The reason why more BARC birds are being recorded ...

To: Birding Aus <>
Subject: The reason why more BARC birds are being recorded ...
From: L&L Knight <>
Date: Wed, 19 Dec 2007 18:08:48 +1000
The number of rarite reports accepted by BARC (n) = x - a - b - c - d

x is the number of rarites that actually visit Australia
x - a is the number that people perceive [see or hear], in many cases without consciously being aware of the birds x - a - b is the number that people observe [they are aware of the birds]
x - a - b - c is the number that people correctly identify
x - a - b - c - d is the number of correctly identified birds that are reported to BARC with sufficient detail to become an accepted sighting

The question is whether x is greater than 1% of n. Rarites that turn up to twitcher hotspots - eg WTP, BBO, Penrice, Ash Island, Buckley's Hole have a high probability of being observed and identified. Rarites that turn up in areas not on the twitching map - eg Burren Junction are generally not observed.

The reason more rarites are being reported is that more twitchers have telephoto lenses and are reporting sightings on Birding-Aus etc - the following article provides a picture of the situation in the UK this year ...

Regards, Laurie.

A very British bird boom
This year more rare birds have been sighted on our shores than ever before. And, as David Randall finds, it's our very own hi-tech twitchers that we need to thank
Published: 16 December 2007

< snip>

The interesting thing is that the "bird of the year" came and went without being seen by a twitcher - an exhausted Yellow-nosed Albatross turned up in someone's yard, was taken to a rescue centre, photographed and released the next day ...


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