Eight trumpeter swan cygnets recently were released in the Hayden Valley of Yellowstone National Park/NPS

Though trumpeter swans have never been listed as threatened or endangered under the Endangered Species Act, there long have been concerns about their population numbers. In a bid to boost those numbers in Yellowstone National Park, eight young trumpeter swans were recently set free at Alum Creek in the Hayden Valley.

On September 19 staff from the park, the Wyoming Wetlands Society, and Ricketts Conservation Foundation released the cygnets as part of an ongoing restoration project to increase territorial pairs of swans that have undergone a decades-long decline in the park. From a high of over 60 birds and 17 territorial pairs in the early 1960s, to only four birds in 2009 and 2010, the park's swan population has declined for a variety of reasons. Researchers are collecting population data such as nest success, number of territorial pairs, and the number of cygnets produced each year. This data may help determine the reasons for the decline.

Recent releases and other restoration efforts have bolstered the population to more than 20 birds and five territorial pairs, including natural reproduction in some years.

The effort is a public/private partnership between the National Park Service, Wyoming Wetlands Society, Ricketts Conservation Foundation, and Montana State University. Joe Ricketts, founder of Ricketts Conservation Foundation, participated in the recent cygnet release. His fund also supports other avian conservation efforts in the region, including common loons and Clark’s nutcrackers.