[RobSutton]

I think Little Egrets probably already have done and perhaps Cetti's Warbler too. Perhaps we also need to bear in mind that one possible senario of global warming is that we lose the influence of the North Atlantic Drift/Gulf Stream and end up with a climate similar to Nova Scotia. I'm not sure of the relative likelihood of this as a possibility or of the mechanics of it but the consequences of that could be even worse.

Closer to home we're getting a lot more butterflies up in the Dales because of recent warmer summers. Up here at Malham Tarn we had our first ever Speckled Wood last year and Comma as well and there are a number of other species which have colonised over the last 10 years or so.