FFS just a new member posting a picture and asking a harmless question.
Yes we all know how great those that believe in culling are. Try keeping your brilliance to yourselves unless asked then I won't stumble over a load of old blox by accident, again - I don't care.
Since OP didn't specify the limit to which the discussion might extend - and presumably didn't ask anyone to do it for him - I'll assume that those of us who wish to continue what is an interesting and relevant discussion, can do so.
Grey squirrels and Red squirrels basically occupy the same ecological niche. Before the introduction of Greys into the UK Reds were mercilessly persecuted, so much so that they had to be reintroduced into the UK from continental Europe. The current narrative of "investations of nasty, introduced Greys" vs "loveable cute native Squirrel Nutkin" is basically nonsense.
The persecution of certain species in less enlightened times is hardly an argument for the acceptance of invasive species today.
There is no such thing as UK red squirrels. Original (for want of a better word) 'UK' red squirrels are the same genus (Sciurus vulgaris) as those reintroduced to the UK from European populations. They are all Eurasian red squirrels. From an ecological point of view, I'm not sure how it's possibly to arrive at the idea that the introduction of pox-bearing greys was anything but a bad idea, when they decimated the UK population of reds.
Likewise, the previously (and still, in some quarters) persecuted European red kite (Milvus milvus) has largely been reintroduced to the the UK from sources in Scandinavia and Spain. It is the same genus as the 'original' UK red kite.
And finally, what if we applied the argument about historical human intervention to the invasive signal crayfish, here in the UK? These are threatening not only waterborne creatures, but the very fabric of our rivers. Do we just accept them because, since the industrial revolution, we've neglected to look after our rivers?
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On a lighter note. They're introducing pine martens to the Forest of Dean - known amusingly, as the Dean Marten (sic) - not far from me in Gloucestershire (UK). The efficacy of the reintroduction of the marten, in relation to squirrels, is that the reds are so light that they can escape it, across branches that the heavier grey cannot negotiate. The reintroduction of the marten is a perfect solution to the grey/red squirrel problem.
If only there were a natural predator (legislation and the long arm of the law is failing us) for the British gamekeeper, our eagle and kite populations might then be more secure!
In answer to the original question (I got there in the end). I'm not sure tame, so much as emboldened, is the right word for greys in cities. One once ran up the leg and arm of a friend while he was enjoying the spring sunshine and eating lunch - the squirrel made off with a decent portion of egg mayonnaise... I guess it made a change from nuts.
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