During one of our trips to northwestern Oklahoma I noticed hundreds of strange looking nests on the underside of the bridges. When I got home, I did a bit of research and I discovered that they belonged to the cliff swallow. I had never seen such a nest before, and they are indeed strange looking. They are made mostly of mud and tend to sit at a 90 degree angle under many of the state’s bridges.
According to the Cornell School of Ornithology, “Busy flocks of Cliff Swallows often swarm around bridges and overpasses in summer, offering passers-by a chance to admire avian architecture and family life at once. Clusters of their intricate mud nests cling to vertical walls, and when a Cliff Swallow is home you can see its bright forehead glowing from the dim entrance”.
Photo source US Forest Service
According to Oklahoma Birds and Butterflies.com, the cliff swallows live in Oklahoma during the summer, while the rest of the year they live in South America. They live in colonies with nests made from mud pellets that are usually located under bridges or the eaves of buildings. The colonies which my family and I saw numbered several hundred birds. It was quite a sight!