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Trust Me They're In There

Both Robert and James have had reports on their blogs about signs of the St. John the Divine nest hatching, earlier this week.  Once I hear a report like this of a nest hatching, I have to travel to see what's up.

The nest is behind the shoulder's of St. Andrew and is very deep.  Every year it seems to get deeper, too.  This makes it hard to see the young eyasses.  We can see the feeding, and we can see the slices (poops), but we can't see the young birds.  On Saturday, I positively knew they had hatched but couldn't see them.  Once they get bigger, we'll be able to see them and count how many there are.  But not now...

The bare spot on the mother's chest is her brood patch.  You almost never see it, but the wind was "just right".


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Still Waiting

Tonight was fairly quiet.  Once the kids hatch, we'll see lots of prey brought to the nest and there will be alot more action.  I can't wait.

(It should be noted that it is not uncommon for newly built nests to fail.  It's a small chance but it does exist.)


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Washington Square Prognosis

I've gotten a few letters about how excited individuals were about the Washington Square Hawks.  I think it's important to say that until we see how these hawks do in Washington Square, we should have limited expectations about how things will turn out. 

In general, 70% of all birds die in their first year of life.  It's a hard fact of nature.  Birds have a high mortality rate.  Most birders learn this their first or second year of birding.  For me, it came when I was watching a mallard and her ducklings.  I was photographing the ducklings and an elderly birder came up to me and said "Don't get too attached to them, there will be one less ever few days."  She was right.  Mallards start with a large number of ducklings, maybe a dozen and as much as they try, they slowly get taken by turtles or other birds.

Since that day, I start with low expectations when watching a nest.  It makes birding easier.

Whenever we have a new nest I do my own estimates about the conditions of the nest location and the parents.   I ask:

  • Is the nest in a safe place?
  • Is their enough food and is it safe?
  • What will fledgling be like?
  • What will the area that the fledglings grow up in be like?
  • Are the parents young and inexperienced?

At Washington Square, two issues worry me.

  • The food supply includes rodents that have been exposed to second generation anticoagulants.  Both the parks department and the health department have been using Contrac, which has an active ingredient of Bromadiolone, in and around the park. 
    I don't know if the other major cause of death for young hawks, frounce is present in the pigeon population in Greenwich Village, so it's unclear if this will be an issue.
  • The park is the smallest area other than the Houston Street nest (which didn't end well) we've seen for the fledglings to mature.  The density of the park patrons and number of unleashed dogs is a serious concern.  There most definitely will be some conflicts.

So, my guess is we have a below average environment for these hawks.   If one or two make it until the end of the summer, we should be happy.

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Although taken on 4/23/11, this form appears to be dated 4/30/11.  I don't know if the poisons have already been places, or this is a notice they will be placed on 4/30/11.


Happy Easter From Riverside

There were at least two active eyasses on the nest today. (At this stage, they're too small to know if it's two or three.)  If you go watch them, be aware that you can only see them from the ridge by the highway at this stage.  All I can say is they're more fun to watch than Easter Bunnies!


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Good Friday In Washington Square

Bobby, the male Washington Square Red-tailed Hawk was hard to find for most of the evening.  He appeared briefly on the nest around 5:00 but then wasn't seen until he returned to his favorite perch on the cross of Judson Memorial Church around sunset. He then made a brief stop on a Bobst Library ledge (one east of the nest), and then went off to roost in the NW corner of the park.

The New York Times City Room Blog posted a link to my site. I thought it would be helpful for the webcam viewers to have a chart of locations Bobby has been seen off the nest.  There's a lot more than the 3 foot by 3 foot view the webcam shows!

Map

1) Nest location on Bobst Library
2) Cross on Judson Memorial Church
3) Favorite Flag Pole
4) Failed 2010 One Fifth Avenue Nest
5) Various other perches


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Note the two cameras, the higher one is the repositioned infrared night camera.

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Riverside Eyasses

I could see the mother settling down, as I approached the Riverside nest, so I think I had just missed a feeding.  So, I had to be patient and wait for a glimpse of an eyass (hawk nestling).  Just before nightfall, I saw two brief glimpses of an eyass, possibly two.  They're easiest to see on the video.

The father was near the nest for about half an hour. 


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Fifth Avenue Brooding

Pale Male was in some trees north of the Model Boat Pond when I arrived from Riverside Park late this afternoon.  He soon flew to a "Linda" building railing and took advantage of the late afternoon sun.  The dark female was on the nest and looked very settled in.  Much more so, that the fidgety days of last week.


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Positive Hatching Signs At Riverside

Thirty M.P.H. winds made it difficult to observe and photograph the nest Sunday afternoon, but there were positive signs that one or more eggs may have hatched.  The mother ate on the nest and appeared to be sharing food.  It wasn't conclusive and she may have just been "eating for one", but it did look like she might be feeding.  We'll know for sure in a few days.

The father joined the mother on the nest but there wasn't an exchange.  Another sign one or more eggs may have hatched.


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Brooding At Fifth Avenue?

It looks like egg laying has started on Fifth Avenue, but the mother is acting a little inexperienced.  She stood and preened after sunset for at least half an hour tonight.  She may not have laid all of her eggs yet so "no worries", but the behavior seemed out of place.  I guess we have a young mother. 

