With an insect in its mouth, a yellow warbler takes off in Grand Teton National Park, Wyoming, in 2012.Warblers, which dine on midges, caterpillars, and leafhoppers, are recorded during the annual Audubon Christmas Bird Count. One of the longest and largest citizen science projects in the world, the bird count celebrates its 115th anniversary this winter.—By Christy Ullrich Barcus, photo gallery by Kathy Moran