My final week on Hokkaido I ventured north to the Shiretoko Peninsula. Here is a last vestige of wildness in Japan, as close to an "end of the earth" experience as you're likely to find in this highly populated nation. Here are mountains still covered by old growth forests, with tumbling streams and pristine lakes. It all ends in a dramatic coastline of black basalt and sparkling waterfalls.

The tip of the peninsula is a national park and refuge for some critters not normally associated with Japan, including a rare brown bear or two. It is also a holdout for one of the world's largest and most stunning raptors, the Steller's sea eagle.

Eastern Hokkaido is also a good place to witness the sometimes paradoxical effects of wildlife protection. Sharing the forests of Shiretoko with the elusive bears are thousands of Sika deer, a small creature with large eyes and a haunting whistle. The deer have overrun much of Japan, the result of a ban on hunting in 1888 and a lack of natural predators. With this population surge has come forest defoliation and crop damage. This scenario has a parallel in the United States with white tail deer and in Australia with rabbits. And there are many others worldwide that tell the same tale.

In this enlightened era of conservation man wants to control wildlife populations and prevent extinctions. The goal is to maintain adequate numbers for genetic diversity but not so many as to become a human pest. This "volume" adjustment can be difficult to achieve in nature, as we've seen so often in the past when we tamper with the balance of nature. Our best efforts go awry and lead to ethical questions.

How does a crane's need for open wetland jive with our need for rice. When do we deny ourselves the pleasure of interaction with a species and would we still protect it if we never saw it? There are many others. Environmental science and conservation biology attempt to answer these difficult questions.