Blakeman answers question about grizzly photo

Hi Marie,

Yesterday on Lincoln's Web site he posted some photos of Pale Male raiding a robin's nest and making off with one of the chicks. Lincoln has mentioned this behavior on his site once or twice in the past and today's grizzly (albeit natural) photos raised a question in my mind. Why would Pale Male choose to raid a robin's nest and make a meal of a scrawny chick rather than capture a plump adult pigeon or some other more satiating and satisfying prey item? Could selecting an easy, though less substantial, meal be a sign of his advancing age, or is this a common red tail behavior?

Thanks!

Robin Lynn

John Blakeman responds:

Marie,

Red-tails commonly raid robin, grackle, and other birds' nests. It has nothing to do with age. A nice plump little robin nestling is just too tempting. The effort required to acquire the morsel is a mere low-power fly-in and -out. Nothing easier for less effort.

Like any other wild predator, red-tails have no morality or ethics, only an instinctive desire to acquire food easily and frequently.

Such depredations are an important element in the learning of hunting by first-summer red-tails. These easy pickings can allow the new hawks to survive their first summer when their hunting skills aren't yet sufficient to capture fully healthy and adult prey.

Of course, this is why robins commonly produce two or three broods of three or four nestlings. Very few will ever survive to adulthood.

--John Blakeman

The fuzzy foursome and a Postscript

Four Green Heron chicks at the Upper Lobe nest - 7/14/06
Photo by Lincoln Karim

PS As soon as I can I'll post a summary of my conversations yesterday with Ward Stone of the NY State DEC, Len Soucy of the Raptor Trust, and Cal Sandfort, raptor biologist at the Peregrine Fund's Center for Birds of Prey in Boise, Idaho. Subject: Pale Male & Lola's retrieved eggs.

Press Release about Pale Male & Lola's eggs from NYC Audubon

The long-awaited press release. I'll discuss some of these findings in my next posting here. Right now let me point out the significance of the fact that the eggs were found to be "intact". This clears up the possibility that the anti-pigeon spikes damaged the eggs during any phase of incubation.

Pale Male and Lola’s Egg Analysis

On June 13^th 2006, Chris Nadareski, Director of Wildlife Studies for the NYC Department of Environmental Protection, in cooperation with the NYS Department of Environmental Conservation and building management, retrieved three intact eggs from Pale Male and Lola’s nest on Fifth Avenue. The red- tailed hawk eggs were taken for examination by DEC staff to Ward Stone, DEC’s wildlife pathologist. The examination revealed no sign of embryonic development in the eggs, which indicates the eggs never passed the early stages of development. The eggs were sent out for toxicant analysis, which found very low traces of organochlorine pesticides and PCBs, no significant levels of metals such as mercury and lead, and no anticoagulant rat and mouse poisons were found, suggesting that these chemicals did not pose a threat to the proper development of the eggs. The organochlorine and metal analyses were done by Pace Analytical Services, Inc. of Wisconsin and the rodenticides by the Illinois Department of Agriculture.

In December 2004, Pale Male and Lola’s story captured the attention of the world when the Co-op Board removed their nest. People from around the city and around the world wrote letters and emails, made phone calls, and stood out in the cold asking for the building to “bring back the nest.” NYC Audubon led the efforts of many groups and individuals in successfully advocating for the return of Pale Male and Lola’s nest spikes to the window ledge. NYSDEC, NYCDEP, and the building staff and management worked to get a new and improved nest cradle structure to address the needs of the birds and the concerns of building management.

After an unsuccessful nesting last year, the hopes of New Yorkers were high that this year would produce a new brood of nestling hawks. Despite the egg analysis, it remains unclear why the nesting pair has failed; fertility and/or weather may have played a role. It is not uncommon for raptor nests to fail occasionally after many years of success.