This is going to be a fun season.  I suspect everything will be slightly different now that we have a new female.


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Quiet Evening Except For The Musicians

The male at Washington Square was hard to find this afternoon.  He only made a few appearances and flew towards Broadway at dusk.  The tall buildings on the square make it difficult to figure out where he goes, and how large the territory is.  Could it be as far east as Tompkins Square?  How far into the Village?  Does it go south to Houston?


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Another Overnight On 5th Avenue

The Dark Female (Ginger/Lima) spend another night on the nest this evening.  Around 7:40 p.m. she circled the area of the hawk bench and then landed on the nest. 

My original hypothesis about this year's nesting seems to be holding true.  I thought that the Dark Female, who was hanging around with a young hawk who she stole food from, didn't yet have the hormones to bond properly with Pale Male in January. 

This allowed the Pale Female (Pale Beauty) to come in and try to bond with Pale Male later in the season.  But I think she was too young to lay eggs yet, so things didn't work out.  She never seemed interested in the nest.  I believe this allowed the Dark Female, who was now more motivated to mate since the days were much longer, to move in and displace her.

Even though it was late in the season, I wasn't concerned.  Triggers other than longer days must play a part in getting a female to ovulate.  This must include copulation, nest building, constant displays of food by the male, etc.  With help from other hawk watchers, we estimated that it would take three to four weeks for the Dark Female to ovulate from the date of her return.  It's been sixteen days since the Dark Female returned, and now our timing estimates look like they might be correct.  I certainly hope so!


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St. John The Divine

I finally got a chance to visit St. John the Divine on Sunday.  The St. John the Divine Red-tailed Hawk pair go into stealth mode when they nest.  The nest allows either parent to completely hide on the nest and the the parent who is off the nest usually stays hidden before the eggs hatch.

I spent an hour and half at the nest and only got to see the parents for about a half minute during an exchange.


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Washington Square On Saturday

I arrived late in the afternoon, and realize I'm going to have to arrive earlier in the day to see some hunting.  The male spent most of his time perched on either a flag pole or on the cross. 

There was a brief bit of activity while he escorted a hawk from the western side of the park to the east which included a few stops along the way. 

While the nest is in a great location, the park really seems too small and too well used to raise fledglings in.  It will be interesting to see what happens this summer.

(This is my 1,000 blog post.  I never imagined making this many posts, when I started urbanhaws.com years ago.)


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Eating On The Beresford Apartments

As the Dark Female begins to settle in, Pale Male has been introducing her to his full territory which includes the Beresford Apartments at 81st and Central Park West.  Pale Male eat and gave leftover to his new mate on the south tower of the building on Saturday.


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Washington Square

After years of juvenile hawks, and last year's pair of unsuccessful nesters, this year Washington Square finally has an active nest with three eggs.  The nest is on a window ledge of Dr. John Sexton's office, President of the university, at N.Y.U.'s Bobst Library.  This location continues the pattern of hawks in Manhattan finding spectacular places to build nests.

The library is on the south east corner of Washington Square on West 4th Street.  The nest is on the side of the building that faces the park, on the top floor, the second window from the west.

The New York Times had a nice feature on the nest yesterday, and has set up a webcam to view the nest.  The streaming feed is on Livestream.com, which also provides applications for the iPhone and iPad.  If you use these applications, search for NYT Hawk Cam.

The mobile feed is exciting since it will allow hawk watchers to go to the park, and get a webcam view of the nest on their mobile devices, while simultaneously watching the other parent off the nest.

The ledge the nest sits on is fairly deep, so the brooding female is usually hidden from the street.  But if all goes well and the eggs hatch, the eyasses will be easy to see after three or four weeks. 

New York Times/NYU, Livestream Feed above.

My video and photographs from the park perspective on Thursday evening are below.


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A Rainbow

As I came into the park, there was a wonderful rainbow over the east side.  Later, I followed the the dark female fron the "Woody" building to the Beresford Apartments.  In Lola's favorite spot, it was like seeing a ghost. 


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Patience at Riverside

Watching a hawk sitting on a nest takes patience!  Tonight, at the Riverside Park nest near the Boat Basin, it took lots of patience.  The female sat on the nest and almost nothing happened.  All of this is a good sign, but it makes for a dull evening.


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Saturday On Fifth Avenue

On Friday, I posted a request for information about what triggers ovulation in a female hawk and what the logical time frame would be for the Dark Female to lay eggs.

Katherine Herzog and Pamela Langford offered some excellent insights.

Katherine reminded me that Pale Male and Lola usually started courting behavior around mid-February and nested in early-March, so they had about a four week window.

Pamela asked a biologist for my question.  The answer was that scientists don't know all of the variables.  Certainly, time of year/daylight and food supply play a large part, but scientists also know other factors such as behavior play a part.  (Even less is known about what triggers a second clutch, when things go wrong!)

So, given all of what I know so far, I only think I can say that we shouldn't be concerned if this new female takes up to four weeks to lay eggs or somewhere around April 22nd.  I could however be much shorter.  Bets anyone?

Saturday was typical of what has become the normal pattern at the nest.  Copulation, a shared late afternoon meal, chasing an intruder Red-tailed Hawk (whose identity is a mystery), and lots of nest visits primarily at this point by Pale Male.


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