Thanks for your question. There are many different career paths with a marine biology degree. My recommendation would be if you have a public aquarium near you, go visit and talk to the employees to find out the different jobs and backgrounds. Here are few examples.
Aquarist-work directly with the animals under your care in a public aquarium setting. This can include sharks, rays, sea turtles, fish, invertebrates, and corals.
Marine Mammal Specialist-work directly with any mammals that might be in a public setting, which could include dolphins, seals, otters, whales or any other air breathing animal.
Animal Rescue and Rehabilitation- these jobs work with rescuing. injured sea animals or sea birds, assisting with medical care and reintroduction into the wild.
Conservation Education-work directly with the public educating about marine species and conservation.
Research-This is usually very specific to a species and often requires that you have an advanced degree beyond your bachelors degree in college.
I learned in college that I really had a passion for Sea Turtles, so I focused my work on that species. I spend the summer at the beach's monitoring Sea Turtle nests. It is great work, and I have a great opportunity to interact with the public to educate them about sea turtle and how they can help protect them and all the hatchlings. Once you are in college, you can work with different professors that might be doing some field work to find your passion! :) I would also recommend to get SCUBA certified if you are not already. A lot of our work sometimes requires that we are underwater. Hope that helps a bit. Feel free to send any other questions.
I am not a practicing marine biologist but I have worked with them and have some insight on the career perils and pleasures. First, it seems you must know something about marine biology if you wish to become one. But to polish the picture a bit, I would first summarize how you would become a marine biologist. You certainly must go to higher education for maybe a BS degree and you may do well to get that degree in an institution that has a marine sciences program or at least a one or more accomplished marine biologist professors. They may suggest you continue to graduate school for an MS or certainly a Ph D. Those details work themselves out as you go!
You will likely find there are many types of marine biology careers. On one hand you may go into government to work with an agency such as NOAA, NSF, or maybe even the EPA. Or you might select a research interest on your own and you may go into a University faculty position. Remember that last option can be nearly anywhere. I knew a marine biologist at Ohio University who specialized in “interstitial meiofauna.” which means his specialty was studying little things that crawl around in sand. He went to Scotland for a month every year and came back with a trunk load of preserved sand samples which kept him busy for the rest of the year.
On the other hand you may be interested in macrofauna and flora. That would be either a government program or maybe industry. I knew a marine biologist who spent several years on a factory fishing ship off the coast of Alaska. She monitored the number, size and identity of the species of fish they caught and plotted the data to follow the general health of the local fish populations. But after a while she had had enough of that and moved on to other activities.
Other fishery interests deal with disease in fish. Substantial die-offs may occur in certain areas and often there is no known reason why. The Florida Bay was literally dying off. Both fish and plant life were disappearing. So marine biologists with the Fish and Game Commission as well as state EPA had to study it very closely to find out why. Ultimately it had a lot to do with poorly treated sewage and overgrowth of toxic algae. So what do you do about it, how long will it take, and how are you going to monitor the effectiveness of remediation measures? All questions for marine biologists.
I have worked with the Delaware River Basin Commission which continually monitors the fisheries and general wildlife of the Delaware River Basin. Some of the biologists are typical ecologists as described above, but we also have marine toxicologists, measuring the toxicity of water and influents of the river. More down my line of work, some are continually sampling the water and sediment to be tested for poisons and bacteria.
I hope you can see there is a wide range of programs you can become a part of with marine biology. But you do need to be flexible, determined, thorough and dedicated.