Elk and Tourism, is it profitable to keep them around?

I love Yellowstone National Park, so naturally after Mr. Kay finished with his lecture I was disturbed. He was very persuasive, and after class I found myself thinking that Yellowstone had some serious issues to work out. I found an article that was expressing concern with some economic factors. It mentions how although tourism of Yellowstone has increased, prices have not, which means they do not have money (of course no one ever does) to continue its resource preservation. It also suggests that the elk are an importance source of revenue for the park because over 93% of tourists are there to see the elk. Would decreasing the amount of elk hurt the park financially? And if it did, would the increase in benefits to the ecosystem be enough of a justification for ridding Yellowstone of the elk population? I tend to think Yellowstone has enough other attractions to make the loss of ‘elk profit’ up just fine. Still, it’s clear to me that Yellowstone is in desperate need of some economists.