Monday, May 9, 2011

The Amazing Tiercel - Superdad

This is the third year we have watched the Franklin Red-tail hawks refurbish their nest, lay and incubate the eggs,  and hatch three healthy eyasses.  It is quite noticeable this year that the tiercel (dad) has taken on a more active role at each stage.

He was seriously involved with incubating this year. When the formel (mom) was sitting on the eggs, there were times when the tiercel would almost harass her to get her off, pushing and poking at her so he could get on them.  When she returned to the nest, the formel often really had to shove at him to get him off the eggs. 
Once the eyasses hatch, it is his job to hunt and bring back all the food.  For the past two years, the tiercel has flown in with his prey, dropped it on the nest, rested a few moments to catch his breath and then headed out.  

This year, he is staying longer on the nest, often tearing off morsels...

 ... to feed the formel as well as the eyasses.  

He has also brought prodigious amounts of food to the nest with carcasses literally stacked up around the eyasses....

 ... and bunny lovers everywhere are horrified at the carnage of the local rabbit population by the tiercel.

I asked John Blakeman whether the tiercel, as an experienced third time dad, was really getting on board with the joys of parenthood. 

John replied, "As the tiercel matures and experiences increased interaction at the nest with the eyasses each year, he takes on more of the usual duties of the formel, such as actually feeding the eyasses and trying to incubate.
His compulsive nudging of the formel, trying to get her off the eggs so he can incubate, is a part of this. In Red-shouldered Hawks (a related Buteo species), tiercels have been observed sitting right on top of incubating formels. The compulsion to incubate gets stronger with experience.
But now, hunting and feeding the eyasses are the focus of the tiercel. Right now, while the formel must still spend most of her time at the nest, the tiercel is responsible for feeding five mouths, his, the formel, and the three eyasses. He's got to be hunting every daylight hour. He's got to be a perfected killing machine, spotting, killing, and retrieving every prey animal he can find within a reasonable distance from the nest.
The camera allows us to watch the eyassses and the attending formel. All well and good. But the real star is the smaller (compared to the formel) tiercel, who's out providing for his large, food-consuming family. 
If he fails in his task, the eyasses die.
But this tiercel is a great success, a great provider. This will be another great Red-tail year at The Franklin Institute.
--John Blakeman

Last week, Kay Meng and I were fortunate to be able to visit the Board Room of the Franklin Institute and see Superdad in action, feeding his eyasses from a freshly killed starling

In between feeding them, he also ate ravenously himself, and the eyasses respectfully watched him gulping down the food he needs to fuel his extraordinary workload.

 When the formel returned, he immediately shared his starling with her.

 Then, it was time to go hunt again, and he was gone, leaving her to finish feeding the eyasses.

 As they reached their limit for food, each one started to tilt over, completely sated.

They could barely keep their heads up to watch mom take off with a half-eaten carcass...

... and then the food coma hit.

Over and out.......


  1. Love this blog! The info from John Blakeman is priceless. Thanks for asking him the questions we wonder about. And Of course the photography. Oh - and you also have a way with words. I have looked forward to reading this since you've been doing it. Thanks so much, Della!

  2. As always, a wonderful informative report.

  3. Thanks so much - I'm so glad people enjoy the blog. It's a wonderfully collaborative effort, and I have the fun of putting together John Blakeman's knowledge, Kay's pictures, and the Franklin Institute's camera feed. Great stuff!

  4. Last Friday, I saw one of the adults standing up in the nest as I drove by. Like seeing a celebrity.
    Thanks so much to all of you for your excellent reportage,
    words and pictures.

  5. Great blog Della as always! I have a desktop full of screen caps of each day that I think I can delete now, thanks to your intrepid reporting, Kay's pix, and John Blakeman's wonderful information! I was down on the Parkway yesterday along with 40,000 others walking in the Race for the Cure.....pointed out the nest and the formel sitting on it to my family ...amazing how 39,999 others walked right by not even knowing they were there! Ah well, their loss.....Great you and JB continuing the saga of our "family" for the 3rd year!


  6. Wonderful as always. Its a pleasure being able relive the day to day interaction between the hawks through the blog and photos. John Blakeman's contribution is invaluable.
    Thanks so very much!