3/16, Almost Nesting Time on Morningside

Early this evening, Isolde of the Cathedral of St. John Divine red-tailed hawks was hanging about her nest, watching the skies and perhaps enjoying the clear air (after a rainy morning). The amount of time she spent just sitting there suggests that egg-laying time is approaching, but that she was sitting rather than laying down in the nest indicates she hasn't done so yet.

A couple minutes after 6:00 she perked up and stepped out on the north side of the nest. She flew across the street, perched on the roof of the hospital for a minute and then took off northward again. I found her perched with her mate, Norman, on the roof of 54 Morningside Drive, at the corner of 116th St.

Morningside Drive Red-Tails

Apparently a food delivery had been made, as Norman took off a few seconds later.

Morningside Drive Red-Tails

And flew down to the hospital where he perched for a moment.

Hospital Red-Tail

Meanwhile, Isolde had started chowing down.

Dinner at 50 MSD

Can't quite tell what it is yet.

Dinner at 50 MSD

She stopped eating after just a few minutes. Gave me and another hawkwatcher the hairy eyeball.

I'm Watching You

Maybe had another peck or two then stood up and looked around. Then back into the air, flying south along MSD.

Red-Tail over Morningside

Ah, dinner was a rat, and apparently she just wasn't hungry enough to consume it all in one sitting.

Red-Tail over Morningside

And back to sit around the nest some more.

Back in the Nest

In case you're wondering when Isolde will lay her eggs and when a hatch would occur, well, all we can do is guess based on what happened in prior years. Keep in mind that incubation takes 28 to 32 days.

In 2010, we know she had laid egg(s) and was incubating by March 17, and that a hatch occurred between April 13 and 18. However, last year was the earliest we'd seen this, by a week or more.

In 2009, Isolde apparently did not use the cathedral nest. Or possibly there was a very early nest failure and she and Norman did not try for a second clutch. This was right at the end of the cathedral's repair project and the hawks might still have been stressed and behaving oddly.

In 2008, egg-laying did not occur until after the first of April. That was also the year when she lost her prior mate, Tristan, and then the cathedral erected scaffolding all around the nest area, so things were pretty disrupted.

In 2007, egg-laying occurred about March 23-25 and hatch before April 27. No one was observing in 2006, but other evidence sugests it was roughly the same as 2007.

So... best guess is that egg-laying will occur next week.

Posted 3/16/2011 08:11:00 PM by Robert

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