Laura Erickson's For the Birds

One night in the mid-90s, I watched a saw-whet owl searching for prey in my backyard. He sat in a branch at eye level in a tree next to my back porch, his tiny feet the only parts of his body not in constant motion. Owls don’t move their eyes. To compensate, they swivel their heads this way and that. This little guy didn’t limit the swiveling to his head—his entire body twisted and turned this way and that as he checked out every tree and shrub and every inch of ground, his every muscle tensed, ready to spring into action. Every now and then his eyes met mine for a startling moment, but I held no interest for him. His entire being was on red alert, searching for any sign of a rodent. That little owl came to mind on January 8, when I went to Ashland, Wisconsin, to spend a morning looking for a very special shrike with Ryan Brady. We’d stop periodically and he’d scan the countryside for shrikes, and like that alert little owl, he looked every which way, never missing a thing. He quickly found the bird we were looking for, the oldest shrike known to science, whom Ryan had banded in March 2006. She bore a blue band on her right leg, along with her US Fish and Wildlife Service numbered band, and had a white band on her left leg. Last January I talked about Ryan and this particular shrike on “For the Birds” (http://lauraerickson.blogspot.com/2012/01/ryan-brady-and-oldest-known-northern.html), and this year I waited anxiously to hear if she’d returned yet again. On December 27, he found her again. Now she’s at least 8-and-a-half years old, which is mighty significant considering that the previous oldest Northern Shrike known to science was only 3 ½ years old. It’s not that shrikes are short-lived birds or that Ryan’s shrike is the oldest shrike ever to have lived—we can only be certain about the ages of birds that are both banded and then found again years later. Northern Shrikes breed in the far north where few researchers work, catching them requires a special trapping system not useful with other songbirds, and few if any banders before Ryan Brady have conducted long-term studies to try to track individuals from year to year. Following an individual shrike even within a season is tricky. Fluffy feathers cover their legs in most positions, making colored bands almost impossible to see except during the moment one alights or takes off, while it’s preening, or at the moment a favorable gust of wind exposes the legs. And the way a shrike survives year after year is to be wary and learn from mistakes—Ryan’s record-breaker quickly figured out his trap and stopped being catchable. But Ryan is a most tenacious and determined person, and like that saw-whet owl, he doesn’t miss a thing. When we located a pale-lored female shrike in the right territory, he kept his eyes trained on her every moment until he clearly saw her leg bands. What’s so important about knowing the ages of birds? Many people think of birds as they do of mice, as creatures with high reproductive rates and short life spans. That may be true of Zebra Finches in artificial situations, but it’s far from true of wild birds. Banded Black-capped Chickadees have lived over 12 years, and even tiny Ruby-throated Hummingbirds sporting bands have been retrapped, still alive, when a minimum of 9 years old.