Tuesday, March 27, 2007

Isolde amd Tristan: Caught Switching. It looks like Eggs!

Robert Schmunk of http://bloomingdalevilliage.blogspot.com and I had been discussing whether or not the Cathedral nest was deep enough and dim enough so that there might well be times in which there was actually a hawk on the nest but one just couldn't see it.

The answer to the question...YES.

Here are Bruce Yolton of
http://urbanhawks.blogs.com/ and Rob's sightings that clinched the answer.

Bruce and I were at the Cathedral today at 5:45 p.m. A hawk landed on Gabriel and a moment later flew down to the nest. It perched on St. Andrew's hand for a bit. I then made to move toward another location to see if I could get a better picture, and while I was at it there was apparently a switch-off at the nest, as Bruce says that the hawk that dived out a moment later was not the one we saw on the hand. The hawk that dived out went up to Gabriel after circling over St. Luke's a few times. Looking at pix afterwards, it was clear that the hawk first seen on Gabriel was Isolde, but that the one afterwards was Tristan.I had seen Isolde on Gabriel's horn at 5:00 before she flew off to the Great Hill, so it looks like Tristan was on egg duty from 5:00 to 5:45. One thing the episode also demonstrated is that the nest is too deep to see a hawk which is on the eggs. Before and after the switch, no hawk was visible in the nest.


Now if we could just figure out when the last time anyone saw both Isolde and Tristan out and about at the same time, we might have a ballpark figure of when they started to brood and therefore a vague idea as to when the eyasses might be hatching. D.B.

1 comment:

rbs said...

Per my blog posts, they were seen together outside the nest on Thursday the 15th.

Isolde was sitting in the nest on Sunday the 18th, but she was sitting high enough that her head could be seen at least once. But she then disappeared without my actually seeing her leave, which may or may not mean a lot.

Monday the 19th was the day that she was sitting in the nest 5 minutes after sundown.

Tuesday the 20th she was standing in the nest in an odd posture, which has made me wonder if she was laying an egg.

Based on all that, I think they're running a schedule a week or so behind PM and Lola, and about the same as the Fordham hawks.

So I'm figuring hatching around April 26th.