Sparrow decline in Canberra too.

To: <>, "Peter Woodall" <>
Subject: Sparrow decline in Canberra too.
From: "Philip Veerman" <>
Date: Fri, 21 Apr 2006 16:29:16 +1000
Thanks Peter for the suggestion. Yes there has also been a decline in abundance 
of the House Sparrow in Canberra, throughout the years 1981 to 2002 for which 
consistently compiled data exist from the Garden Bird Survey (GBS) that has 
been run by Canberra Ornithologists Group (COG). One thing to be aware of 
though is trends such as this can only be discussed sensibly in past tense. 
They can change at any time. Pity I can't include the graph from my book in 
here. For years 1 (1981-82) to 14 (1994-95) the Common Starling and House 
Sparrow (respectively) occupied position 1 and 2 in the abundance lists (out of 
130 to 147 species recorded per year). Actually the House Sparrow was in very 
slight increase for the first six years (probably not statistically significant 
though) and then fairly steep decline. In year 15 the Sulphur-crested Cockatoo 
replaced it to become number 2 species. As at year 21 (2001-02) the Common 
Starling and House Sparrow (respectively) occupied position 5 and 6 in the 
abundance lists. In 2003-04 the House Sparrow was down to ninth (ref: COG ABR 
in CBN). The Common Myna has gone above the Starling, suggesting a very strong 
link there but the reason for decline in the House Sparrow is not so clear. 
Probably many factors acting together. Not something we need to worry about too 
much at this stage. The continuous monitoring of a bird community shows a lot 
of variability not just between increasers and decreasers but between stable 
and not stable species.


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