I think the greatest challenge in environmentalism and the most rewarding challenge is trying to figure out how humans can meet their needs while protecting the environment.

We do have serious energy needs for the country, we are aware that natural gas is especially in demand because of its air quality benefits: 90 percent of new power plants have been natural gas-powered.

We also know that China and India, as their economies ramp up, are using more and more energy.

Dating back to Teddy Roosevelt, hunters have been the pillar of conservation in America, doing more than anyone to conserve wildlife and its habitat.

Predators make it much more difficult to find consensus. It's a lot easier to agree about birds and plants than about animals that endanger people and livestock.

In Washington, there's always an effort to label people.

I spend a year at the Hoover Institute at Stanford, researching market approaches to air pollution control.