Energized by Pale Male and Lola and their many supporters, NYC Audubon continues to carry out its mission of bird conservation. Today, through its Lights Out NY program, building owners are turning off decorative lights to protect migrating birds. NYC Audubon’s advocacy on behalf of Pale Male and Lola has shown New Yorkers that it is essential to have an organization that protects the wild birds and wild lands of the city from neglect and threats.

New York City Audubon is a grassroots community that works for the protection of wild birds and habitat in the five boroughs, improving the quality of life for all New Yorkers.

###

First baby pix

7/12/06: Bruce Yolton got there first. Here are two pictures of the newly hatched Green Heron babies at the Upper Lobe. There are AT LEAST two chicks in the nest.

One chick...

Two chicks...
Photos by Bruce Yolton
http://www.urbanhawks.blogs.com

BioBlitz Turtles

Regina Alvarez, Central Park's Woodlands Manager, writes:

Marie,

I thought you might like to see a few photos of two species of land turtles I saw the day of the BioBlitz. The first two are of a wood turtle (Clemmys insculpta), the first wood turtle I've seen. The next two are of an Eastern box turtle (Terrapene carolina carolina). I was very excited to find a new species (new to me, at least.)

Regina

Wood Turtle



Wood Turtle


Eastern Box Turtle



Eastern Box Turtle
Photos by Regina Alvarez

The egg report hasn't come in yet

Red-tailed Hawk nest, with eggs




Sorry. I'm anxious to read it too. I'll post it as soon as it comes in.

The Central Park Moth-ers return

Ilia Underwing - partially open

Former Girlfriend -- closed
Photos by Marie Winn


The so-called Moth Tree, an English Oak that periodically oozes moth-attractive sap, is back in business. On Sunday, 7/9/06, between 8:30 and 10 pm, a host of moths in the Catocala family, beautiful creatures with cryptic forewings and dramatically colored hind wings, could be seen fluttering around its lower branches and then settling in to feast on the sap.

Not much diversity yet-- almost all the large moths were Ilia Underwings, a common species with bright orange and black hind wings. [See the list of Underwings we've seen in previous years, at end, to see what might lie ahead. And also to enjoy their names.] But there was one other species of particular interest. Also in the Catocala family, it is a little moth that used to have the charming name of Girlfriend Underwing --Catocala amica. Since that was its identification in the one and only field guide to Moths that exists in English *, by the one and only Charles V. Covell, naturally that's the name the C.P. Moth-ers have always called it. But recently Covell has had his book republished. Now in a new preface to the same old text he provides a long list of corrections he has accumulated over the years. Among them is the former Girlfriend Underwing. Covell had misidentified it. Now, alas. the glamorous Girlfriend has metamorphosed into the mundane Little-lined Underwing-- Catocala lineela. Sic transit gloria mundi.

* There is a French field guide -- Le Guide des Papillons du Quebec that includes most of the moths we see in Central Park.


The Underwings of Central Park

1. [former]Girlfriend Underwing Catocala amica

[Now] Little-lined Underwing Catocala lineela

2. Ultronia Underwing Catocala ultronia

3. Little Underwing Catocala minuta

4. Widow Underwing Catocala vidua

5. Sad Underwing Catocala maestosa

6. Yellow-gray Underwing Catocala recta

7. Tearful Underwing Catocala lacrymosa

8. White Underwing Catocala relicta

9. The Betrothed Catocala innubens

10. The Little Wife Catocala muliercula

11. Oldwife Underwing Catacola Palaeogama

12. Habilis Underwing Catocala habilis

13. Yellow-banded Underwing Catocala cerogamma

14. The Bride Catocala neogama

15. Clouded Underwing Catocala nebulosa

16. Youthful Underwing Catocala subnata

17. Ilia Underwing Catocala ilia

18. Locust Underwing Euparthenos nubilis

19. Once-married Underwing Catocala unijuga

20. The Penitent Catocala piatrix

21. The Sweetheart Catocala amatrix

22. Darling Underwing Catocala cara

FLASH --Green Herons on target

Green Heron Chicks being fed, May 30, 2005
Photo by Cal Vornberger


Here's an exciting item from ebirds via Central Park birdwatcher Rhoda Lee Bauch:

DATE: Tuesday, 11 July 2006
LOCATION: Central Park

Hurrying to a doctor's appointment on the West side, I stopped at the Green Heron nest at about 2 p.m. where Annabella Cannarella greeted me with the news that she'd just seen the adult Heron lift the front of its body up revealing a white "fluff ball". Having missed this exciting event, after my doctor's appointment I returned to the nest at about 4 p.m. Luck was with me and I saw the new chick. We can conclude that at least one egg has hatched.

