question about water fowl

[grasswire]

So last night I took the dog out in near zero weather. We live on the banks of a big river. I noticed by the light of the moon that the Canada geese were IN the river. Usually sthey spend the night nestled in a bay. But great bunches of them were IN the river, talking to each other as if settled there for the cold night.

It seemed like such a cold thing to do. Is it because the water is obviously warmer than the air? The water must be about 40 degrees. Just some ice along the shore this morning.

But what fantastic kind of skin do they have on their legs and feet to not freeze in sub-zero weather?

[Tobin S.]

1. I've thought of this before, too.

It's amazing how those birds can tolerate frigid water. Sorry, I don't have any answers, though.

[TreasonousBastard]

2. Ever seen the gulls in the North Atlantic...

floating in the sounds between fishing trips and raiding the garbage dump? We have them all winter around here.

Waterfowl have a layer of special fat under the skin, similar to seals and other marine mammals, that reduces heat loss through the water and their skin, feet, eyes..., like other birds that survive northern winters, have evolved to deal with it. Feathers help, too

http://birding.about.com/od/birdingbasics/a/howbirdskeepwarm.htm

[Paulie]

3. Here ya go

http://askanaturalist.com/why-don%E2%80%99t-ducks%E2%80%99-feet-freeze/

The Short Answer: It’s all about heat exchange, and the smaller the temperature difference between two objects, the more slowly heat will be exchanged. 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. The arterial blood warms up the venous blood, dropping in temperature as it does so. This means that the blood that flows through the feet is relatively cool. This keeps the feet supplied with just enough blood to provide tissues with food and oxygen, and just warm enough to avoid frostbite. But by limiting the temperature difference between the feet and the ice, heat loss is greatly reduced.

[In_The_Wind]

4. cool link

[XemaSab]

5. Good answer

[grasswire]

9. thanks, very interesting

[MiddleFingerMom]

11. !!!

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[grasswire]

10. wish my feet were like that

Thanks for the link.

[B Calm]

12. That would be nice, LOL

I'd like the ability of flight too.

[RebelOne]

6. They felt safe there because there were no hunters around at that time. n/t

[grasswire]

8. good thought...

....but there are no hunters here. We're in an urban area.

Good thinking, though. Thanks.