What degree is necessary for a career in conservation? I'm currently in school studying towards an A.S. in Natural Science. I'd like to have a focus on marine life, which leads me to believe I should get a B.S./B.A. in Marine Biology, however I want to be able to work in other areas well; such as aquatic life, land mammals, botany, forestry, &amp;c. My question is, what degree should I work towards to be able to work fluidly between conservation efforts. I'm rather lost in all the different degrees out there, I don't know which to pursue. The school I'm considering offers degrees in Marine Biology, Natural Science, Environmental Science, Agriculture and Management, Plant and Soil Science, Wildlife Management.

I'm also going to pursue a Master's after my Bachelo'rs. I was curious if it might be a good idea to get a Bachelor's in Marine Biology, then maybe a Master's in something much broader in order to expand my horizon so to speak. Or is it a better idea to just stick with one area and focus there?
The conservation, applied ecology, and natural resource management fields can be a tough job market depending upon your geographically location and what subfield you want to work in.  

For your undergraduate degree, any of the majors you listed would be reasonable. I would browse graduate programs you are remotely interested in and see what courses they require for admission. Some programs might requires 2-3 semester of calculus where others require none. Likewise, chemistry (e.g., organic) and physics requirements sometimes vary. As noted in a comment, your exact undergraduate degree does not matter if you plan on going to graduate school. However, some agencies (e.g., the US Federal government) have course requirements for jobs (e.g., a fish biologist). 

Academically, I suggest a double major or a minor in another field to give you technical skills to help you stand out. Possible examples might be chemistry, math or statistics, or something related to GIS.  

Outside of school, try to get as much experience as possible. Hopefully you can get payed summer job/internships. One great place to find these opportunities is the Texas A&amp;M Wildlife/Applied Ecology jobs board.  

The source for my information is my own experience. I am PhD-level research scientist working for a US natural resource research agency.