Re: hovering diversity (was Re: Ornithurine diversity)

[jrc <jrccea@bellsouth.net>]

----- Original Message ----- 
From: "Erik Boehm" <erikboehm07@yahoo.com>
To: <dinosaur@usc.edu>; <mrowe@lifesci.ucsb.edu>
Sent: Tuesday, July 15, 2008 10:33 AM
Subject: Re: hovering diversity (was Re: Ornithurine diversity)


> The best lift is slightly in front of the ridge/bluffs (the front being 
> the side the wind is coming from), on the other side, you are likely to 
> get rotor and "trashy air"

Oops.  I wrote my response prior to seeing this.  Had I read this first, I 
probably would not have bothered  to respond, because Erik said it far more 
concisely than I did.
> You will observe hanggliders flying in the same general areas when flying 
> coastal bluffs. I suspect it is mainly aerodynamic considerations, not 
> hunting considerations that leads the birds to this position relative to 
> the bluffs.

I would say it is a combination of both.  There is not much point in 
hovering in areas that don't provide good hunting, and you'd only hunt in 
areas that have no exernal energy source available either when the hunting 
there is very, very much better than average, or alternatively -- when you 
are very hungry.
JimC