Updated October 2026

TL;DR

Marine biology lets you study anything from tiny plankton to whales, and from coral reefs to the fishing towns that depend on them. This guide gives you a set of 35 research ideas, plus two tables that sort them by how much time you have and what kind of evidence you will use. If you want to turn one idea into a full paper with one-on-one guidance from a PhD mentor, you can apply to the Lumiere Research Scholar Program.

If you’re a high school student interested in marine biology and want to explore a research topic of your own, this guide can help you get started. It covers 35 research ideas in marine biology, ranging from marine ecosystems and animal behavior to ocean pollution, conservation, and climate change. You can explore different areas of the field and see which topics match your interests. Each idea can also give you a starting point for developing your own research question. If you are not sure where to begin, read our guide on how to choose a research mentor and subject area.

Why is marine biology a strong field for a research project?

Marine biology connects to chemistry, genetics, economics, policy, and data science. You do not have to be a diver or live near the coast to find a question that suits you. You can work with numbers, with DNA records, with video, or with interviews. That flexibility means you can choose a project that fits the skills and tools you already have.

How do you shrink a huge ocean topic into one question?

"Coral reefs" is a subject. "How did bleaching change one reef over ten years?" is a question you can answer. To get from one to the other, choose one place, one species, or one time period, then ask what you could count or compare.

If you can name the data you would collect, the question is ready. For more on the early steps, see our guide to starting out with research in high school.

What should you check before you start?

Do not handle or disturb wild animals for a project. Check local rules before you collect any water, sand, or other samples. If you survey or interview people, tell them how you will use their answers, keep names out of your paper, and get a parent or guardian's consent if they are under 18.

Finally, write your question and your plan for collecting evidence in a few sentences before you begin. When you are ready to write up your results, our guide on how to publish a research paper in high school explains the next steps.

Which marine biology research topic fits your interests?

With so many areas to explore, it can help to start with the part of marine biology you find most interesting. This table groups some of the ideas below by broad interest area, so you can quickly find a topic that matches what you want to study.

Climate change and ocean life

Climate change affects marine ecosystems in different ways, from changing water temperatures to shifting coastlines and oxygen levels. These topics let you investigate one specific environmental change and its effect on marine life.

1. Fish migration and rising water temperatures

Choose one region and track how fish migration patterns have changed alongside water temperatures. Focus on a few species so you can compare their movements with temperature records over the same period.

Research question: How have rising water temperatures affected the migration patterns of fish in one region?

What you'll need: Published fish migration records, sea-temperature data, species reports, and a spreadsheet for comparing changes over time.

A good fit if you like: Marine ecosystems, climate science, and working with environmental data.

2. Ocean acidification and marine life

Look at how increasing carbon dioxide levels in seawater affect shellfish or plankton. You can then examine how changes in these organisms could affect the coastal communities that depend on them.

Research question: How does ocean acidification affect shellfish or plankton in a particular marine ecosystem?

What you'll need: Published ocean-acidification studies, shellfish or plankton data, environmental reports, and basic data-analysis tools.

A good fit if you like: Chemistry, marine ecosystems, and the effects of climate change.

3. Coral bleaching on one reef

Choose one coral reef with several years of available records. Compare changes in water temperature with bleaching events and examine what happened to coral growth or reef health afterward.

Research question: How have changes in water temperature affected coral bleaching on one reef over time?

What you'll need: Coral-monitoring reports, sea-temperature records, satellite images or photographs, and a spreadsheet.

A good fit if you like: Coral reefs, climate change, and visual or environmental data.

4. Storms and ocean warming

Compare historical storm records with sea-surface temperature data for a defined region. Look for patterns in storm frequency or intensity without assuming that temperature alone explains the changes.

Research question: What relationship can be found between ocean temperatures and changes in storm activity in one region?

What you'll need: Historical storm records, sea-temperature datasets, climate reports, and a spreadsheet or charting tool.

A good fit if you like: Climate science, weather, and finding patterns in large datasets.

