The ocean is one of the Earth’s most incredible resources and it’s home to thousands of incredible creatures. Most of the life on the planet is in the water and there are so many species in the ocean we still don’t know a lot about. That’s where marine biologists come in. The job of a marine biologist is to study marine life, creatures that live in water, and their environment. Most people think the ocean is just full of fish, but there’s so much more in the ocean like plants, algae, fungi, and microscopic life. Since the word “marine” specifically refers to saltwater environments like oceans or places where saltwater and freshwater mix like wetlands, marine biologists typically only focus on the ocean, not lakes, rivers, or streams. They research everything from giant whales and sharks to the tiniest bacteria to learn how they live and interact with one another.

What Does a Marine Biologist Do?

Marine biology is the study of life in the ocean. The ocean is so big that it takes up about two-thirds of the planet’s surface and it holds many different types of creatures in its waters: potentially about 2.2 million species, even though only about 240,000 have been discovered so far. It’s estimated that scientists have only explored about 5% of the ocean and we can only guess at what else is out there that we haven’t learned about yet.

Part of a marine biologist’s job is to learn more about the species we know exist and also dig deep to discover what else is out there and their unique role in the ocean’s ecosystem. To do this, marine biologists learn about a wide variety of sciences from astronomy to zoology while also using the scientific method. The scientific method requires making an observation, researching, coming up with a hypothesis, testing that hypothesis, analyzing the data, and reporting the conclusion. Marine biologists use all these steps in their field of study while learning about the millions of different varieties of ocean life. However, there’s no one specific type of marine biologist, it’s a huge field and there are plenty of different sub-fields:

• Deep Sea Ecology – Using new technological advances to explore the deep sea which is a largely unknown part of the ocean to find alternate energy sources, new forms of marine life, and how those factors influence their biological community.
• Environmental Marine Biology – The study of ocean health and how the health of the ocean impacts and contributes to the global environmental health.
• Fisheries and Aquaculture – For some marine biologists who focus on fish, their goal is to protect biodiversity and create sustainable seafood sources.
• Ichthyology – The study of both saltwater and freshwater fish.
• Marine Ethology – Learning about the behavior of marine animals to better understand them and to help protect different species, especially the ones that are endangered.
• Marine Mammalogy – Studying cetaceans like whales, dolphins, sea lions, seals, and walruses. These scientists focus on learning about their behaviors, health, habitat, reproductive habits, and population.
• Microbiology – The study of microorganisms like algae, bacteria, protozoa, and viruses.

Why Study Marine Biology?

People have been fascinated by the ocean for thousands of years and learning more about it is a great way to get a better understanding of the world we live in. Given the chance to learn more about the ocean and the other marine life deep in its depths, we can help support the health of the ocean and planet as a whole as well as human health, create more sustainable ways to help issues like overfishing, impacts on the food chain, and dwindling species, and we can also do more research on alternative energy sources and medicine. There’s so much to learn in the ocean and the goal of marine biologists is to find new information to help better the planet.

How to Become a Marine Biologist

The most important thing any student needs to become a marine biologist is a love and appreciation for the ocean and all the life in it because, without that passion, it’s going to be hard to stay focused on all the classes you have to take. In school, you’ll need to focus on science and math courses, especially biology, physics, and chemistry. These courses will act as the building blocks of your future career because they will teach you how to collect and analyze biological data, identify species, study plant life, research the environmental effects of the ocean and the life within it, and then communicate those findings with the public as a whole.

• What is Marine Biology?
• Explore: What is Marine Biology?
• A Fun Guide to Teaching Kids About Marine Biology
• How To Become a Marine Biologist
• Marine Biology Facts: Lesson for Kids
• What Does a Marine Biologist Do?
• Marine Biology
• Skills for a Marine Biologist
• Ocean Habitat
• AWARE Kids Guide (PDF)
• Learn More: What are Marine Habitats?
• Climate Change and Ocean Currents Activity
• Admiralty and Maritime Law
• Deep Sea Biology
• How Will Changing Ocean Chemistry Affect the Shellfish We Eat?
• So You Want to Become a Marine Biologist?

This page was last updated by Douglas R. Williams