dopey greenfinches

For the last few years at this time of year, some of our greenfinches behave strangely.  They fluff out their feathers so look bigger than normal, and just sit about - to the extent that you can get within 12inches of them before they move, and other birds like young starlings literally knock them off their perches.  They're also easy prey to cats.  Can anyone explain what's going on?

Also, we have a ring tailed parakeet that has just appeared in our garden.  I know there are wild communities of these birds further south - we're near Worcester!  Is anyone aware of wild parakeets this far north or is it likely to be a domestic escapee?