Date: 3/7/17 10:40 am From: Lars Per Norgren <larspernorgren...> Subject: [obol] Trumpeter Swans in the Willamette Basin
Evan Centani's Observation of Swans at Ankeny got me to wondering. There have been Trumpeter Swans in the vicinity of Airlie every winter since the mid-seventies. Ankeny NWR is very nearby, yet I'm not sure I've ever read a report of Trumpeters from there. It seems like small numbers of Trumpeters are now being reported from Finley, more than two but less than half a dozen, suggesting a single family. The large flock of Tundra Swans at Harrisburg has been wintering there since at least the early 70s, yet I've never read of a Trumpeter among them.
Maybe some of this is an artifact of observer effort and opportunity. The swans at both Airlie and Finley can on occasion be observed at very close range. When hundreds of swans are visible a mile away at Sauvie Island, there is little incentive to give them close scrutiny. A family sized group of Trumpeter Swans has been reported off and on in the general vicinity of Forest Grove for decades, and I believe folks have seen them around the former Trojan nuclear power plant, a place that is seldom mentioned on Obol. I'm struck by the stability of these small numbers. Over the decades the Trumpeters have neither gone up in numbers, nor disappeared.