Magpies were once quite scarce here on Portland.

Nowadays we see flocks of thirty five together not uncommonly, out of the
main breeding season.

The increase over recent years has been attributed to the increase in
traffic roadkills - bunnies, (we don't use the 'R' word here.. local
superstition dictates) hedgehogs, and other birds.

Likewise there has been an increase in Carrion Crow. We don't have the trees
for rookeries. Ravens remain few. One imagines they need larger breeding
territories.

Keith
Isle of Portland





"Malcolm" wrote in message
...

In article , Larry Stoter
writes
Mike Lyle wrote:

"Larry Stoter" wrote in message
...
[...]
If one pauses to consider ....

'Songbirds' and the 'usual suspects' - Magpies, Sparrowhawks,
Peregrines
have actually co-existed quite happily in Britain and elsewhere for
thousands of years. If there is now a problem, it makes absolutely no
sense to blame Magpies, Sparrowhawks or Peregrines. If there is a
problem, logically it must arise from something which is different now
from the last 10,000 years. And even a Sun reader should be able to
work
that out, possibly with the help of a few diagrams .... :-)

I understand the ecology of it makes predators the more vulnerable in
the prey-predator relationship. A decline in the numbers of prey species
will kill off predators; and predators can't increase at the expense of
prey. So a large population of predators inevitably suggests a large
population of prey.

That is the theory and, as far as can be determined by observation, the
reality in the vast majority of cases - as far as I understand it :-)

The point I was trying to make was that when things go wrong, 999 times
out of 1,000, somewhere along the line, human activity is to blame. It
is also important to appreciate that there is a big difference between
Mrs Cholmondley Bigbucket reporting that Magpies are killing all the
Songbirds in her back garden and a scientific study. While anecdotal
evidence might be useful, it can be very misleading and result in people
jumping to all sorts of erroneous conclusions.

I can remember receiving a letter from a lady in Surrey who said that
magpies had killed *all* the songbirds in her garden and now she only ever
saw magpies and no other kinds of birds ever visited her garden. I was
sorely tempted to ask her what she thought the magpies were now feeding on
if there were no songbirds left!

--
Malcolm