John Blakeman on the Flegling Upside-Down-Head Move and the 90 foot Elm Tree That Obliterated My Back Yard

 Photo Donegal Browne
Fledglings of Tristan and Isolde at the Cathedral Nest of St. John the Divine, 2006.  One of which is doing the upside down head move.

And here is Red-tailed Hawk expert John Blakeman with a theory as to why they do it..

Donegal,

The upside down posturing of Red-tail eyasses and fledglings is well known, especially among falconers. It’s just plainly cute and endearing — but its purpose and functions are unknown. It seldom happens in second-year Red-tails, and virtually never in haggards (full adults).

My explanation is that it helps fine-tune developing reflexes between the eyes, neck muscles, and the visual portions of the tiny Red-tail brain. I believe that the bird is learning to process visual information that occurs in varying orientations — a factor of great importance when in flight at various angles, compared, to the un-varying horizon. Learning this statically when perched obviates any in-flight crashes caused by visual misperceptions.

–John Blakeman

John,

Thank you for your explanation.  It makes perfect sense.  My intuition was it had something to do with processing vision but I wasn't sure what.   Not only is it cute and endearing there is also a bit of the weird about it for the first time viewer as the head is where it "should be" and then suddenly it isn't. The first time one sees it, it has kind of an Alice in Wonderland feel to it,  rather like seeing the skunks that stand on their hands for the  first time.  

I've also seen several fledglings obscuring the vision of one eye with a pillar or branch then looking with two eyes, back and forth.  I suspect it is similar to checking out binoc vision similar to the experimentation of young humans who cover one eye with a hand, take it off, look with two eyes and then look with a hand over the other eye.

Now on to other weird matters... 

The day before yesterday, I woke up at about 4:45AM.  I wasn't sure why as this isn't ordinarily when I wake up.  I  then began to hear voices, rather excited ones, outside.  Also a rather un-ordinary thing to happen.  I pulled on some clothes and went out.

This is what I saw.

  5:01am My side neighbor's  90 foot Chinese Elm had uprooted itself...

 in a freak localized storm, which I had peacefully slept through, and taken out three quarters of my hundred year old maple... 

 and a quarter of my two hundred year old oak.

Though the trees did better...

 than the fence I share with the back neighbor.
My back neighbor got half of the side neighbors elm...

 and I got the other half.  But at least it missed my house.  The back neighbor had his house roof and his garden shed clipped when the tree came down.

And this sort of thing happened all over town and not really anywhere else  

The town was declared to be in a state of emergency. 


Bizarre.

And in daylight, it didn't look much better.  This is the tree neighbors yard.  Note the uprooted elm on the right and it's mid-section and top making it's way left, crushing my fence and entering my yard.  Sigh.

But it did bring out a few Good Samaritans with chain saws...

 who burn wood for heat in the winter.  They saw it up and help you clean it up and they get a good bit of wood you don't need as you have plenty already.  In my mind an excellent solution to the problem in which no grand amounts of money have to go to a tree service.

AND...I got to take a zillion trips on the four wheeler with the little red cart full of tree limbs to the towns wood chipping area.  You have never seen so many vehicles of of so many kinds carrying tree limbs in your life-everything from Farmall tractors with manure wagons to T bird convertibles. 

Plus I did find some very cool gooey brown fungus.

Oh no it is not done yet...but I'll keep you posted.

In the meantime...Happy Hawking!

And remember you never ever know what is going to happen next...so do try and enjoy it!
Donegal Browne

 Photo courtesy of www.palemale.com/
Two of Octavia and Pale Male's fledglings play the upside down head game.

Photo by Donegal Browne

As did the fledglings of Tristan and Isolde back in 2006.  

 What is  this upsidedown head thing? It is a repeater behavior of young Red-tailed Hawk fledglings.  I think it has something to do with experimentation with the marvelous and new to fledglings  vision of Red-tailed Hawks but I am hypothesizing.

Any other thoughts as to why?  

 

Well it might just be great fun if you are a young Red-tail right?

GOOD GRIEF!!!!  Blogger isn't responding properly at all, in fact it is being totally bizarre....more to come when he straightens out.

DB

As it happens-- Stella Hamilton Finds Pale Male's Fledglings Near the Great Arch in Central Park

 Photo by Stella Hamilton

 Stella has done it again.  She's tracked down Pale Male and Octavia's fledglings over near the Great Arch.

5:53PM  Fledgling attempts to catch a squirrel in a tree.

One of the first lessons Central Park Fledglings learn is that they can't catch a squirrel in a tree.  I've never even seen an experienced Red-tail working solo nab a squirrel in a tree.  The squirrel just scuttles to the other side of the trunk or if on a branch he zips under the branch when the hawk attempts to grab him.  Youngsters have to learn that a squirrel has to be on the ground to get caught.  

Experienced hawks use stealth.  They sit and wait for a squirrel to go to ground and that's when they swoop in.

 Photo by Stella Hamilton
6:08PM Two of the Fledglings look for scraps.

While waiting for dad to "bring the bacon" most often these days a squirrel or a rat, the youngsters look for scraps and or mimic the killing of mock prey. The "play" of all young predators develops their hunting skills.  Young Red-tails leap onto sticks or good sized rocks, grasp them in their talons, then jump up and down with them which is really quite hilarious, and then "kill" the stick or rock. 

6:16PM  Up in a tree, the third eyass looks to the sky for a delivery.  Dad where are you?

Currently Pale Male will be making regular deliveries of prey to the youngsters.  As time goes on the intervals between meals will lengthen as the hawk parents help their progeny to develop hunting skills by bringing on an edge of hunger between food drops.

7:29PM Fledgling finds water in a depression of a branch and drinks it.

Obviously on the nest, eyasses receive all their water needs from the prey they eat. 

In fact when I first started watching Red-tails there was no information in the scientific literature as to whether or not Red-tailed Hawks drank water or even  bathed.

Central Park Hawkwatchers with their multiple and far more intimate observations of human habituated Red-tails as opposed to scientists who tended toward population counting and the like,   saw both these activities but as they weren't of name so were not believed in some circles.  Then Ann Shanahan, long time wildlife watcher and photographer in Central Park got photographs of both activities.  

Score a big one for the citizen scientist!

More as it happens.

Happy Hawking!
Donegal Browne