of structural anthropology a letter one of these days describing our activity at the Great Lawn just before sunset on the evening of September 1st, 2005 and on other occasions before and after. Levi-Strauss is quite old now – ninety-eight, I’ve heard. I think it’s time he knew that in the 21st century there’s a particular tribe in Central Park performing the same utterly impossible and incredible feats of sensory perception on a regular basis.

*Lucifer in Starlight by George Meredith

posted by Marie Winn @ 1/21/2007 02:19:00 PM  

From the archives of the Fifth Avenue hawks

Happier times -- April, 2002, Lola's first chicks, two weeks old
Photo by Lincoln Karim


The geriatric theory

In June, 2006, when Pale Male and Lola’s three eggs were scooped from the nest after the second year of failure, they were found to be intact. When Ward Stone, the DEC wildlife pathologist, examined the contents he found no signs of fetal development within. The geriatric theory immediately moved into first place on the list of suspects. Here’s how the argument went:

Pale Male is now 15 years old. He’s a geriatric hawk, too old to fertilize Lola's eggs. The eggs didn't hatch because they were not fertilized.

I hated this theory. Why should an older hawk be a too-old hawk, I thought, taking it a bit personally. Pale Male didn’t act like a geriatric hawk at all. What about those magnificent performances on rooftops, chimneys and TV antennas last February and March, witnessed by hundreds of passers-by at the Model-boat Pond?

This brings up a linguistic bone of contention. The hawkwatchers kept using the word “mating” for the sex act, though John Blakeman, the Ohio hawk expert, objected to that usage. Mating only means renewing the pair bond, he reminded the hawkwatchers in letters I dutifully made public. Blakeman urged us to use the proper, scientific word for the sex act – “copulation”—just as he hoped we would substitute the falconers’ term “eyass” for chick or baby hawk. Much more scientific, he said, sounding like a high school biology teacher, which of course he had been for many years. The hawkwatchers longed to be scientific. But most of us didn’t like the word eyass, too close to jackass, somehow. As for the “C” word, we just couldn’t say it. It sounded dirty.

But whatever it was that our hawk hero was doing up there with Lola, everyone agreed that he hadn’t shown a jot of diminished vigor while doing it. Pale Male a geriatric hawk? Baloney.

Shortly after the first post-removal-crisis nest failure I started getting letters advancing the geriatric theory. The next year when the nest failed again I received twice as many. I sent them on to John Blakeman for comment and received a response blasting the geriatric theory:

Marie:

Aging males of most vertebrates produce sperm of reduced viability. But I doubt that this is presently a factor here. First, the pair was seen to copulate profusely before eggs were laid. There is every reason to believe that the eggs were fertile and viable. They have been in the past, and there is no evidence that Pale Male's spermatozoa failed to successfully wiggle their ways to Lola's awaiting oocytes.

A 14- or 15-year old red-tail is merely mature, not geriatric. Pale Male continued to hunt, feed, nest-build, and conduct all of the other functions of his life with full alacrity. I see no evidence to suggest that our man doesn't have it any more. I believe there are a number of reports of birds of Pale Male's age reproducing successfully in the wild. I personally knew of one…

When Pale Male begins to age out, I think other things will first become evident. He's likely to be less active in hormone-driven nesting behaviors in January and February. He's likely to spend most of his reduced energies merely hunting, not in breaking off twigs and carrying them to the nest. He's less likely to ascend and engage in courtship dives.

It's possible that some January Pale Male will just disappear, with a new young male in his place. Our patriarch might even elect then to remain in Central Park, but take no role in mating, copulation, nesting, or brood-raising. He may retire from the duties of fatherhood and while away his remaining days merely hunting for himself.

But I wouldn't count on any of this happening soon. Our man has another three or four years, at least, I think, before age starts to slow him down. Right now, he's the High Patriarch of Central Park red-tails, with no observed diminution of his earned high repute. His spermatozoa still swim with vigor, I'm sure. Nothing else of his has diminished.

Blakeman’s argument seemed unassailable, but I needed more ammunition I wondered if Ward Stone might have an opinion about Pale Male’s fertility, and decided to call him up. It turns out the DEC wildlife pathologist did not buy the geriatric theory either:

"Here's my guess. With humans we worry a lot about when sexual activity is in decline, as you can see with Viagra and that sort of thing.

My experience with wildlife over all these years is that they really remain capable of reproduction for a very long period of time. If you look at bird records you don't see a big fall-off in fertility. You find a lot of birds, a lot of raptors able to reproduce until they're quite old..

Pale Male is somewhere around 15. Now that's not real old. I have a record of a 27-year-old redtail female who was hit by a car right near where I grew up in Columbia County. Her ovaries were in great shape and it was clear that she had laid eggs that same season. And I've got a male who was 17 or so whose organs were moderately enlarged -- everything looked good

There's no reason to believe that Pale Male is ancient, no reason to conclude there's a reproductive problem . I'd call him a regular middle-aged male.

posted by Marie Winn @ 1/21/2007 07:15:00 AM