706 reactions · 199 shares | The United States' bison population diminished dramatically in the late 19th century. Follow their sparse sightings in Iowa at the time and learn more about two men with connections to our state, William Hornaday and John Lacy, and their roles in keeping the animal from vanishing altogether. | Iowa PBS | Facebook

376K views · 12K reactions | Sound on to hear bison bellows!  Mating season is in full swing at Neal Smith National Wildlife Refuge in Iowa. Bison bulls compete for a chance to mate, making deep vocalizations that echo across the prairie.  Nancy Corona/USFWS | U.S. Fish and Wildlife Service | Facebook