Oceanography graduates typically earn around $73,500 per year, though people in different specialties receive widely different salaries. Some students use their general science knowledge to pursue other careers, while many oceanographers enter the profession with a different undergraduate major.
Unfortunately, finding employment without a postgraduate degree is fairly difficult. In a small world like oceanic research, it's rarely a bad idea to make as many friends and gain as much experience as you can.
Some avenues open to oceanographers include marine biology, fisheries consulting, aquatic chemistry, ocean geology, and ecological research. In many positions, they are expected to spend weeks to months on ships on occasion, sometimes in less than comfortable conditions.