Re-read what RyanT and Tursiops said: I'm also a marine biology professor and couldn't echo it any better. Take math. Lots of it. Take chemistry and physics (if possible) in high school. Major in Biology. Schools that offer "Marine Biology" undergraduate majors are doing it to attract freshmen, not graduate seniors with a degree that's substantially different from a Biology major. Look for schools that have marine labs and are members of the National Association of Marine Laboratories. Also keep in mind that for top students NSF and NOAA offer great, paid internships. (I'm skeptical about "volunteer" ones, though if they pay room and board, great! Some basically charge you to do work for them, and their are enough students who will take them up on it that it works.)
Lastly, don't rule out a maritime academy. If it's being on the water he loves, ship's officers spend a lot of time on the water. And I suspect the competition isn't as fierce as it is for folks who want to commune with whales. Despite teaching at a University, I'm convinced a lot of students would be better off in the long pursuing this kind of path, or being plumbers or electricians. In my neck of the woods, electricians and plumbers make more than most college professors....
That said, outside academics marine biologists work for state agencies, the feds, and environmental consulting firms. E.g., in Washington State you need a hydraulic project approval to build, say, a dock. That requires an underwater plant community survey. That, in turn, requires a diving marine biologist....
Lastly, don't rule out a maritime academy. If it's being on the water he loves, ship's officers spend a lot of time on the water. And I suspect the competition isn't as fierce as it is for folks who want to commune with whales. Despite teaching at a University, I'm convinced a lot of students would be better off in the long pursuing this kind of path, or being plumbers or electricians. In my neck of the woods, electricians and plumbers make more than most college professors....
That said, outside academics marine biologists work for state agencies, the feds, and environmental consulting firms. E.g., in Washington State you need a hydraulic project approval to build, say, a dock. That requires an underwater plant community survey. That, in turn, requires a diving marine biologist....