A marine biologist is usually a person with advanced degrees in life sciences. He or she will study life forms of the ocean from a scientific perspective, and may hold specific bachelors, masters, or PhDs in biology, marine biology, and/or chemistry.
There are many different areas in which marine biologists may work. They may help to protect life forms in a part of an ocean, or study the interactions of life forms in a specific ocean environment. They might also analyze the behaviors of fish species. Some specifically examine microscopic life forms or one species of fish only.
Some marine biologists work in aquariums to help keep fish populations healthy and comfortable in a confined space. They may care for injured large fish and run a relocation program. They also may supervise or participate in developing educational materials for visitors to an aquarium. In the field, observations help them learn how to care for fish of different species and also what material is vital for others to know.
Since frequently a marine biologist works in the field or more accurately, the ocean, most have to be adept swimmers and divers. This means in addition to college education, someone in this career usually holds a certificate in scuba diving.
However, not every marine biologist works near or in the ocean. Some work in landlocked areas analyzing research or teaching marine biology. However, it is difficult to get these positions unless one has participated in some practical research along the way. Thus being a good swimmer is an important requirement.
Many with advanced degrees work as professors, and also continue to conduct field studies. This means a marine biologist should be very adept at applying for science grants in order to conduct work or research. He or she should be a good writer, because many who work independently rely on grants as their sole form of payment.