Life through my lens: Canada's spirit bear I had been waiting quietly on the riverbank for several hours, listening to the gentle patter of rain. Every so often a black bear would pass by, fishing for salmon on its way upstream. But suddenly an apparition emerged, ghostlike, from the dark recesses of the forest: a rare and elusive spirit bear. I was in Canada's Great Bear Rainforest, the largest remaining tract of intact temperate rainforest left in the world, which stretches seamlessly from the northern end of Vancouver Island all the way to south-east Alaska. This breathtaking wilderness is chock-full of wildlife, but the spirit bear is the jewel in its crown. One of the animal world's great enigmas, it is a walking contradiction - a white black bear (an extremely rare colour variant of the American black bear). It is neither a polar bear nor albino. It has normal pigmentation in its eyes, nose and skin and the whiteness comes from a recessive gene, so, to be born white, the bear must inherit the gene from both parents. Also known as the ghost bear, or Kermode bear (named after Francis Kermode, former director of the Royal British Columbia Museum), it is elusive and rarely seen - except for a few weeks every year in one tiny corner of the forest. Found nowhere else in the world, it spends the winter fast asleep and prefers to hide in the dark, tangled recesses of the forest. But if you go to the right place, at the right time of year, your chances of a close encounter are surprisingly good. On this occasion, I crept down to the water's edge and waded out into the river to get a clearer shot. The bear considered me for a moment, before turning its attention back to the water to fish. We spent nearly an hour together, sometimes almost within touching distance, before my new-found friend had eaten his fill and disappeared back into the forest. Telegraph readers can buy a signed copy of Mark's Carwadine's new book, Mark Carwardine's Ultimate Wildlife Experiences, ahead of publication in the spring, at a specially reduced price of £15 (down from £25) plus £3 p & p. After more than 30 years travelling the world in search of wildlife, Mark has outlined the best places to go, when to go, how to do it and what to expect. To buy the book, visit markcarwardine.com.