🚀 go-pugleaf

Interesting question. I often watch Harriers & Kestrels. Harriers really are
sailplanes that do not really hover, they can drop their forward speed to
almost nothing for short periods (as can Kites) but I would'nt call it a
true hover. Kestrels really do hover in exactly the same way as Kingfishers,
by beating their wings which are  held at the perfect angle of attack to
negate forward motion. As mentioned Redtails sometimes hang in mid air
without forward motion but that requires a strong wind & is really a
controlled dive at a speed that exactly matches opposing wind velocity.
Roughlegs can also hover in the same manner as kestrels, no wind required,
but it looks like hard work for them. John J. Collins <jjcbird@banet.net>
wrote in message news:3803DEF7.F4368B7C@banet.net...
> Tina Harrup wrote:
>
> > Was watching David Attenborough's "Life of Birds" on video the other
day - one
> > of the BBC's mega natural history productions.  One sequence showed an
African
> > Pied Kingfisher hovering above water and Sir David stated that it was
the
> > largest bird in the world to be able to do this.
> >
> > Indeed, it is a fairly big bird and I've seen a fair few doing their
hovering
> > trick in my time.  And wonderful they are to watch too.  But I've also
seen a
> > couple of large raptors doing the same over the Hungarian plains:
> > Rough-legged Buzzard and Short-toed Eagle to be precise.  Both of these
are
> > considerably bigger than a Pied Kingfisher.
>
> > What could the Beeb mean?   Maybe it meant that it was the largest bird
able
> > to hover over water in still air.  But I thought it was rather
misleading and
> > these documentaries are usually very well researched.  Or have I missed
> > something.  Or just being plain pedantic.
> >
> > Tina
>
> Hmmm.  Something is amiss here.  The Pied Kingfisher is merely a medium
sized
> kingfisher (25-29 cm in length and weighing a little over 69 grams).  The
Giant
> Kingfisher (also living in Africa) also hovers when fishing (though less
so than
> the Pied) and is twice as big (43-46 cm in length, more than 338 grams in
> weight).  I can think of many birds that can hover (without the apparent
aid of
> wind) and all the kestrels are among them.  Others are Red-shouldered
Hawk,
> Black-tailed Kite, Northern Harrier.  I say "apparent" because in my
review of
> this topic in Ehrlich's "The Birder's Handbook" he implies that birds of
prey,
> including kestrels, require wind to hover.  I'm not sure I agree with
that.  Any
> other opinions out there?
>
> --
> John J. Collins
> Whitestone, NY
> "In the end we will conserve only what we love; we will love only what we
> understand; we will understand only what we are taught."  (Senegalese
proverb.)
>
>