You can find seven different species of swallows nesting in Iowa. These are the bank, cliff, cave, purple martin, tree, northern rough-winged and barn. The purple martin is the largest swallow in North America.
Swallows have a variety of different nest types. This includes burrows, mud nests, and nesting boxes. Depending on the species swallows can have anywhere from 1 to 7 eggs in a brood and 1 or 2 broods a year.
Top photo: Yellowstone National Park
Bottom photo: Alan Schmierer