Trumpeter Swan sightings wanted
by Wyoming Game & Fish
November 20, 2004
The Wyoming Game and Fish Department would like to hear from everyone seeing a trumpeter swan - North American’s largest waterfowl -- marked with a neck collar or colored leg band. Report the color of the collar or band, and coding if possible, along with location and date to the nearest G&F office or to Susan Patla, nongame biologist at the Jackson Office, (800) 423-4113. She says the tracking information helps biologists determine migration patterns and how long swans live.
Early November offers the best opportunity for Wyoming residents to see trumpeter swans. Thousands of trumpeters migrate south from interior Canada to winter in the Greater Yellowstone Area. Between 300 and 600 will winter in western Wyoming along with approximately 100 swans that live year around in the area.
Often intermixed with trumpeter flocks will be some tundra swans. This slightly smaller species nests far north in arctic wetlands and most will continue to pass through the state to winter farther south in Utah, Nevada or California.
Both species require secure, shallow water wetlands for foraging as their main food source is submerged aquatic plants. Trumpeter swans often congregate in large groups at staging sites such as Jackson Lake, the National Elk Refuge, Alpine wetlands or Fontenelle Reservoir before scattering to rivers or smaller isolated ponds and creeks that stay open year round. Swans learn from their parents and tend to return to the same areas year after year if undisturbed. Family groups have dominance over pairs or singles, and occupy the highest quality habitats.
The bird’s vocalizations can be the easiest way to distinguish the different species. Tundra swans have a much higher pitched call compared to the deep-voiced trumpeter. Adult tundra swans usually have a distinct yellow mark on the bill just below the eye. The young of the year, or cygnets, of both species will be gray, but trumpeter young have pinkish legs and feet compared to dark black of tundra cygnets. From a distance, it can be impossible to determine species even for experienced bird watchers.
The population of resident trumpeter swans in the Greater Yellowstone or tri-state area of Wyoming, Idaho and Montana now number less than 300, which is fewer than the late 1980s. Canada swans have increased greatly over the past 20 years. The decline of the tri-state flock seems to be the result of a number of interacting factors including continuing drought, competition with Canada swans for winter habitat, cessation of winter feeding at Red Rock Lake National Wildlife Refuge in Montana and growing human population and related habitat loss and disturbance. High winter mortality can result if swans cannot get adequate nutrition. Each year swans perish from starvation, disease, collisions with power lines and fences, and predation.
Wildlife managers hope to increase numbers of resident trumpeter swans by increasing distribution in both summer and winter. Over the past twenty years, WGFD has translocated captive-reared swans into the Salt and Green River drainages. In 2004, for the first time, an equal number of pairs (11) occupied nest sites in the Green River expansion area as in the traditional core nesting area around Jackson. Swans hatched 54 cygnets in 2004, a record number, with 30 produced in the Green River basin. Over all, 68 percent of the cygnets survived until fall when they could fly and move to wintering grounds with their parents.
Due to the success of G&F’s expansion program, the department no longer plans to release captive swans in the Green River area and has shifted efforts to habitat development. In 2004, the G&F obtained funds from the federal State Wildlife Grant Program to survey potential nesting habitat in the Green River Basin. Surveys were conducted at over 30 locations and site plans are being developed for 22 new wetland projects. The G&F will seek additional funding to create new swan wetlands over the next few years, which will also benefit many other species.
Patla encourages everyone to enjoy swan watching but also cautions observers not to disturb swans and flush them away from needed feeding and resting sites. If swans start to "head-bob" and vocalize, it is best to draw back before they are forced to fly. Controlling dogs at swan wintering sites is also important. If swans lose their sense of security at a particular site, they may not return even if food resources are limited elsewhere.
One of the best places to see, hear and photograph swans close-up is at the Flat Creek Overlook on the National Elk Refuge just north of Jackson. Numbers will peak here by mid-November and drop-off as the marsh freezes.
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