Polar bears in the Arctic need to have a fat layer providing great insulation. They must have a minimum of 10 centimetres of fat to survive the cold. It also provides buoyancy if the bear needs to swim. The layer of fat also provides energy storage when a meal is not around. This energy storage is especially critical for pregnant females that can go without eating for as long as eight months in some areas of the polar bear’s range. The wild diet of the polar bear is 90 to 95 percent fat to provide the fat layer. In captivity of the San Diego zoo, polar bears have a diet that is only 5 to 10 percent fat. This gives them the right amount nutritionally for the Californian climate but doesn’t give them the amount of fat to build a fat layer for warmth. And that is where all the carrots come in to play. The Zoo gives them as many carrots as they want all day. They really do like them! The bears are never hungry since any time they want a snack they eat their carrots. No real study has been done on the ability of polar bears to absorb calories from carrots.
From album: Californian Marine Reserves