P.S. Bob Levy, [of Club George fame] who has been reporting regularly on the Green Herons' progress, sent in an unrelated, but amusing note today:

Here is a pertinent quote from a New York Times article about the Space Shuttle (New Scrutiny for Every Speck on the Shuttle, July 11). Unfortunately it does not mention if this was a “first” though I would guess it wasn’t. Still it goes to show us that even NASA has to pay attention to birds, or bird by-products, some of the time:


"They also pondered an octopus-shape black mark on the leading edge of the right wing that turned out to be soot from the craft’s small rockets and a suspicious white mark that appeared to have a black center that turned out not to be a dangerous ding, but dung. Or, more precisely, bird droppings."

Skimmer sleuthing

Black Skimmer
Photo by Cal Vornberger
http://www.calvorn.com


Bob Levy, the author of Club George: The Diary of a Central Park Birdwatcher [St. Martin's Press], posted the following report on the birding newsletter ebirds

Location: Central Park
Date: July 9, 2006
Location: Central Park
Reporter: Bob Levy

Sightings of the Black Skimmer at Turtle Pond in Central Park have been fewer and sporadic. Widely held speculation is that the recent accumulation of Duckweed on the pond's surface has discouraged the skimmers from skimming there. I have myself noticed that the skimmers do not come or remain briefly if the duckweed covers a large portion of the pond. This made me wonder if I would profit by looking for them elsewhere.

On Sunday evening I went to Bow Bridge and at about 8:45PM I saw one Black Skimmer. A few minutes later there was a second. While the light held out I and others watched the two skimmers go back and forth under Bow Bridge. It was especially nice to be able to look straight down and see the birds glide directly below us.

It got too dark to see them so I gave Turtle Pond another try. There, at about 9:30 PM a very vocal Black Skimmer arrived. It only worked the areas that were relatively free of Duckweed but remained only about ten minutes. I hope you get to see them too but of course bring a friend or two or more if you are going to stay after dark.

It's tomorrow -- Neil Tyson on Manhattan-henge

MANHATTAN-HENGE

What will future civilizations think of Manhattan Island when they dig it up and find a carefully laid out network of streets and avenues? Surely the grid would be presumed to have astronomical significance, just as we have found for the pre-historic circle of large vertical rocks known as Stonehenge, in the Salisbury Plain of England. For Stonehenge, the special day is the summer solstice, when the Sun rose in perfect alignment with several of the stones, signaling the chage of season.

For Manhattan, a place where the evening matters more than the morning, that special day comes on July 12; one of only two occasions in the year when the Sun sets in exact alignment with the Manhattan grid, fully illuminating every single cross-street for the last fifteen minutes of daylight. The other occasion is May 28th. Had Manhattan's grid been perfectly aligned with the geographic north- south line, then our special day would be the Spring equinox, and if we so designated, the Autumn equinox -- the only two days on the calendar when the Sun rises due East and sets due West. But Manhattan is rotated 30 degrees east from geographic north, shifting the days of alignment elsewhere into the calendar. Upon studying
American culture, and what is important to it, future anthropologists might credit the Manhattan alignments to cosmic signs of Memorial Day and, of course, the All-Star break. War and Baseball.

