WINTER MIGRATION 2018

Jackie Duffin and Bob Wolfe, neighbours on the Aragon Road, sent us early morning photos of water birds congregating on a thin sheet of ice that had formed overnight on Colonel By Lake

“On 22 Nov we woke up to find the lake had frozen with the extreme early cold….(the only year it happened earlier was 1995). But more amazing was the massive number of geese and some ducks that had flown in the evening before and remained there overnight. At first we couldn’t tell it they were floating in the water or sitting on top of the ice. As it got brighter we learned that it was the latter. They were huddled to keep warm — and to our amazement a lonely swan showed up too. By the end of the day they had all flown away.”

The photo below is especially beautiful with some of the birds in focus while others are resting in the early morning fog that hovers over the cold surface. To the right of the standing geese seems to be a little open water with two geese floating in the opening.

Why don’t their feet freeze to the ice? I looked it up on Google: Ducks, as well as many other birds, have a counter-current heat exchange system between the arteries and veins in their legs. Warm arterial blood flowing to the feet passes close to cold venous blood returning from the feet.”

That means the arterial blood flowing into the feet has given off its heat-energy to the the venous blood that is being returned to the body. And that means the cooled arterial blood flowing into the feet doesn’t lose much heat to the cold ice.  In this way only five percent of body heat is lost through the feet. In fact the feet are close enough to the temperature of the ice that they don’t freeze to it. A wonderful evolutionary heat exchange system.

Why don’t  waterfowl  that float and swim in ice-cold water not become hypothermic and die? Are the feathers and down so well organised in layers that the skin doesn’t get wet? And therefore the body doesn’t lose much heat? After all we would die from hypothermia in less than a few minutes if we were submerged in water at zero degree Celsius.

Google: “If you can watch some ducks for a while you might notice that they spend a lot of time nibbling their feathers with their beaks. This is called preening. While the duck is preening she is spreading oil all over her top layer of feathers. The oil comes from a special place near her tail called a gland and when she spreads the oil over her feathers it makes her feathers waterproof. The water can’t get through the first layer of oily feathers and so all of her feathers underneath stay dry and fluffy and keep her warm all over.”

A view from the Wolfe/Duffin property on Colonel By Lake, just north of Kingston Mills on the Rideau Canal between Ottawa and Kingston, Ontario.

Among the many geese there is one lonely swan.

This could be a mute swan, a trumpeter, or a tundra swan. It is difficult to see from a distance like this. It’s most likely a mute swan, the ones we see each spring and summer on Colonel By Lake and in the River Styx. These swans are an introduced species from Europe and Asia. They have an orange coloured beak and an elegantly curved neck while swimming. Tundra and trumpeter swans have a black beak with a straight neck and are more in groups. We saw them last week on our visit to the Opinican Resort at Chaffeys Locks on Lake Opinican about forty kilometers north of Kingston on the Rideau Canal.

We hope you like the photos of a very late fall migration on our doorsteps.

 Click on the icon  of the mute swan to go to the INDEX of this site

 

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