Re: Swifts in Carwoola

[martin butterfield <>]

Following my report earlier this evening an observer commented that they had seen a single swift over their yard.  After a good description of swift jizz they concluded "... do they fly solo or would this one have been a stray from a nearby
out-of-sight flock passing by? I thought they flocked!"

The attached document shows the distribution of "flocks" of swifts reported in 28 years of GBS.  Clearly reports of 1 or 2 swifts are not uncommon.  There are enough references in HANZAB to 'single birds' to suggest that some birds may be 'loners' but possibly this simply reflects that relatively dispersed food resources lead the more typical large flock to be dispersed when passing over a small area such as a GBS site..

At a more detailed level - and possibly of interest in view of recent posts about counting flocks - once a flock is greater than 5, there is a distinct digital preference for numbers ending in zero.  Given the speed at which these birds travel it is not surprising that observers round them to the nearest 10.

Martin

On Fri, Mar 19, 2010 at 6:40 PM, martin butterfield <> wrote:

Some smoke is being blown up from the SE - presumably from one of the many hazard reduction burns listed on the RFS web site.  Some woodswallows and the occasional Swift were cruising through this, as reported by a resident on the Widgiewa Rd ridge.  They were unobliging in visiting my GBS site (about 1km NE).

100319 Size of swift flock.docx
Description: MS-Word 2007 document

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