Saturday, May 12, 2007

PM and Lola update

The egg retrieval is on the schedule at last. I've heard from someone at DEC who gave me that information. It will be done soon and we hope it will be in time for the microscopic analysis we've been hoping for, the one revealing if the eggs were fertilized or not.

I'll report here as soon as I hear any news.

PS A large percentage of Central Park's hawkwatchers support the idea of egg retrieval even before the hawks abandon the nest. Nobody relishes the idea of disturbing the birds even for the brief time the procedure will take. But all hawk experts assure us that it causes no harm to the birds, only brief stress. Meanwhile it might lead to action that could help Pale Male & Lola nest successfully next year.

One hawkwatcher, however, wrote me: Haven’t we humans done enough to them, what with tearing down the old nest and putting up a cradle? Is our need to know so great that we’ll put these hawks we’re supposed to love through additional stress? Why can’t we just let them be?

My answer is: No, we haven't done enough. If we have made a mistake [or mistakenly supported a mistake made by others] we must now do our best to help undo it. Finding out if the eggs were fertilized, and if they were, trying to figure out how we can adjust the cradle so it does not interfere with incubation, is our responsibility now. We can't just throw our arms in the air and cry 'Haven't we done enough?

Central Park Caterpillar

Photo by M. Winn

Found this tiny caterpillar [magnified in the photo shown above] last Wednesday, took it home in a little container and finally identified it with the help of my absolutely favorite Field Guide, David Wagner's Caterpillars of Eastern North America.

It is a Forest Tent Caterpillar, [Malacosoma disstria] something of a woodland pest though not as destructive as the closely related Eastern Tent Caterpillar. Nevertheless I did not release the caterpillar back in the park.

David Wagner writes: "Beautiful bluish caterpillar with white 'footprints' that lead towards head." The word "footprints" was the big clue for identification. That's exactly what those white splotches on its back look like.

Thursday, May 10, 2007

More migrants here than in Central Park today?

Black-throated Green Warbler

Common Yellowthroat [a warbler]

Blue-headed Vireo

House Finch

All photos above taken yesterday by DAVID SPEISER who writes:

The migration continues to baffle the best of us. Another relatively slow day but I am enjoying the few friends that let me share a brief moment of their time.

PS Today was another very slow day in the park, warbler-wise, though the winds were favorable to migration last night. Right now the park is usually chock full of magnolia warblers, redstarts, Cape May Warblers etc. These are few and far between. David is right -- the absence of warblers is baffling. Yet it seems there are a lot of birds already settling in on their nesting grounds..[at Doodletown Rd, for instance]. It may be that unusual weather conditions caused the usual large wave of songbirds to bypass Central Park on their northward journey.

Wednesday, May 09, 2007

PM & Lola note and first CPS baby picture

First baby picture from the Central Park South Hawks' nest --May 8, 2007
Photo courtesy of Http://

PM & Lola note:

A recent website posting to the contrary, many people are working on getting the eggs in the nest at 927 Fifth Avenue retrieved. And that website posting to the contrary, everyone is working on this issue in good faith.

I spoke to Ward Stone at DEC two days ago, Here's what he told me:

"I've talked to Chris Nadareski about grabbing those eggs, and he said he was going to do it in the next few days."

Chris Nadareski is the man at DEC who retrieved the eggs last year after Pale Male and Lola finally abandoned the eggs. That was too late to test the egg material for whether it was fertilized. It's good news indeed that Chris has signed on for retrieval while the hawks are still in residence. That will certainly be harder.

As Fiorello LaGuardia used to say when he was mayor of New York City long ago, what's needed is "Patience and Fortitude.

[I've had a huge amount of e-mail from people upset about that particular website posting. I can't answer it all. I hope the above news helps calm down everyone's anxiety.]

Tuesday, May 08, 2007

Migrants migrants migrant

All the birds below were in Central Park yesterday or the day before. But none of them were there this morning. Indeed, very few birds to be seen of any sort. A quiet day. Meanwhile, news had spread about the rare and exciting sighting of the Kentucky warbler yesterday, on the south side of the path in Strawberry Fields. So scores of birdwatchers were looking for it this morning. The beautiful warbler did not oblige with his presence.

Kentucky Warbler [!]- May 7, 2007 --at Strawberry Fields
Photo by Lloyd Spitalnik -

Spotted Sandpiper - May 7, 2007
Photo by David Speiser

Prairie Warbler - May 7, 2007
Photo by David Speiser

Indigo Bunting, May 6, 2007
Photo by David Speiser

PS Why so few birds today? Answer: The winds were unfavorable. A mass of songbirds heading north is probably clogged up somewhere to the south waiting for good southwest or southerly winds to give them that needed northward push. You can be sure that when the winds become favorable there will be A BIG DAY in Central Park.

Map of redtail locations around NYC


You [ in John Blakeman's letter, that is, MW] closed the main part of your Monday blog post with the sentence:

"There are a pile of red-tail eyasses sitting right now on NYC nests awaiting bands to answer this question."

Attached is a Google map I was maintaining of hawk sightings about the city which you might find of interest. It basically marks the spots in the pile as of a month or two ago.

The yellow and white markers are locations where active hawk nests were observed this year or last. (Ten of the 11 have been reported active this year, but I haven't heard anything about the Pelham Bay Golf Course yet.)

Green markers are reports of hawk activity. Bigger markers usually mean more reports and so one suspects a nest in the area. Some of the little green ones are close enough to nests that they may indicate some roaming around.

Purple markers were juvies were reported over the winter.


PS from Marie: I saved the map Robert B Schmunk sent me, and uploaded it to this site. It looks a bit small. I'm hoping that if you click on it it will enlarge and be more legible. In any event, thanks, Robert.

PPS: Just checked it from another window. YES! It enlarges beautifully. Now I can see how many, many redtail nests there are around the city. More than I thought.

Monday, May 07, 2007

Blakeman on redtail proliferation and a correction at the end

Female redtail feeding two young at Inwood Hill Park
Photo by Bruce Yolton
- May 5, 2007


The reports of multiple breeding red-tailed hawks in the various boroughs and regions of New York City are particularly gratifying. They substantiate my previous contention that red-tail habitats in the rural areas of The East are saturated with breeding adults. New adults have a hard time finding open habitats or territories, so they've drifted into the cities and begun to adapt their hunting and breeding behaviors to urban environments.

Everyone observing these hawks should understand that these new pairs and nests are essentially unprecedented, beyond any red-tail expert's prognostications. No one ever anticipated this urban incursion. A search of the red-tail literature is unlikely to find many historical accounts of these hawks breeding more than incidentally inside major cities in the past.

First, it was Pale Male in Central Park, and for a decade he and his mates were only a curious anomaly. Those of us who know the species in typical rural areas had to finally accept Pale Male's continuing occupation of Central Park. But honestly, few of us thought that there would ever be more than two or three other incidental urban nests and territories in a place like NYC, either on Manhattan proper, or out in any of the more open boroughs.

All of this is a very recent phenomenon, beyond what anyone would have expected. Until Pale Male began the affair, red-tails just didn't nest on buildings or in dense city centers. And if they did, they certainly wouldn't persist there. Surely, only a few other red-tails would continue the experiment.

But now, red-tail nests are all over NYC. Who knows how many are yet undiscovered. There is no longer any doubt that these big hawks are in the city to stay. Only two big biology questions yet need to be answered, and I post them for everyone's consideration.

(The earlier big, pivotal questions have been answered. What, in the city, are these vole-loving hawks eating, and how are they capturing their prey in the city? NYC hawkwatchers have provided the answers.)

The two remaining questions are these. How closely related are the NYC red-tails? Are they closely-related siblings or cousins, or are they multiple, unrelated individuals from distant rural populations?

The second big question is what will be the final, saturation density of the red-tailed hawk population? In the end, how many red-tails will be able to live

This last question could be answered by simple observational diligence. Someone needs to be putting nest dots each year on a map of NYC, showing annual population increases. In time, the number of dots (as they have out here in rural areas) will stabilize.

But the other question, the relatedness of the population, can be answered in only one way. A number of observers have noted pale-headed NYC red-tails, implying descent from Pale Male himself. Personally, I'm not very convinced by this. I have here in northern Ohio a big female red-tail that I've watched now for two years who has a remarkably pale head. This is coloring is infrequent, but not so much as to accurately impute descent from any particular pale-headed adult.

