Thursday, May 15, 2014

John Blakeman on the Real Scoop Concerning Imprinting in Red-tails, and a Mystery Hummingbird in Wisconsin?

As I mentioned previously, I'd gone to a fund raising event at an all volunteer staffed bird observatory.

As I walked amongst the exhibits and vendors,  I stopped in at the live raptor display area which as usual for this sort of event, has raptors who for whatever reason, a physical problem or because of imprinting issues, are not able to survive in the wild on their own so they are brought by someone who has permits to keep these birds to help educate the public about them.

While I was standing there, a person behind the table told another patron, if I heard it all correctly, that a particular bird had been imprinted on humans who had raised it after finding it under a tree.  The educator went on to say that raptors will imprint on anything they see first,  including an object like a toaster.

WHAT?  Hawks imprint like geese do?  They're precocial?  How did I miss that all this time?  But they don't act like they're precocial.  They don't immediately or at least very soon after hatching trot around following their mother?  But they imprint as if they were precocial.  

A toaster???

This did not sound right at all.  Something is amiss.

Therefore just in case  I had missed something as large as classic precocial imprinting in raptors....  I mean what if an urban eyass hatched, looked up, and saw a human at a window?  Or looked down at the street and saw a human before she saw a parent?  This had never happened so I'm even more suspicious about the comments?  Raptor educators have to train, they have to take exams...

 This could not possibly be true of Red-tails!  Wait!  Perhaps it was just a helper speaking out of turn?  Or perhaps I heard it incorrectly?  Will an owl imprint on a toaster.  If that were true, perhaps that's how "toaster" entered the conversation then?

But when in doubt about Red-tail behavior no matter how sketchy we think what happened was, or how bad our ears might be, we have the wonderful luxury of sending off a missive to our Red-tailed Hawk expert, Mr. John Blakeman in Ohio, which is exactly what I did.  And as usual he sent back an immediate reply, which follows...
  
Donegal,

No, hawks do not imprint in the classic manner of geese or other waterfowl. That textbook behavior isn't how eyasses connect and identify with their parents. If it were, the eyasses would be flying behind the tails of the haggards all summer, in the manner of imprinted ducks swimming  behind the tails of the female parent.
 
Eyasses will, however, become "imprinted" to humans who take a hawk from a nest and then raise it. It's a long story with many details, but in essence the young hawk connects with and identifies the human as its source of food.

 The human can't fly or otherwise allow the progression of summer-learned normal hunting behaviors, so the young hawk becomes permanently mind-scarred, focused solely on the human.

 (An imprinted hawk can never be restored to normal psychology and independent behavior. In my book, I'll tell the story of "Goldie," an imprinted Red-tail I cared for for 13 years.)
 
But no, none of that happens when eyasses naturally connect with their parents in the nest. The imprinting that so occurs is rather weak and quickly terminated when the eyass fledges and has to learn to hunt and kill for itself in a few weeks of summer.
And no, a newly-hatched eyass seeing a big, lumbering human on the other side of a ledge-nest window is not going to "imprint" to that person. It's not whatever the hawk first sees that is moving; it's whatever first and continues to feed the hawk that it connects with.
--John Blakeman

Many thanks John, a splendid clarification as usual.   I thought perhaps I was loosing my mind.  How could I  possibly have missed that somehow Red-tails were precocial at least in imprinting and I never noticed??? 

Speaking of which, while investigating the matter,  I ran across the chart below. It breaks down Precocial and Altricial into finer categories.

As Red-tailed Hawk eyasses are hatched with down and have their eyes open they are considered Semi-altricial 1. 

 While owls are hatched with down but have their eyes closed when hatched, they are considered Semi-altricial 2.

Check out the chart.  I found it fascinating. 

(What is a Megapode?  It is any of 12 species of chickenlike birds (order Galliformes) that bury their eggs to hatch them. Most species use fermenting plants, kind of a compost approach to produce heat for incubation, but some use solar heat and others use the heat produced by volcanoes.)

Characteristics Of Nestlings
(modified from O'Connor, 1984)

TYPE OF
DEVELOPMENT
DOWN
PRESENT?
EYES
OPEN?
MOBILE?.
FEED.
SELVES?
PARENTS
ABSENT?
EXAMPLES
Precocial 1
Yes
Yes
Yes
Yes
Yes
Megapodes
Precocial 2
Yes
Yes
Yes
Yes*
No
Ducks, Plovers
Precocial 3
Yes
Yes
Yes
Yes
No
Quail, Turkey
Precocial 4
Yes
Yes
Yes
Yes/No
No
Grebes, Rails
Semi-precocial
Yes
Yes
Yes/No
No
No
Gulls, Terns
Semi-altricial 1
Yes
Yes
No
No
No
Herons, Hawks
Semi-altricial 2
Yes
No
No
No
No
Owls
Altricial
No
No
No
No
No
Passerines
... t = Precocial 3 are shown food.
.....*= Precocial 2 follow parents but find own food.
 

Many thanks to Stanford for the dandy chart, for more on the topic go to...
http://www.stanford.edu/group/stanfordbirds/text/essays/Precocial_and_Altricial.html

Then I had another rather mind expanding experience today.  I'd gone out the back door during the gloaming and saw one Hummingbird run another off the feeder.  Not unusual they love going after each other.  But then the winner sat on a small branch of the Magnolia near the feeder and just continued to sit.  Then he went back to the feeder.   Drank.  Then went back to a branch and sat. 

