There are no head feathers yet (taken on May 29) - just fluff - which indicates they are nowhere near ready to fledge. By the time this eyass fledges, there will be no head fluff at all.
In addition to panting, they sit back and hold up their (huge!) feet for maximum cooling.
Today (June 2) Mom tried to stay cool by letting her wings droop down and away from her body.
I asked John Blakeman if this extreme heat causes distress for the eyasses, and whether their later hatching this year which will take them well into June's summer heat before they fledge will be problematic.
John Blakeman's reply:
"Take no concern for the excessive heat. Red-tails experience much greater heat in the deserts of the West. They are uncomfortable, but can handle it. In fact, they turn down their metabolism and body temperature, thereby requiring less food. But most of the food, now, of course, will be used [for the eyasses] to grow new feathers and muscles.
And the same for the summer heat. A matter of no real concern. The later fledge time changes really nothing. As before, all will be well."
... and their tail feathers - black and brown barred - are clearly visible.
The eyasses are completely unfazed by people photographing or watching them from behind their window. More than anything, they are curious to see what's going on back there. This eyass inched as close as it could to the glass...
... and this one stepped across the nest as Kay changed the lens, watching her every move.
Mom flew in several times, mostly staying only for a minute or so. She too was unbothered by visitors near the nest.
On one of her visits, she started to preen the eyasses, stripping out bits of fluff. They looked about as uncomfortable with this attention as any child would when a parent is fixing its appearance in some way!
This eyass couldn't completely swallow down the huge chunk of bird it had gobbled, leaving a morsel hanging out of its beak.
Their growth rate is phenomenal. It's hard to believe that only four weeks ago they looked like this!
Over the past week, their feathers have really started to grow through the fluff, and their appearance seems to change daily.
May 26
Just a few feathers poking through at the edges of the wings.
May 28
In addition to many more feathers on the wings, this eyass's bulging crop shows it had just dined extremely well.
The all-important flight feathers along the edge of the wings are getting longer.
May 29
Entering the Baby Vulture phase.
May 30
Seriously impressive wing feathers now.
May 31
Their bodies are now almost completely feathered, but their heads remain covered in fluff.
Another important stage they reached in the past week is vigorous wing flapping - wingercizing! - which is essential to develop the muscular coordination and strength needed for flying. At first, most of the flapping is done facing into the window with their backs to the street.
As they become stronger and more confident, they start to turn out.
When they face forward to flap with their backs to the window, they are closer to the time when they will start to flap-jump off the nest and onto the ledge that runs alongside.
Here's a timeline from May 22 - June 2 that shows many of the daily events on the nest.
May 22
The family still fits fairly comfortably on the nest.
May 23
No feathers yet.
May 25
Two days later, and what a change with feathers clearly showing! #3 in the middle had managed to snag a huge chunk of food, and was having difficulty swallowing it down. Mom is always ready for these occurrences, and if necessary, will pull the food out gently, and start over.
May 26
The eyasses show increasing curiosity about the world down below...
... and move closer to the edge of the nest.
May 27
Family time on the nest.
A lovely moment caught by Ari Rosenthal as T2 carefully feeds one of his eyasses.
May 28
Everyone has feathers now!
It started to rain that morning, and after breakfast the eyasses huddled closer and closer to stay warm.
Later that day, Kevin caught these amazing images of Mom landing on the nest, showing the aerodynamic control she has to put on the brakes and land softly beside the eyasses. What cannot be conveyed is the sheer speed of her approach when it seems that she must crash into the window.
May 29
T2 has everyone lined up nicely waiting to get fed.
Then Mom flew in with greenery...
... and the food service must have slowed down, so this eyass took matters into its own beak.
May 30
An alternative to waiting your turn is to grab from your sibling. Mom does not look pleased!
Standing tall to look out...
... and leaning forward.
May 31
Not much body fluff left now. #3 in the middle still has fewer feathers, and a slightly smaller head.
Because they spend so much time sitting down, the down on the backs of their legs has worn off.
The chestnut peach coloring on their chests is spreading.
June 2
Today, the first traces of head feathers are showing.
Each days ends with Mom settling on the nest, keeping watch as night falls.
May 28
May 29
June 2
Posts
Fascinating as ever. Thanks!
ReplyDeleteGreat coverage! As you know the NYU eyasses fledged like the Three Stooges over the weekend, landing in bushes, hiding atop very tall buildings, walking across the street, standing on a UPS truck (after leaving the windshield wiper of an NYU Security vehicle). NYU, Parks personnel and the local hawk fans really stepped up to the plate this year in terms of vigilance. Fingers cross that all goes well...Ann Feldman
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