Re: Tail feathers

[Ronald Orenstein <ornstn@inforamp.net>]

>1), is looseing the tail feathers a defensive move?
>
>2). Are tail feathers really needed to fly? 

Yes to the first question, no to the second - though a tailless bird cannot,
perhaps, maneuver with quite the same ease it can fly perfectly well (though
see Matt Troutman's more detailed message citing work done on the role of the
tail in flight).  Note, of course, that in some birds (eg some birds of
paradise and hummingbirds) there is strong sexual dimorphism in tail size,
shape and structure, though I know of no studies on how this affects the
flying
abilities of the sexes.  An interesting case is the Bateleur Eagle of Africa,
in which the tail of the adult is much shorter than that of the immature; this
may give the adults greater ability to perform acrobatic flight maneuvers
typical of this species.

In many birds dropping the tail feathers presumably serves the same
function as
breaking off the tail in many lizards - in fact a frightened bird can, in some
cases, undergo a "fright molt" in which many feathers can be lost. 
--
Ronald I. Orenstein                           Phone: (905) 820-7886
International Wildlife Coalition              Fax/Modem: (905) 569-0116
1825 Shady Creek Court                 
Mississauga, Ontario, Canada L5L 3W2          mailto:ornstn@inforamp.net