Telegraph: The swallows’ return to British shores each year symbolises the passing of winter and the approach of summer. But in a sign of the blurring of the seasons brought on by climate change, one of the birds has this year shunned migration to Africa and instead spent all winter in Britain. In what experts say is the first documented evidence of the species "overwintering" here, a solitary swallow has been monitored from November to the end of February in a village near …