Written by Gary Ivey
Due to the pressures of hunters and fur trappers, who targeted Trumpeter Swans, the species was near extinct at the turn of the 20th Century. A survey in 1932 found a mere 69 trumpeters alive in the United States. At the time the swans persisted in Montana’s Centennial Valley and Yellowstone National Park where severe winters kept out hunters and geothermal springs maintained enough open waters for a small group to survive.
Malheur Refuge was among the first of several sites selected for saving the Trumpeter Swan from extinction in the late 1930s. Malheur’s trumpeter flock began breeding in the 1950s and grew to a peak of 55 adults by 1983. The historic flood of the early 1980s allowed carp populations to decimate aquatic foods in Malheur Lake for 8 years and this loss of their traditional wintering site caused the flock to re-locate its wintering grounds to the south Blitzen Valley where much less food was available to sustain a large flock during severe winters. Consequently, because trumpeters imprint on their wintering sites, the flock has declined, mostly due to winter mortality caused by the very limited winter carrying-capacity. Malheur Refuge has supported only one breeding pair during the past 6 years and was down to only four adults (3 female and 1 male) in spring of 2020.
You may be familiar with the pair that had nesting consistent, yet largely unproductively, for the last 6 years at Benson Pond. The male uncollared and his mate who is uncollared is known as Theta 64. In the summer of 2020, the breeding male disappeared from his Benson Pond territory, leaving only the three females remaining at Malheur. Additionally, one of these females (Theta 76) went missing in September, which suggests the Refuge flock may be doomed to extinction.
Since 1992, Malheur Refuge staff have been involved in a project to expand the breeding and wintering range of trumpeters in Oregon through releases at Summer Lake Wildlife Area. Several new breeding pairs of trumpeters have been established from those releases and to date, about 20 wild-hatched trumpeters are in the Summer Lake flock. A young male from a pair which produced a brood along the Crooked River in Crook County in 2016 has found our missing female as identified by her color Theta 76. They have been observed together acting as a pair and wintering at Summer Lake Wildlife Area this fall. Our great hope is that she brings her new friend to Malheur and raise young that the pair can teach to winter at Summer Lake, where trumpeter habitat is not limiting the population. Cross your fingers!