In the US, you can do a thesis project on a specific topic of your choice, but I’ve found that the programs have fairly rigid standards and there’s not a lot of room to take elective classes. I’m not sure how programs work where you’re looking, though. I would try to get a job with the education you have and see how you like it, and only then decide if you want to go back for more school. This will let you find out if you would rather do urban or conservation studies.
