I get out there and engage them every day mate , with traps , guns and poison in season . Its not about sport its about getting rid of as many as possible . Grey squirrels are a major pest to forestry and agriculture they compete with hole nesting birds for obvious reasons they also eat eggs and chicks as well as the red squirrel problems . If you have shooting rights anywhere get out and kill as many tree rats as you can . The best gun ive found for the job is a silenced mossberg 410 pump action . Start the year drey poking in February then follow this with baited traps then follow this with warfarin poisoning , start one end of your shoot and work across it 1 wood at a time and if you can work with your neighbours with it and you'll make a difference . As for calls the primos 3 in 1 works and if you use the squeeker call it works for muntjac . What about a national squirrel day instead of pigeons ?