Sunday, March 27, 2011

As the nest turns....

One of the great delights of the Franklin Institute's camera feed is catching some of the daily dramas that occur in the nest.  

Last week, as we waited for the third egg to appear, the tiercel kept bringing more trash to the nest.  In addition to his favorite plastic bags and newspaper sheets, a spatula appeared!

Then more newspaper showed up under the eggs...

 ... followed by more plastic and another sheet of paper.

 In addition to nest lining materials, the tiercel also brought great dedication to sitting on the eggs.

On one occasion, he literally pushed the formel up off the eggs....

... and nestled in under her, leaving her no choice but to leave the nest with the tiercel sitting happily on the eggs. As the formel came closer to laying her third egg, she had to be forcible in her presence until she succeeded in moving the tiercel off the eggs...

 ... finally gaining her spot back ready to lay her third egg.

I asked John Blakeman what might be causing the tiercel's insistent behavior towards his mate, and he responded:

"Not sure I can explain this, except that the formel is still not incubating. She's merely covering and protecting the two eggs. They are being held at sub-incubation temperatures, awaiting the laying of the final egg. Then, the formel will dominate and will not be nudged off her now-warm eggs unless she so subtlety signals that she needs to take a break.

But none of that explains the tiercel's pushy desire to cover the eggs himself. My best explanation of this would be that the tiercel was just trying to help, to give his mate a break, something he will be doing much more helpfully, and less insistently, after formal incubation begins (by the formel, the female).
It seems that the pair can send and receive the slightest behavior signals, by nuanced and slight gestures that none of us can detect or read. Right now, before incubation begins, the pair are practicing and trading signals. This may have been a part of what you saw.
But soon, the final egg will have been laid, and full incubation will begin, with no looking back or extensive neglect of the eggs.
In that regard, however, as viewers so nervously noted last year, there will be times when neither the tiercel nor the formel will be sitting on the exposed eggs. This will cause anxiety for everyone except the hawks themselves. Somehow, they always get one of the pair back on the eggs and warm them up again before anything untoward happens.
Real incubation is about to begin. Let the show begin."

--John Blakeman


  1. Love the spatula in the nest. Must be the Hawk equivalent to us finding a real "treasure" in some one else's trash. I mean, how many Red tail nests can boast a REAL broken
    spatula? So much fun and so interesting.
    Thanks as always.

  2. Wonderful as usual, a great resource for those of us who cannot keep the hawkwatch vigil!

  3. Ahh now we know this pair work for Mayor Nutter on his council for Creative Recycling This is quite an interesting selection especially the spatula

  4. This is really interesting as my red tails are doing the same thing. The male is on the nest at both locations and the female is flying around calling him to mate occasionally. Thanks for the information.

    Ann Brokelman