Are polar bears actually white in colour?  

Polar bears, those bear-like big furry animals from the North that you line up to check out in a zoo are white, right? Not quite. Actually, you may have noticed that they sometimes look even yellow, grey or green. But why is that so? Are there different species of polar bears with different colours? Do they keep changing their colour? Or do they also become what they eat like flamingos? No, none of that. Their colour is actually determined by the lighting and the surroundings since their fur is translucent and their skin is black.  

The science behind the colour  
When light strikes their fur, some of it is absorbed while the rest is scattered away. Normally, polar bears look white because their fur is scattering sunlight, which is also white.  

So when does a polar bear turn grey? In summers, polar bears produce thinner coats or fur and a little bit of their black skin undertone shows through the coat to appear grey. Similarly, more exposure to sunlight oxidises their hair strands, creating a yellowish appearance.  

You can also chance upon a greenish polar bear in a zoo in a warm climate area. The green is generally supposed to be a result of the algae infestation in their surroundings. 

Why have polar bears evolved to be white? 
Polar bears have a special set of adaptations that allow them to live in the cold Arctic region. The thick layer of their body fat and fur keeps them warm while swimming and insulates them from the cold Arctic air. 

Their white colour allows them to blend in as they roam across ice and snow in search of seals to eat. Now, that sounds right; can you imagine a brown bear trying to stay hidden from its prey in bright, white snow? A polar bear’s coat is so well-camouflaged in Arctic environments that it can sometimes pass as a snow drift.  

Bear facts  

• Polar bears live in the Arctic, on ice-covered waters. 
• Polar bear is the most carnivorous member of the bear family, feeding mainly on ringed seals.  
• Polar bears are very talented swimmers.  
• Polar bears like to keep clean because it helps the insulating properties of their fur. Fur that is dirty, matted, and wet does not work as well as an insulator.  
• The loss of sea ice habitat is the biggest threat to the survival of polar bears.