The only way to determine if any of the CP or greater NYC red-tails are related would be to begin a banding program of the eyasses on nests right now. Eyasses can be successfully banded almost right after hatching. By the end of the first week, banding is always successful as tarsus (leg) width approaches that of the adult. The band just won't slip off then.

And for those who would be concerned that humans reaching into a nest and picking up eyasses would so disrupt things that the adults wouldn't come back or feed the young, let me assure that this is an artificial contrivance intended, perhaps, to keep little boys from messing with schoolyard robin nests. Thousands upon thousands of birds have been banded as chicks in the nest, and parents always come right back and properly attend to their duties. Neither adults nor eyasses will be disrupted by banding. It's not an issue of any concern. I've assisted in the banding of a number of red-tail eyasses on nests, and in every case all was well in the end.

Because the CP and NYC red-tail populations are new and unique, special permission should be gained from US Fish and Wildlife Service authorities to band not only with conventional bands, but also with colored bands to allow easy ID of locally-produced eyasses.

Until the NYC red-tail eyasses are banded, no one should be suggesting that any new birds are descended or related in any way to any other known red-tails. Most of that is mere hope or romance. The biology right now doesn't support such suppositions.

And as I mentioned sometime in the past, genetically, for survival, it would be far better that all of the new NYC parents were unrelated. If the majority of the new NYC red-tails are descended from Pale Male in Central Park, inbreeding will be a problem in consequent populations.

One last point. The question of whether or not maturing young adult red-tails actually return to their natal territories, or even to their general natal regions, is really unanswered. Today, with all the new NYC eyasses on nests, there is a unique opportunity to answer this question.

Once again, a proper study of the NYC red-tails could provide missing information for the species. Raptor biologists don't really know for sure if youngsters return as adults to their natal territories. There are a pile of red-tail eyasses sitting right now on NYC nests awaiting bands to answer this question.
--John Blakeman

PS A correction
Bruce Yolton writes in about yesterday's posting:

In your report on the St. John the Divine nest, you wrote
"Though these hawks hunt in Morningside Park, not Central Park, it is one of the neighboring redtail nests featured here this year, in the sad absence of nestlings of our own."

Although the picture shows a rodent caught on the grounds of the Cathedral, both St. John's adults hawk do hunt in Central Park. Both hawks are seen in the area around the Great Hill frequently and do so both during the nesting period and during the "off-season".

Sunday, May 06, 2007

Cathedral Papa brings supper

The Cathedral of St. John the Divine's Papa redtail delivering a mouse to yet-unseen babies. Note the resemblance to Pale Male.

The bowl of the nest is deep and the nestlings are not yet big enough to be seen by their eager fans. Soon! But photos like the one above, taken on Thursday, May 3, by BRUCE YOLTON, give proof [through the day and night] that the babies are there.

This picturesque nest is tucked behind the arm of a monumental statue of St. Andrew of the Diagonal Cross,. The statue may be found among a row of others on the Cathedral's northern facade on 113th Street, between Amsterdam Avenue and Morningside Ave.

Though these hawks hunt in Morningside Park, not Central Park, it is one of the neighboring redtail nests featured here this year, in the sad absence of nestlings of our own. At 927 Fifth Ave, Pale Male and Lola continue to sit on their nest and will probably do so for another few weeks. Meanwhile, plans to retrieve the eggs for microscopic analysis continue to progress. I hope it will happen soon.

If you're not in danger of webcam addiction, check out the Queens redtails at

More news soon about the Inwood Hill, Highbridge, and Fordham redtails. Flash! It looks like there are nestlings at a new location -- Green-Wood Cemetery. You can check those out on Rob Jett's excellent website

PS The explosion of urban redtails around here is nothing short of amazing. I'm sure there are other local nests I haven't included in this round-up.

A formidable birdwatcher turns fourteen

Liliana just turned fourteen [months]. She's walking unassisted, perhaps to get a better look at the beautiful warbler below

Ovenbird -- May 5, 2007
Photos by David Speiser, Liliana's birding assistant.