Thursday, January 28, 2010

Tulsa Nest Question, Blakeman on Red-tail Skin Pigment, and the Innocent Bystander Burnt Bird


Sally of Kentucky has sent some screen captures from the KJRH TV web cam for us to scrutinize.
Here is her email--

Dear Donna,

As I know you have heard, Kay and Jay have been seen working actively on what appears to be a new or alternative nest site on another tower in the area of the KJRH tower nest. We have not seen much if any change in the nest they used last year in the brief views of it which we have been allowed. Because the weather cam has not been trained on the nest for long periods of time with any regularity, we cannot observe for long periods if they are visiting that nest, and if so how often.

The few occasions we have had a longer viewing period no hawks were seen. Our only guide right now is the occasional on the ground observation of them and the brief glimpses of the nest which we try to analyze for subtle signs they have been working. Yesterday, however, Catgirl observed both hawks on the KJRH tower and Jay actually up on the nest working, though, he was not observed carrying anything to the nest. Kay was on an adjacent part of the tower apparently ignoring his efforts. We think the nest looks move-in ready, so is it possible that they will not add much to it this year, that they are happy with its present state, but feeling the need to do something are spending time on the alternate site?

That site at this point is no where near thick enough to have a nest this year. We are looking for hope that they will return to the KJRH nest this season! What do you think? Would Blakeman have time to comment? I have attached a view of the nest from this summer and one from a recent capture for you to compare. I apologize the quality of my screen captures is not very crisp. Its all I have! Thank you.


I'll ask John Blakeman to take a look. In the meantime, if the secondary nest is disorganized and doesn't have enough material, and remains that way, it is likely just that, the secondary nest that is seasonally built so the female has a choice.

Even Pale Male and Lola do it and they've ended up nesting on 927 for years anyway.. They've been observed at various times moving twigs onto the Beresford over on the Westside, but it never gets to nest-ness. If the secondary Tulsa nest begins to really look like a nest then it might be a true option instead a matter of form.

As you probably remember some people believe that when the evergreen twigs appear on a nest that the choice has been made. I don't know for sure that's true for all pairs but some folks swear by it.

When have Kay and Jay started to lay in past years? I know they're earlier than NYC. PM and L tend to take to the nest with a clutch usually within the first week of March, with first observed copulation the end of January, or beginning of February, approximately a month of copulation before sitting. So as Kay and Jay are earlier, they might already be copulating. Therefore this would be the big time for them to be doing as you say, nest-eration.

In the past has Jay been the one doing most of the building or does Kay do a lot too? It seems to differ according to pair. Lola is bigger on rearranging than actually bringing twigs though Pale is pretty big on arranging as well, he’s the one I most often see bringing twigs. Lola is the one who gets the bark for the nest bowl. I've seen both getting the dry grass.

Don't worry about the lack of photo sharpness, it’s super to have the documentation for comparison.

Speaking of Ohio Hawk Mavin John Blakeman, here is more about the odd and interesting variation of skin color in young Red-tailed Hawks--

Regarding skin pigmentation in hawks. You are absolutely correct in noting that the wild prey of hawks includes the food contents of the prey’s stomach and intestines. These rodents and birds eat seeds, vegetation, and insects that all have colorful (and healthful) carotenoids.

These plant pigments are absorbed by the consuming hawks, yielding the intense, saturated skin colors of feet and ceres.

As mentioned, however, there are a few first-year wild red-tails who don’t have yellow feet or ceres. After having trapped many dozens of wild red-tails over several decades, I’ve noted that leg skin colors vary from very intense yellow, to a hint of yellow, on to a rather meager blue-gray in a few birds. Is this variability purely genetic, or does it reflect a preferred food source that doesn’t eat many colored vegetables? I don’t know, but I think it’s probably genetic. A few birds apparently can’t so easily absorb or utilize these plant pigments.

Are these birds then less healthy, less likely to make it through their first year? I don’t know—one of many dozens of red-tail questions that need answers.

–John Blakeman

Well, John, yet another fascinating field study and dissertation waiting to happen. Do you happen to know if there is any particular area in which there are more of these non-yellow footed youngsters than others? Of course if there were we still wouldn't know if it was genetic or food related or both but it would be a lot easier to figure it out if there were such an area or grouping of hawks.

Contributor Ken Zommer of Chicago sent in this tale of one tough Red-tailed Hawk and a plane crash--

From The Chicago Sun Times January 26, 2010,CST-NWS-SNEED26.article

BY MICHAEL SNEED Sun-Times Columnist

The burnt bird . . .

There's always a story behind a story.

This time a bird is involved.

An unlikely bystander was injured by the fireball caused by a Saturday night plane crash in Sugar Grove, which killed two people on board.

The bystander: a red-tailed hawk.

The raptor rescue began with a report of "a bird on the ground" near the wreckage site by Kane County Animal Control.

Apparently perched in a nearby tree before the crash, the roasted raptor was found standing in the snow when firefighters arrived.

"She's alive, but it was close," said Flint Creek Wildlife Rehabilitation founder Dawn Keller, who triaged the hawk for 75 minutes at her group's Barrington rehab site.

"There is not a single feather that's not burned off of that bird's body," she said.

"I've never seen anything like it. Quite honestly, I think it's a miracle. I can't believe she's alive," said Keller.

"We now call her 'Phoenix' after the mythical bird which was consumed by fire but rose from the ashes.

"I have treated her every four hours since then," she told Sneed.

"All that's left is the really fine down feathers close to her skin that provide insulation and waterproofing -- and these four- to five-inch long charred black shafts that used to have feathers on them."

"Every inch of exposed skin was charred black -- she just smelled like a fire -- the top layer of skin on the feet hanging off," said Keller, who had to gently remove the dead skin and apply burn cream before bandaging the bird.

"But she's doing well, I mean she's standing. Her feet are all bandaged, but she's standing. She's not eating yet. She's on fluid therapy, pain meds and antibiotics," said Keller.

• The big question: Could the bird have caused the crash?

"There's no chance this bird could have caused this plane crash," said Keller.

"The crash happened after dark, which means she was already sleeping for the night. If she got sucked into the propeller or engine she'd be dead. She was just an innocent bystander who was in the wrong place at the wrong time."

• The hawk's future? "Her release to the wild depends on her vision. It really comes down to her eyes at this point.

"The veterinary ophthalmologist said her outer eyelids are damaged, but they did protect the cornea. Now we need to treat the eyelids to save them."

• Prognosis: "We expect the bird to survive. Only time will tell if we can release her -- it depends on her eyelids healing correctly," said Keller. "If the bird can't be released, we'd try to make sure she is used for educational purposes -- like showing her at area schools."

Donegal Browne

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