This hummingbird doesn't look like a Ruby-throat to me at all and that is the only species that is found in the Eastern United States normally and...wait just a minute! That hummingbird looks dark purple..

... I went for my camera. Took pictures, in the dusky light. These are going to be BAD.  Went back in, pulled the card, stuck it into the computer and I looked... fully expecting the bird to be a Ruby-throated Hummingbird after all, due to a trick of the light, but.....nope.

Okay, the camera says his back is dark green and his head is black.  Is there some shot which isn't of his back?
He's out of focus but blocks of color are evident.  I wonder if he is still resting, drinking, resting, drinking?  I grab my other camera and go out.

Nooooooo, I forgot to disable the flash on this camera. It isn't really as dark out as it looks, in actuality the same light as above, but the camera just adjusted the aperture as it knew it was going to flash even though I didn't.  

Sorry little guy. Thank goodness he is still going about his business.

 I go back in the house to let him drink, rest, drink, rest, until he goes into torpor.  He has very likely just come on a very long trip.

I grab Peterson's Field Guide to Eastern Birds.  Sure enough he is a vagrant.  He is a Black-chinned Hummingbird and ordinarily he wouldn't be any further east than Texas.

That is a whole lot of extra little hummingbird wing beats.  No wonder he's hungry and tired.  I'm certainly glad the feeder was up.  

Plus my fingers are crossed for him.


Donegal Browne

Tuesday, May 13, 2014

A Pale Male Sunday Update from Stella Hamilton! Frannie The Sand Hill Crane or Was It Her Mate? And the Birds at the Bywater!

 Photo courtesy of palemale.com  
 The flapping has started though the hopping is mostly yet to come.

A PALE MALE UPDATE FROM STELLA
 

A few of us, including some from the "new generation" of hawkwatchers gathered at Hawkbench this past Sunday to watch Pale Male , Octavia and the three babies . They had a big audience.  Some looking through binoculars , but most looked through the Stellascope.  I just love to watch the expression on people's faces when they see a hawk on the nest with their babies for the first time . 

Come on you know that look ." Oh wow!" 
Followed by a jaw drop?

One of the highlights of the afternoon was sometime around 5pm , when  Pale Male chased an egret away from the nest . The Egret headed toward the Ramble and both he and Pale Male disappeared for a minute . We later saw Pale Male emerge from the Ramble , being chased by a kestrel . So that chase went on for about 5 minutes , with Pale Male being dive bombed on his royal blond head every few seconds by the kestrel . Then it was quiet again . 

Octavia had been pretty active herself.  Stretching  her wings and kiting above us as if she simply wanted to have fun . Both she and Pale Male would disappear for a while, leaving the nest and the kids seemingly unattended .

 I wondered if we would see a feeding ? Sure enough about 15 minutes past 7, Pale Male flew around the tree tops on 5 th Ave  with a massive partially eaten rat . It was so huge he looked as if he was having a hard time taking it to nest ! Octavia had positioned herself on a corner of the "Linda Building" as if ready to assist .  So Palemale flew with it over the trees , then to one of the lower corner balconies of the "Dr. Fisher Building" , then to "Woody Allen Building", then finally to nest!  Boy , did we all cheer !  Octavia followed right behind him, and started to pull meat to feed to the babies . 

So glad we waited. It was a wonderful afternoon.

Many thanks Stella! Keep them coming!

Next Up, Checking in with Frannie the Sandhill Crane

As many of you will remember Frannie is sitting on a nest atop a dry spot in small pond.
 But when I went to check on her on Sunday, something was odd.  I couldn't put my finger on it at the time but note her head is at a slightly different angle than usual and her body appears bigger and maybe flatter somehow?
After further scrutiny I decided this might not be Franny at all but rather her mate.   Or perhaps  there are colts under her which make her body look different?

Hmmm, maybe if I go away I can sneak another look later and look for more clues as to what may be different today. So I decided to walk a short distance to the bridge which spans a bywater of the Sugar River as there appeared to be dozens of swallows zipping around at major speed.

And zip they did. 
 There were several Tree Swallows.
 And even more Cliff Swallows, identified by the head patch and the rump patch when she swerved past.

Also in the mix, there were migrating warblers. 

A Yellow-rumped Warbler

See.   He actually does have a yellow rump.
Not to be confused with a Yellow Warbler, which has a yellow everything.
 Plus the day brought,
A pair of conversing Rose-breasted Grosbeaks.
 Plus at the banding station, a Chestnut-sided Warbler, for those who have never seen one.

But what about Frannie/or her mate you ask?
 While I was attempting to photograph Warblers and Swallows, she/he watched, head up, the whole time.

Then when  I drove past, turned around and came back I could see she was standing up looking down.  But in a nanosecond, she plopped back onto the nest before I could get a look at anything. 

 Well, maybe next time.

And last but not least the little pale mystery bird.

When I first pull into the driveway, I always scan the trees for the Cooper's Hawk and check what is up at the northside bird feeder.  From my position I was looking at a three quarter view of the feeder, back and side.  Well see was spraying everywhere and the House Sparrows were being chased off the feeder, by a bird I could not see.  So I got out of the car and quietly tried to get to the other side of the feeder.

I got to the other side of the feeder and the seed quit spewing out and a pale sparrow sized bird flew to the far side onto the fence.  When I turned back this bird was sitting looking at me.
Anybody have a guess?  

Bottom bill appears to be at least partially yellow.  The little of the wing that can be seen appears to have more pigment than the front of the bird and there might be a ghost of a white throat there as well.  

Suggestions?