[DrDNA]

If marine biology is your passion then follow it. But, if you want a decent career in science, you should plan on, at minimum, getting a master's degree. There is no doubt you could earn a lot more money being an engineer, attorney (God help you..), accountant, etc. But, if you have a job that you truly enjoy and look forward to doing every day, you will have a better quality of life than just getting a fat paycheck doing a job you don't have a passion for.

I have a BSc in marine ecology and PhD in genetics. Very few people who get 4 year degrees in marine biology end up doing anything marine biology-related for a career. With just a BS degree, you'd probably be making around $40K-ish a year, depending what you were doing and where you were working. With an advanced degree, you could double that, though not initially. Even many university faculty positions in the biological sciences (excluding medicine of course) only start people in the $40-50K range, though they top out well over $100K after several years. But, you also are under the gun to write grants and bring in money to support "academic big business" and have to deal with a lot of unversity beaurocratic BS. It is not the ivory tower most people believe it to be, and is the reason I work for another part of government.

Anyway, you'll get a lot of differing opinions!