How many redtails at the Christmas Count?

Some of the Ramble Team just before starting out at the Christmas Count
Missing, among others, Bruce Yolton, who took this picture.
There is more info about the count, and more pictures on Bruce's site:
http://www.urbanhawks.blogs.com


To give you an idea of some of the complicated calculations that are part of a Christmas Count, and also an idea of the close scrutiny Central Park's redtails receive, here's a letter I just received from a knowledgable reader followed by my response:

Marie,

I saw the note on your blog [12/17/06] about ten red-tail hawks being counted
in the Central Park Christmas count today.

Would you happen to know what the adult/juvenile breakdown was
on that count?

I know of seven red-tails who would be about, the three nesting pairs
and at least one juvenile that has been hanging about. Two juveniles
if the one I have seen in the north woods is not the same as the one
who's been "playing" with Lola.

However, Bruce Y. and I briefly discussed last weekend whether there
might be another adult or pair who have claimed the area on the west
side south of the Pool.

rbs

I answered:

The ten was a very rough estimate decided upon at the compilation after the count. The total red-tail sightings of the seven separate reporting groups was 13. Since all but one of the sightings were of birds flying, it is assumed that some of the sightings were of the same bird. The groups must give times and directions of flight [i.e. redtail 10:16 am flying W] of all flying hawk sightings. Then if the times seem close and the direction works out, it's assumed it was the same hawk. So that's how it was reduced to ten. But it's perfectly possible that some of the others were also repeats. Also, many of the reports did not include info about whether it was an adult or immature.

In short, reporting flying birds of prey at a Christmas Count is not Rocket Science.