The World's Largest Swans

Once again, trumpeter swans have returned to Union Bay. 

A week ago I counted a total of fourteen swans. Seven had the pure white feathers of adults, and seven had the gray-brown coloring of juveniles. This was the first time I remember seeing an odd number of adults. During their regular winter visits, the adults usually arrive in pairs.

They can be spotted from shore, however they appear rather small in the distance. Be sure to bring binoculars or a scope. From Foster Island or the Waterfront Activities Center look to the northeast. From the eastern shore of the Union Bay Natural Area they are usually situated more directly to the east.

Swans often sleep during the day. With their heads down they look a lot like pillows laying on our low-lying, muddy-black islands. I would not be surprised if swans provided the inspiration for the first down-filled pillows. Those fluffy white feathers sure look soft and comfortable.

It is easy to imagine how a demure and elegant swan inspired Tchaikovsky's Swan Lake ballet. 

Their necks make the most mundane tasks,...

...appear refined and elegant.

Even the necks of juvenile swans hint at their future elegance. 

In this case, I believe the swan was simply waking up and stretching...

...however with a wingspan larger than that of a bald eagle...

...trumpeter swans are very impressive. The U. S. Fish and Wildlife says, "They are the largest waterfowl in North America and the largest swan in the world." They also credit the trumpeter with an eight foot wingspan. Not all sources agree, some state around six and a half feet, however I have also seen as much as a ten foot wingspan mentioned. I suspect that must be an exception, while six and a half feet is most likely the average.

On Monday, I watched a bald eagle swoop low over five resting trumpeter swans.  As the eagle descended - to pluck a fish from the water - the swans showed no signs of concern. They never even raised their heads. On average, the trumpeters are about twice the weight of a bald eagle, plus their wings are longer, stronger and heavier. I suspect their weight and wings are the primary source of their confidence. 

The five swans appeared to be a single family of two adults and three juveniles.

I spent most of the daylight hours simply watching them sleep. I was surprised to notice they did not feed at all. Since then, I have learned (please see the citation below) that they can feed at night as well as during the day. Maybe they prefer to sleep when it is warmer and to be active during the colder nights.

It is interesting to see the difference between this swan's primary and secondary feathers. The primaries are the swans longest wing feathers and, given their wing tip location and size, they are critically important feathers for flight. At this angle, the primaries have a watery blue tinge while most of the secondaries and coverts reflect a bright white light.

It is also interesting to see how white the underside of the juvenile wings are - especially when compared to their other feathers.

 I wonder if the ruffled look of the leading wing feathers has to do with new feathers still growing into place. 

Overall, I suspect a swan's neck is their most under-appreciated appendage. It is obvious that their necks allow them to harvest underwater food that is out of reach for ducks and geese, but it provides other benefits as well.

I think a swan's neck is actually most similar to human arm, given the variety of ways it is utilized.

 They can reach any and all areas of the body...

  ...for grooming... 

...and maintenance. 

The neck allows them to lift a mouthful of water, like we might lift a glass to our lips before swallowing the liquid.

The neck is also used in defense. When another swan gets too close, the irritated swan while strike out with the beak. If you watch you can see the head and neck coil back in preparation. The result is usually just a nip at the backside, but the offending swan moves briskly away, as if it has previously experienced pain in a similar situation. No doubt the strength of the neck adds a little extra bite to the strike.

Have you ever thought about the term, "Armed and dangerous." Why do we call someone who is carrying a weapon, "armed." Most people without weapons still have arms. I suspect the reason is because before firearms, the power of an assault came from the strength of the arm. A club or a rock intensified the damage, but it was the arm that made the attack possible. While wings on a swan may have originated from a similar source as our arms, I think it is their necks that have evolved to provide similar functionality.

 In case you did not notice it earlier...

 ...I wanted to point out the white eyelid on the juvenile, which closes to cover and protect the eye. In any case, beware of getting too close to the swans, not only does it disturb them and waste their energy but they are also...armed and dangerous.

Have a great day on Union Bay - where nature lives in the city!

Larry

Citation

Mitchell, Carl D. and Michael W. Eichholz. 2010. Trumpeter Swan (Cygnus buccinator), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/105

doi:10.2173/bna.105