wrote:
>
> I'm amazed that the UK story about the House Sparrow decline
> does not mention Sparrowhawks Accipter nisus.
>
> They got that name for good reasons. And the decline stated
> in the article corresponds well with the rise in the UK
> Sparrowhawk population which had crashed due to DDT etc.
>
> When the Sparrowhawks returned to London in the 1980s I
> found the first pair on Hampstead Heath. Soon there were two
> or three breeding pairs with 3 to 5 young per nest and small
> birds were much quieter. I calculated from the published
> data that they would be consuming thousands of small birds
> each year. I saw them hunting and in street trees outside
> our flat at least 3 kms away from the nest sites.
>
> We bird lovers can overlook what avian predators can do. I
> did an analysis of the decline in the Common Bronzewing
> population in the City of Bayside. It coincided with some
> Pindone oats poisoning of rabbits, mulching over areas with
> seed falls... But I've only recently realised that our
> Collared Sparrowhawks will take birds as large as
> Bronzewings (see the Pizzey and Knight field guide).
>
> I've yet to check the stats. and will try to let you know my
> conclusions.
>
> But I certainly do not start with the prejudices about
> predator/prey relationships meaning that predators cannot
> exterminate one of their prey species. Look at what Homo
> sapiens has done.
>
> Michael Norris
>
Hullo Michael,
Thanks for comments - just what I hoped for...
On the basis (totally inadequate) of 6 weeks in England Sept/oct 2000,
both House and Tree Sparrows (and buntings and finches) are very thin on
the ground everywhere. We didn't see much in the way of birds at all in
inner London, bar far too many very mangy pigeons, and park ducks. The
kind Park Ranger in St James Park (he ran after us to give us a list of
park waterfowl) said he thought it was because of the very thorough
netting over all ledges and crannies on older buildings - an anti-Pigeon
measure. As well as the fact that there are now very few horses in the
streets - sparrows used to rely on grains spilt from nosebags or passsed
in horse-dung.
We certainly saw plenty of Sparrowhawks in England, but birdwatchers
we met were inclined to blame hedge removal for small bird decline.
After all, there used to be plenty of both Sparrowhawks and Sparrows in
Britain but the Sparrows have only declined fairly recently.
I was quite surprised at myself immediately after our return to
Melbourne - I saw the usual House Sparrow gang in the supermarket
carpark, and was quite glad to see them! I doubt if I saw more than half
a dozen in England.
All the best,
Anthea Fleming
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