This is an essay by Dave Foreman of the Rewilding Institute. It appeared in New West.
Foreman is correct, I think that some conservation groups have given into resourcism, with the Nature Conservancy being a prime example.
To quote Foreman, the principles of resourcism are:
1) Professionalism—Trained experts are best qualified to manage natural resources and public lands.
2) Progressivism/Optimism—Progress as a secular religion of material, informational, moral, and organizational advances is key to resourcism, as is an intensely optimistic view of the future benefits of wise management.
3) Engineering—The science behind resourcism is manipulative and controlling—not pure science, but rather technology and engineering.
4) Resources for people—Resource management by experts is to result in benefits for everyone. (In principle this standard is still touted; in practice it is corrupted in favor of those with wealth and political power.)
5) Multiple Use—Properly managed lands can produce multiple uses of timber, minerals, forage, water, wildlife, and recreation, often on the same acre.
6) Sustained Yield—Lands are to be managed for the maximum they can produce on a sustained basis without harming the future productivity of the land.
7) Utilitarianism—Resources and the land are here to be used to produce goods and services for humans.
A fair number of people who post here seem to take the principles above as given.