Jos Stratford said:A second point is that since feeding is so widespread in the UK, probably it's only a question of jumping over a couple of fences and hedges to reach the next well-stocked larder.
I have feeders which 'self-fill' and can hold many kilograms of food, thus lasting 2-3 weeks if need be (but in reality I think the birds would disperse and find food anyhow).
Jos, what are these fantastic self-filling bird feeders that you talk about? Please give us more details. Do they stay full even after a prolonged absence in the middle of winter, which I seem to remember you had early this year?
I agree entirely about so many people feeding birds that the birds can just move to a station nearby. I can see one all year round feeding station a few gardens away from my house, I'm sure there are others nearby that I don't know about.
An interesting and obvious point that you make, about natural food resources running out and the birds just move on till they find something else.
As to the birds forgetting my feeders because of them going empty, I haven't found that a problem. Even after our three week gap last summer, once I filled them up again, all the species were back soon enough.