Swan Numbers at Record Levels
Game and Fish asks the public to report observations
by Wyoming Game & Fish
November 21, 2007
Jackson - Trumpeter swans nesting in Wyoming shattered all records in 2007, delighting Wyoming Game and Fish Department (WGFD) biologists who have worked for years to increase numbers and distribution of swans in the state.
A total of 35 pairs occupied nest sites, 20 pairs hatched 74 young (called cygnets), and 59 cygnets (80%) survived until large enough to fly in late fall. This represents a 55% increase in number of nesting pairs and a 140% increase in productivity compared with the previous 10-year averages, according to Susan Patla, Wyoming Game and Fish Department Nongame Biologist in Jackson, who monitors the wild trumpeter swan population for the state.
"All the right factors came together this year," Patla explained. "We had an exceptionally warm spring, so wetlands opened up early allowing aquatic vegetation (the main source of food for swans) to develop quickly. Winter survival was good, and a number of new pairs, in the three- to five-year-old range, were ready to establish nesting territories."
The trumpeter swan is Wyoming's rarest native nesting waterfowl species. Year-round resident trumpeter swans in Wyoming are part of the tri-state population that nests in the Greater Yellowstone Area of Idaho, Montana and Wyoming. Major risks faced by tri-state swans include a low population number, low productivity, and very limited distribution in one of the harshest climates in the United States. They also must compete with over 4000 Canadian swans that spend the winter months in the Yellowstone area.
Patla, along with other biologists in the Greater Yellowstone Trumpeter Swan Working Group, coordinate surveys and meet every fall to compile data and develop management plans. This group formed after swan numbers hit a low in 1993, when only 278 swans were found in the Greater Yellowstone Area.
This year results were good with the total number of tri-state swans in the fall survey up to 498, the highest number since 1991. Results among the states were mixed, however. Swans in Montana did well with 41 young produced, but Idaho reported only 15 cygnets, much lower than average. Drought conditions affected water levels at many Idaho nest sites.
Wyoming's success in 2007 reflects not only good onditions but the success of the Game and Fish department*s swan expansion program. In the past, swans nested only in a small portion of the state in Yellowstone and Grand Teton National Parks and in the Jackson Hole area.
Between 1994 and 2004, WGFD released captive raised swans in the Green River Basin to increase both summer and winter distribution of the species.
Since swans are very traditional and follow their parent*s movement patterns, it is difficult to get them to expand into new areas. Over 70 young swans were released, and nesting pairs slowly became established at Seedskadee National Wildlife Refuge and north to the Pinedale area. Now a new generation of young swans from the released birds have began producing.
In 2007, there were 11 nesting pairs in the traditional core Jackson/Snake River area and 13 in the Green River drainage. A total of 31 young were produced in the core area and 28 in the expansion area. A pair also attempted to nest at the Alpine wetland in the Salt River drainage.
The WGFD swan program has now shifted gears and is concentrating on working with landowners and other partners to build and restore new wetlands to provide high quality summer habitat for nesting swans and other waterfowl and wetland species. Funding was obtained in 2007 for two projects in the Pinedale and Daniel area through the NRCS Wetland Reserve Program, Wyoming Wildlife and Natural Resource Trust, and the Wyoming Landscape Conservation Initiative.
The public can become involved in swan conservation in a number of ways. First of all, WGFD requests that observers report any collared or marked swans to their local WGFD office. Reports should include date, location, number of swans, and type and color of marker. Swans are marked with different colored neck bands that have distinct codes, or leg bands. The department will follow up and provide information on the history of any marked swans reported.
Second, everyone should take care not to disturb swans in summer or winter. If swans begin to move away or call when you approach, back off. Causing swans to fly away from feeding or resting areas results in loss of valuable calories and can make the difference between life and death. Each winter a number of swans die of starvation; cygnets are especially vulnerable given their low body weight.
Third, please report observations of swans hitting wires, fences or bridges. WGFD works with power companies and landowners to mark obstacles where swans and other bird collisions may occur. Collisions are one of the highest causes of mortalities for swans, the largest waterfowl in North America. It is difficult for swans to avoid obstacles, especially in low light conditions or when flushed suddenly off a wetland.
Lastly, consider developing or enhancing a wetland for swans if you have adequate space and water. WGFD has developed guidelines that explain what features swans need for summer habitat. To request the swan habitat guidelines or report swan observations you may contact: Wyoming Game and Fish Department Nongame Biologist, Susan Patla at 1-800-423-4113 or 307-733-2321, or email at Susan.Patla@wgf.state.wy.us.