Wednesday, August 09, 2006

Central Park: Sub-adult Red-tailed Hawk

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Sub-adult Red-tailed Hawk
Central Park, NYC near Winterdale Arch
Image by BEN CACACE
(click image above / additional photos below)

A young Red-tailed Hawk showed up in Central Park this summer. On the 4th of July this hawk was photographed by Lincoln Karim. Lincoln has posted 10 photos of this one year old hawk which has just started to grow in its adult red tail feathers.

A Red-tailed's juvenile feathers drop out as the adult ones grow in after its first year. Lincoln's photos demonstrate this is a first year hawk and is considered a sub-adult. According to the books, adult plumage is acquired in a hawk's second year. A sub-adult may retain some juvenile wing and tail feathers before its second year molt.

The tail feathers (retrices) of a Red-tailed Hawk are numbered 1 through 6 starting from the center making up a total of 12 feathers. Each feather is paired symmetrically and preceded with the letter ‘r’. The r1 tail feathers are the centermost ones. When the tail is folded these feathers are visible when viewing a hawk from behind. The r6 tail feathers are the outermost ones and are visible on the folded tail when viewing a hawk from the front.

The tail feathers on this hawk, from the 4th of July photos, appears to have only adult r1s & r2s.

A few weeks after Lincoln's photos I spotted this hawk on the 18th, 19th & 23rd of July. At the time of these observations the r1, r2 & r6 tail feathers were red. The r6s were much shorter than the r1s & r2s.

I spotted this hawk again on August 4th which is when I took these photos near Winterdale Arch east of ‘Locust Grove’. In these images both the r3 & r4 feathers have grown in since the 23rd of July. The only juvenile tail feathers appear to be the r5s. Even with binoculars I wasn't able to pick up other juvenile feathers.

Will these r5 feathers remain until this hawk molts again next summer?

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Click images for an uncompressed view of the tail

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3 Comments:

Yojimbot said...

based on the progress of its molt, how old would you estimate the rth's age at?

Ben C. said...

yojimbot,

This would be a "one year old hawk" born sometime last summer. This is a hawk that is not that leary of the approach of people.

I wonder how 'tame' this age of RT is in the wild?

Anonymous said...

My guess is it's either Maggie or Charlie - came back to C.P. hungry.