Ravens know exactly what they’re doing.

Like their magpie and crow cousins, pretty much everything they do seems to have a purpose. Whether it’s gathering food or running off rivals or just having fun, ravens seem to do it all with diligence and thought.

I’d spent a couple afternoons over the past week looking for winter birds. Not for any birds in particular, just the usual sparrows, pigeons, ducks and geese that spend the winter here. There are always lots of them around. But though I know they seem to manage just fine with the cold and snow, I always wonder how they do it.

One way, of course, is to hang out where they know it’s warm. And one of the best places is anywhere there is flowing water.

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A little explanation? Sure, why not.

It’s actually pretty simple. As I’m sure you know, water freezes at 0 C — or 32 F if you’re olde skool — and frozen water doesn’t flow. Therefore, the temperature of flowing water must be at or above 0 C. The air around it could be much colder even a hand-width above the flow but right next to the water it is fairly warm.

And where the air is warm, life thrives. So I headed for the Bow River to have a look.

Unfortunately, I could barely see anything through all the fog.

You often see mist on a river even in the middle of summer but what was happening here was a combination of the relatively warm air right above the river mixing with the cold air higher up and making fog out of all the moisture in the entire air column. So not only was it misty along the river, the entire countryside along the Bow east of the city was wrapped in a dull grey haze.

The birds, though, were unfazed by it. Though they were hard to see, the river was thronged with mallards and mergansers, goldeneyes and geese. In places where I could get close enough, I watched them splash in the water as they dodged the mini icebergs and dove or dipped for food. I could hear them flying by, too, the whistling wings of the goldeneyes and the incessant honking of the geese.

And the........

© Calgary Herald