Re: High-flying Swifts

To: Stephen Ambrose <>
Subject: Re: High-flying Swifts
From: Andrew Taylor <>
Date: Thu, 13 Mar 1997 18:58:37 +1100 (EST)
 Lawrie Conole wrote:
> > 
> > Can't answer this one; but I guess they'd be snap-frozen if they were more
> > than a few thousand metres up.

Alerstam book "Bird Migration" refers to an experiment in Sweden where
researchers where able to measure altitude of Common Swifts on their
return flight of several hundred kms to their nest.  In clear weather
the average altitude was 2300m 10 of 50 swifts had flown
to altitudes over 3000m.  The highest was 3600m.

In the discussion of migration flight altitude Alerstam mentions as
an extreme a plane collision with a Ruppell's Vulture at 11,000m.

The reduction in partial pressure of oxygen at higher altitudes is less of
a problem for birds because of the efficiency of their respiratory system.
To some extent the cooler temperatures at higher altitudes can be helpful
to migrating birds because water loss is reduced.  This may be relevant
to Swifts.

Andrew Taylor

<Prev in Thread] Current Thread [Next in Thread>

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the birding-aus mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU