noun. One that practices or advocates conservation, especially of natural resources.

noun. A person who maintains natural areas or protects threatened species.

noun. Someone who advocates for these actions.

noun. someone who works to protect the environment from destruction or pollution

""I use the term conservationist when asked to describe myself, but to the extent that I'm an environmentalist, I do it out of a sense that it's the only sensible thing to do," Gibson said."

environmentalist  

crusader  meliorist  reformer  reformist  social reformer  

Carson  barbara ward  baroness jackson of lodsworth  green  rachel carson  

collaborationist  preservationist  reservationist  segregationist  

abstainer  biochemist  churchgoer  churchwoman  claustrophobe  

Audubon Society  National Wildlife Service  Sierra Club  arboriculturist  conservatist