No,

that is some "logic", as we know it from children:

"if I close my eyes I can't see You, and You can't see me".

Because smell is the most important sense for a polar bear, he

translates that to:

"If I can't smell him, he can't smell me"

Hi Nicholas,

>When polar bears hunt, they crouch down by a hole in the ice and wait for a seal.<

I too have heard that story, but I don’t believe it. Such footage as I have seen of hunting polar bears showed no systematic covering of the nose with the paws. Anyway, they don’t wait for the seal to come out and look around (they would go pretty hungry if they did!) They generally grab it as soon as it surfaces.

So my answer is: I don’t believe they do know their noses are black.

Polar bears don't normally prey on animals that would require a stalking, so wouldn't usually have to hide in the snow in the first place. They normally prey off of dead carcasses, baby seals in ice caves or adult seals beside breathing holes. In any of these cases, hiding a conspicuous black nose would be unnecessary. It is a very popular myth, but seems to hold no merit. I doubt they would know if their noses are black, even though they are not colour blind. They may know, but it doesn't make a huge difference in their ability to hunt.