We had gone to Lake Kussharo in Hokkaido, Japan, to photograph Whooper Swans. On this particular day, however, the swans were muddy and decidedly unphotogenic. With the temperature around –25°C, I wandered the grounds instead and noticed something far more interesting: Long-tailed Tits and Marsh Tits were taking turns nibbling at the tip of an icicle.

I set up my tripod and began trying to photograph the behavior. The tiny birds moved far too quickly to follow in flight, so I drew on my experience photographing hummingbirds. Rather than trying to track the birds, I focused on the tip of the icicle and waited for them to return to that exact spot.

It was a difficult situation—a gray day with very little light, a busy background, and a subject I wasn't actually focusing on until the instant it arrived. I spent four hours in the cold trying to capture that brief moment.

When I first uploaded the photographs to my computer, I was terribly disappointed. I put them aside for three weeks. When I finally looked again, I realized that although they weren't perfect, there were photographs in the series that worked.

Looking back, I think what made the strongest images work was the convergence of everything I could not have planned: the beautifully formed icicle, the subdued winter light, the tiny bird, and an unusual behavior most people had never seen. For a fraction of a second, all of those elements came together.