Locked talons, more ledging: Fledge Day getting close

As always, events at the Franklin Institute hawk nest happen almost too swiftly to keep track.

Last week, Scott Kemper captured this amazing moment when Mom and T2 locked talons while soaring over a nearby apartment building.  This is HUGE!

            Scott Kemper

This behavior is usually only seen in late winter or early spring when the haggards begin their courtship flights, soaring in circles high above the city. Locking talons while soaring is profoundly sexual, and indicates very significant commitment between two haggards.

I asked John Blakeman for his assessment of this event and how unusual it is to see summer haggards with eyasses on the nest engaging in this behavior.  He commented:"This is uncommon, but not unknown. Amorous behaviors continue often through the entire spring, including copulation in May or even June from time to time. This pair [Mom and T2] is locked, physically and socially." 

JB commented further about the astonishing events at the Franklin nest when he was interviewed recently by Donegal Browne for her excellent Palemaleirregulars blog: 

"The T2 saga at the Franklin Institute is remarkable. I know of no other instances of this -  where a floating haggard came in and essentially took all the functional duties of a very recently killed resident haggard, right at the start of the brooding of hatched eyasses. The behavioral adaptations required for this are remarkable. We falconers see and know the full hunting and killing powers and mind-sets of Red-tails. It's remarkable in and of itself that tiercels can convert themselves from hunter/killers to food providers and feeders of their own eyasses. But in this case, the new tiercel came in, and almost instantly took up those duties. The hormonal and psychological mechanisms of this are astonishing. And finally, T2 carefully feeds his step-eyasses. Who'da thunk?"  

So all this bodes well for Mom and T2 to remain together and, hopefully, continue to nest at the Franklin Institute.

Meanwhile, back at the nest the eyasses continue to eat voraciously from the food provided by the haggards, and from the food drops on the ledge.  T2 is not yet the hunter Dad was, and brings mostly voles and small birds with the occasional pigeon and squirrel.

 

Here's a chart that shows the relative size of these food prey items from largest to smallest. 

We do not see #'s 1, 2 or 5 in this region.  Pigeon - a Philadelphia special - is not listed, but T2 has brought a couple in for breakfast.

      George Lloyd

The eyasses are also becoming increasingly strong in their wing flapping and jumping.  Last week saw all three out on the ledge together for the first time.

            George Lloyd


On May 31, the bouncing was getting higher, but still facing the window.

                              George Lloyd

    Scott Kemper

                     George Lloyd

By yesterday, at least one eyass was bouncing facing sideways, then forward, a sign that its fledging is imminent.

         Joe Debold

         Joe Debold

 
The other indicator for fledge-readiness is how far the feathers are out of their casings.  Casings are the sheaths from which the feathers grow.  Donna Caesar posted this helpful image on the Franklin Hawkaholic Facebook page (these are not hawk feathers).

Here is what the eyasses' feathers looked like last week.  You can clearly still see the casings at the base of the wing feathers.

           Kay Meng

           Christian Hunold

 Yesterday, the sheaths were much less visible.

         Joe Debold

 John Blakeman shared important information about this feather development:

"As the feathers grow out, they actually have blood vessels within, nourishing the growth of these miraculous body features. So, for a while, heavy blood remains coursing through the big tail and wing feathers. Until this ends, when the bird is “hard penned,” the wings are a bit heavier. Right now, all three birds should be close to being hard penned, allowing for much better flight.

The feathers have not completely emerged from the feather sheaths. That’s what the eyasses have been attending to for much of each day in the last weeks. Everyone has noticed how much time the birds spend “preening,” tucking their heads down into their feathers. They are using their bills to strip off the drying feather sheaths, allowing the growing feathers beneath to emerge. For the large flight feathers, the feather sheaths still remain at the base and shank of the larger feathers."

Here's what mature wings look like:

Mom...

          Joe Debold

... and T2

                  Kay Meng

There's very little baby fluff left on the eyasses now.

              Kay Meng

#3 in the middle shows that it's two days younger with some wisps of fluff still on its head.

              Joe Debold

Another developmental milestone is the color change in their eyes from black to gold.

         Christian Hunold

          Joe Debold

With all their jump flapping and wingercizing, the eyasses are expending lots more energy, as well as growing bigger every day, so the food drops continue to ensure they are getting sufficient food.  

Carolyn Sutton is the most frequent food dropper, and she is clearly a familiar face to the eyasses, as she carefully pulls the window pane back to slip out the food item.

           Scott Kemper 

The trick is to get it out on the ledge, and one's hand back inside before Mom catches sight with her hawk eyes.  We always wait until the haggards are off the nest, and perched elsewhere, but one of them is always in sight in of the nest - usually Mom - and the moment she sees the window open, no matter how slightly, she comes in like a freight train. An incoming formel is a fearsome sight!

         Kay Meng

         Kay Meng

She grabs it with a talon...

         Kay Meng

... and heads up into the nest with it.

         Kay Meng


This is a view from the ground.

         Scott Kemper


It is a matter of mere minutes for Mom ...

         Kay Meng


... to get the rat opened up, skinned, and fed to the eyasses.

         Kay Meng


Mice are also put out on the ledge, and T2 takes his turn at delivering them.

         Kay Meng

          Kay Meng

Sometimes the mice are taken away and stashed for future feedings.

         Scott Kemper

         Scott Kemper


At the end of the nest feast, the remains are always removed and provide the haggard with a quiet snack, usually on top of a nearby monument or ledge.

                      George Lloyd
       

                George Lloyd

I am so incredibly appreciative of the talented photographers who have captured these gorgeous images, and who allow me to share them in this blog.  


Here are some more stunning pictures of the haggards - first of Mom.

         Kay Meng

         Kay Meng

          Scott Kemper 

      Scott Kemper 


... and T2

          Kay Meng

         Scott   Kemper

                    Kay Meng


We've reached the last few bittersweet days of the eyasses on the nest.  Sad as it is to see them go, it's what they need to do.  How astonishing it is to think back over the amazing events of the last few weeks when their survival was at stake.

Thanks to the outreach from the Franklin Institute to do food drops, and the arrival and acceptance of T2, it looks as if we will soon see the eyasses launched out into the world.  And then the hawkstalkers on the ground here in Philadelphia will get in gear to bring you frequent reports and pictures of the hawk family.