Fake conservationists' killing again.
 

Being as red squirrels were common throughout the country before the
greys were introduced I would imagine that they were present in the Kew
area at that time. Of course, they are unlikely to to return to the
area while greys continue to proliferate. Perhaps you are unaware that
the greys were introduced to the UK from North America and that they
are responsible for the decline in the numbers of the indiginous red
squirrel.

Sadly your personal experiences or predictions are hardly a solid base
for your argument.

I have to ask, are you seriously suggesting that rats should not be
culled at every oportunity?