Tundra vs. Trumpeter Swan

[Gord]

The two species are often fairly easy to ID when at close range, and usually picked out by their calls.

A trumpeter swan's call is a deep honking while a tundra swan's call is a more of a higher pitched hooting "woo! woo! woo!" Tundra swans used to be called 'whistling swans'; probably based on their call as described. Once you've heard both, they're pretty obvious.

But often the two species will mix together. You may hear tundra swans among a large flock of swans, but be unsure of exactly how many of each there actually is never mind being able to point at one and say which it is.

Tundra swans are smaller than trumpeter and to me, often whiter. Bills and necks are a bit shorter. They're also more 'curvy' lacking the fairly straight forehead and bill, and a more rounded back.

One fairly reliable fieldmark is the yellow spot on the base of most tundra swans bills near the eye. Some do not have it and those who do, it varies from very small to rather large. It is not often easy to spot this mark, especially on individuals who have the smallest spot. There are also small differences in how the bill meets the head of each. Ill post a picture of a family of tundra swans taken at Eagle Point recently. It's a good picture in the way that it shows the extremes in the yellow spot sizes and has a juvenile as well. (tundra juveniles have pale bills right to the base while trumpeter swans have dark based bills with less pale). I will dig up some of trumpeter swans shots as well when I track them down and then expand on what I know of these guys in more detail.

[Gord]

The promised image of a trumpeter swan. Note how the bill attaches to the head. It comes from more of a straight angle from the eye than seen in the tundra swan.

[Gord]

Some more tundra and trumpeter swans for comparison.

This is about as much a tundra swan gets for yellow...(note the juvenile tundra swan's tail to the right)





This is the small end of average.




And here's a trumpeter swan.




Remember, some tundra swans (few in my experience) have no visible yellow so structure of the bird's body, head/bill shape, call and sometimes plumage (juv tundra swans go white sooner than trumpeter) are good to keep in mind.

Some of the above can be seen even in the reduced image. With practice, you can tell the two apart from a distance.







Close-up of a juv tundra.