Be careful with economic models to quantify the "value" of ecosystems. What is the value of a supercollider, or of the Hubble telescope? Neither one saved many lives; the money would have been better invested in diarrhea medicine for the third world if human benefits are the test. Or would Mr. Kareiva put a value on satisfying curiosity? How would he do that? Likewise investing in the kind of environment we want to live in: Sometimes the value of something is determined by nothing so much as the price that we as a society are willing to pay for it. We establish values by the choices we make. We can and should argue about those values, but the practice of quantifying them is fraught with trickery. It tends to be a way of giving pseudo scientific sanction to the values hidden in the numbers. Pushing the idea that the more humans benefit the better we're doing conservation is either a primary value masquerading as pragmatism or pragmatism posing as a primary value. I'll accept the latter. If saving the planet can only successfully be phrased in terms of human benefits, then that's the way we'd better phrase it. But there are pitfalls: how much benefit, how many people? If the long-term prospects of the species are a primary value, then rather drastically limiting near-term human benefits is probably an imperative. I suggest reading Gott, Nature 363:315 (1993).

Peter Kareiva has it right. There is absolutely nothing wrong with protecting nature for people. To hold fast to the notion that the Conservancy should be only about securing land from development is to ensure limited results for conservation. Kareiva's ideas are refreshingly forward thinking and have made me glad to have just renewed my membership in the Conservancy.

To me the most salient question, which TNC could clarify, is: to what extent is Mr. Kareiva one voice on "A Team of Rivals"; or is the TNCs current vision of conservation "less and less about protected areas and increasingly about working landscapes, in which the most intrusive human activities are planned for and managed to generate the least damage..."? Some of the letters in the summer edition seemed written by non-members, e.g. referring to "your legacy" (I guess I had been thinking of it as "our legacy"!). Might it be useful to differentiate between the views of members and non-members? Sincerely yours, Mary Koenen

TNC is welcome to hire whoever it wants as 'chief scientist', even if that 'scientist' is apparently afflicted with a primitive, pre-scientific, faith-based worldview. Likewise, I am free to specify any charitable organization I desire as beneficiary of my estate. Appropriate action is being taken - enough said.

I personally found Kareiva's view refreshing coming from a conservation organization. Even though, I am one of the one the few that believes nature should be protected because of its intrinsic value, I am not naive to think that that kind of belief will save nature by itself. When you live in an overpopulated world where more than half are in poverty, I don't think protecting nature is their top priority. Therefore you need to convince the majority of people on this planet that protecting nature benefits them. So I believe greater success comes from being a pragmatist and collaborating with the ranchers and the fishermen - this is their livelihood not a lesiurely experience it is too most environmentalists. Furthermore has anyone noticed how well climate change is doing being spread to the masses. Not very well: people still believe it is made up. Environmentalists need to wake up and realize that doom and gloom doesn't work and isn't changing people's minds. Kareiva is right- you need to make the material relatable to regular joes to create change in this world.

Ever since man decided to abandon a life as a hunter gatherer he lost his genuine connection to the environment. Somewhere along the line he decided that he had God given "dominion" over the earth. That was rapidly morphed into a carte blanche assault on all things natural because they all belonged to man and existed solely for his use. Despite the best efforts of organizations like the Conservancy, that mind set persists around the globe. Protecting what little remains of an unsullied natural world should be a top priority. The fact that human population grows larger every day and demands an ever greater share of nature's realm is reason enough to protect nature for its own sake and minimize the impact of outside forces.

Let us care for both people and nature. Set our sights to a century or two hence, and a more optimal level of human population and consumption, and more people-friendly and nature-friendly stewardship of the earth. Our minds and hearts should be bold enough to accomplish both.

One can argue the merits of Mr. Kareiva's perspective. What one can't argue, I believe, is its inconsistency with the mission statement of The Nature Conservancy. So I respectfully suggest either you change the mission statement or replace the chief scientist. Broadening the mission statement to include his "all about us" viewpoint is required for intellectual consistency if Mr. Kareiva is to remain in his prominent position with The Nature Conservancy. Thanks.

This article about Peter Kareiva came just in time to save my NC membership. I have felt ambivalent about NC for a long time, and Kareiva’s role is one of the reasons why I have maintained my membership despite my discomfort with some of NC’s projects. Kareiva’s was one of the first voices of reason, expressing reservations about “invasion biology” in an article in the NY Times nearly ten years ago, entitled “Aliens often fit in fine.” (If my memory serves me well.) I support NC because I believe it is worthwhile to save land that has not yet been developed. However, when NC gets involved in the “restoration” of urban land that has been radically changed, I am sometimes appalled by the destruction that accompanies these efforts. I recently read Miracle Under the Oaks about the prairie and oak savannah “restorations” in Chicago. This is a project that NC supported and the originator of that project (Steve Packard) became an NC employee. This project is the epitome of the destructive nature of urban “restorations.” The pre-settlement landscape was arbitrarily selected for replication, despite an understanding that native Americans had artificially maintained the prairie by starting frequent fires that prevented the natural succession of the grassland to shrubs and ultimately to forest. In other words, there was nothing “natural” about the prairie that existed when European settlers arrived. Untold thousands of trees have been destroyed, both native and non-native. Broadcast burns are frequently conducted to maintain this artificially created landscape. Herbicides are used to destroy non-native plants and trees. Animals are killed if they are perceived as competitors to preferred native animals or plants. In other words, the land, the air, and the water are being poisoned by people claiming to be environmentalists. I had just previously read that NC is destroying European honeybees in their “restorations.” http://roomfordebate.blogs.nytimes.com/2009/09/02/saving-bees-what-we-know-now/ As you probably know, European honeybees are responsible for pollinating one-third of our agricultural crops and, unlike the native bees, are capable of producing honey. And so, I had just concluded that it was time to pull the plug on my NC membership when I read this article about Kareiva. Now I will wait and watch to see if Kareiva can turn NC in a more positive direction to preserve and protect and to quit DESTROYING. Best of luck to Peter Kareiva and the Nature Conservancy.

The article on Peter Kareiva [Spring 2011] must either be intentionally provocative or only showing half the picture. Surely The Nature Conservancy supported by the donations of money, land and time by countless individuals cannot truly believe that all of them are moved only by their need for water, food, security and livelihood. Call it religion, art, what-have-you, but there is a need among humans for beauty, grandeur, mystery and spirituality that responds to nature. Many of us believe that preserving nature is important beyond simply what can nature do for us. Your very next article [The Recovery Artist] puts the lie to Kareiva’s hypothesis that diversity doesn’t matter. If it didn’t, then you would have let Santa Cruz Island proceed to the endgame, where the golden eagles had eaten all the foxes and departed, where the feral pigs reign in thickets of invasive shrubs. Santa Cruz Island would have provided just as much water and security and perhaps more food and livelihood (for those willing to take it) than will the restored island. But it would not have been as attractive or felt as right. As Dr Kareiva undoubtedly knows from economic models, it is the indirect costs such as quality-of-life that matter as much if not more so than the direct costs. Such costs and values are admittedly much harder to quantify than direct costs, but that is to reason to argue that they do not exist.