I’ve been following the reports of hirundines – that’s the Sand martins, House martins and Swallows – arriving for the last week or so, itching to get out and find some for myself. Finally today I plodded, slowly and still having trouble walking in a straight line, over to the other side of Cardiff Bay, and my stumbling was rewarded by the sight of at least half a dozen Sand martins checking out the holes in the walls of one of the old harbour docks as potential nesting sites. A couple of pairs looked like they were getting quite cosy.