Because Manhattan is so small (13 mile long) compared with Earth's distance to the Sun (about 93 million miles), the Sun's rays are essentially parallel by the time they reach Manhattan, allowing the Sun to be seen on all cross streets simultaneously, provided you have a clear view to the New Jersey horizon. Some major streets cross the entire island from river to river without obstruction, including 14th, 23rd, 34th, and 42nd streets. While the July 12 sunset qualifies as the exact day for this auspicious moment, the surrounding days will also work, as the point of sunset migrates slowly south from day to day along the horizon, bringing with it ever-shortening daylight hours.

Sunset on Manhattan-henge begins at 8:20PM, at a cross-street near you.

As always, keep looking up,

-Neil deGrasse Tyson

Department of Astrophysics
& Director, Hayden Planetarium
American Museum of Natural History
Central Park West at 79th Street
New York, NY 10024
http://research.amnh.org/users/tyson

Coming very very soon - info about Pale Male & Lola's eggs

Just got an e-mail from Ygal Gelb at the New York City Audubon Society saying that they're about to send out a press release about the report from Ward Stone re Pale Male and Lola's eggs. . I don't know how detailed the report is going to be, but here's what I know in broad outline:

1. As I've already written here a few weeks ago, according to the first analysis there was no embryonic material discernible in any of the three eggs retrieved from the nest. Now with the full report about to be available I'll be curious to find out if their tests indicate whether the egg was ever fertilized, or whether any signs of fertilization might have been eradicated by either extreme cold [if the eggs were chilled] or by any other factor. This could clarify whether the problem was due to Pale Male's infertility [due to age], or something to do with the new structure installed on the ledge in January 2005 after the nest-removal crisis was resolved.

Back in 1994, when Ward Stone analyzed a fragment of Pale Male's egg from the nest removed that year, the report was vague about whether the egg was fertilized or not. It simply said that there was no embryonic material found. In a long phone conversation with me Ward Stone then raised the possibility that the nest failed because of Pale Male's immaturity. I always wondered why there wasn't a test that could tell with certainty whether the egg had been fertilized or not , sort of like a pregnancy test for women , using the presence or absence of certain hormones. Perhaps now such a test is available.


2. Based on further toxicology tests there seems to be no sign of any toxic substance -- pesticide, rodenticide, etc. in the eggs. This is what John Blakeman predicted, if you recall.

I'll publish here ALL details as soon as I receive them. That's a promise.

The return of Manhattanhenge

A photograph of "Manhattanhenge" as seen from 34th street. The photo is from Dr. Neil deGrasse Tyson, director of the Planetarium in New York.

http://research.amnh.org/users/tyson/images/
publications/ManhattanSunset.jpg

Did you miss Manhattanhenge on June 21st? You have one last chance this year to see the sun setting exactly at the western end of every one of Manhattan's streets that run from east to west [not, of course, the Avenues that run from north to south]. It will happen again next Wednesday, July 12th:

Tom Clabough, an amateur astronomer who is often to be found at the northeast corner of Central Park's Great Lawn, ready to point out sky happenings to all interested passers-by, sends the following note of explanation:

The red line represents the path of the Sun during summer solstice. The green, winter solstice, and the blue, both spring and fall equinoxes. Note how in summer the Sun rides high in the southern sky as it rises and sets NORTH of the east-west line. And in winter, the Sun rides low in the southern sky rising and setting SOUTH of the east-west line (true east-west). During the two equinoxes the Sun is at an intermediate inclination, rising and setting precisely east and west.

Now, recall that the northerly aligned avenues of Manhattan are actually skewed about 30 degrees to the east of true north, as the easterly streets are skewed ~30 degrees south of true east. If the street grid were in line with the compass, the "stone-henge effect" would occur at the spring and fall equinoxes, since this is when the Sun rises and sets due east and due west. However, since the grid is rotated ~30 degrees, the effect happens to occur 22 days before reaching summer solstice, and again 22 days on the return from summer solstice, summer solstice being the Sun's northern most rising and setting points.

In the event the diagram did not appear, here is a direct link to it:

http://www-spof.gsfc.nasa.gov/stargaze/
Sfigs/Sunpath2.gif