Flying geese

Last Tuesday at The Ponds the air was full of birdsong, a very good reason not to wear an iPod in one's ear as some people do, though I must say, I've never seen pond-walkers do this. Among the calls came the goose's familiar 'honk' along with a couple of warbeling sounds (trumpeting?) I've never heard before. Two of them were flying toward the ponds and as they went over they presented this picture.