Posted by: Karen Stevenson, Woodland Park Zoo Volunteer; additional contributions by Gretchen Albrecht, Zookeeper and Anna Martin, WPZ Volunteer Photo by Gretchen Albrecht/WPZ. Just a few weeks back, the memo came through. It read only, “They’re back!” “They” are barn swallows, Hirundo rustica , and we’re celebrating their return. Here in the Pacific Northwest, barn swallows are harbingers of spring’s longer, warmer days. Warmer days awaken long-dormant insects, and barn swallows—like most little insectivores—follow their food (mostly flies and mosquitos, but also beetles, bees, wasps and so on). They summer here, then when “summer” moves south, they do too, following available food all the way to northeastern South America and the Caribbean basin. Barn swallows are comfortable in our big cities, small towns, neighborhoods and farms. While other swallow species prefer to nest in natural structures hidden from view, such as cliffs or tree cavities, barn swallows build mud nes