In the 1960s, a Paradise Valley landowner acquired 2 mute swans for their beauty; by the late 1970s, they numbered 120, prompting a Yellowstone-led removal effort in 1987

In Montana's Paradise Valley, the introduction of non-native mute swans, intended to enhance the scenic beauty, led to an unexpected explosion in their population. These assertive birds posed a serious threat to the local trumpeter swans in Yellowstone National Park. Starting in 1987, a dedicated conservation program aimed to eliminate mute swans and restore the trumpeter population, ultimately succeeding by the mid-1990s.