5. Low-oxygen zones in the ocean

Map where low-oxygen or hypoxic zones have appeared and examine how their expansion affects marine species. Focus on one region or time period to keep the project manageable.

Research question: How have expanding low-oxygen zones affected the distribution of marine animals in one region?

What you'll need: Ocean oxygen datasets, species-distribution records, maps, and a spreadsheet or mapping tool.

A good fit if you like: Marine ecology, maps, and environmental data.

6. Rising seas and nesting habitats

Choose sea turtles or shorebirds in one coastal area and compare nesting records with changes in the shoreline. Look at whether changes in beaches or sea levels correspond with changes in available nesting habitat.

Research question: How have rising sea levels affected nesting habitats for one coastal species?

What you'll need: Nesting records, shoreline or satellite data, sea-level information, and mapping software.

A good fit if you like: Wildlife, climate change, and conservation.

Coastal economies and communities

Marine ecosystems are closely connected to the people who live and work near them. These topics let you examine how fishing, tourism, conservation, and pollution affect both marine environments and coastal communities.

7. Comparing coastal management policies

Choose two countries or coastal regions and compare how each manages its marine resources. Look at how their policies balance economic activity with environmental protection.

Research question: How do two coastal regions differ in the way they balance economic activity with marine conservation?

What you'll need: Government policy documents, environmental reports, economic data, and a comparison table.

A good fit if you like: Environmental policy, economics, and comparing different approaches.

8. Tourism and marine conservation

Choose a coastal tourist destination and examine how tourism affects its marine environment. Then investigate which conservation measures are being used and whether published evidence suggests they are working.

Research question: How can tourism support marine conservation while limiting damage to a coastal ecosystem?

What you'll need: Tourism statistics, conservation reports, environmental studies, and information from local authorities.

A good fit if you like: Tourism, environmental policy, and real-world conservation problems.

9. Sustainable seafood and fishing communities

Compare different sustainable fishing methods and consider their environmental and economic effects. You can focus on one fishery to make the comparison more specific.

Research question: Which sustainable fishing methods can reduce environmental damage while supporting fishing communities?

What you'll need: Fisheries reports, sustainability studies, catch data, and information about fishing costs and income.

A good fit if you like: Marine conservation, economics, and food systems.

10. Marine pollution and fishing income

Follow one source of pollution, such as agricultural runoff or industrial waste, and examine how it affects marine habitats and fishing activity.

Research question: How can marine pollution affect fishing income and the health of nearby marine ecosystems?

What you'll need: Pollution records, fisheries data, environmental studies, and local economic reports.

A good fit if you like: Environmental science, economics, and cause-and-effect research.

Marine genomics

DNA research gives you another way to study marine organisms, from tracking species through environmental DNA to comparing genetic differences between populations.

11. Environmental DNA for tracking marine species

Environmental DNA, or eDNA, refers to genetic material that organisms leave behind in water. Investigate how scientists use these traces to detect species without having to capture or observe them directly.

Research question: How effective is environmental DNA for detecting marine species in a particular ecosystem?

What you'll need: Published eDNA studies, species-detection data, genetics resources, and a spreadsheet for comparing results.

A good fit if you like: Genetics, marine conservation, and emerging research methods.

12. Genetic diversity and marine species

Choose one marine species and examine how pollution, overfishing, habitat loss, or other pressures may affect its genetic diversity. Focus on published genetic studies rather than trying to collect samples yourself.

Research question: How have environmental pressures affected genetic diversity in one marine species?

What you'll need: Published genetic studies, species databases, conservation reports, and basic data-analysis tools.

A good fit if you like: Genetics, evolution, and conservation.

13. Comparing marine genomes

Choose two marine species and compare selected parts of their genomes. You can then connect genetic differences with differences in habitat, physical traits, or behavior.

Research question: What can genetic differences between two marine species tell us about how they adapted to their environments?

What you'll need: Public genome databases, species information, basic genetics resources, and comparison tools.

A good fit if you like: Biology, genetics, and working with large datasets.

14. Tracking seafood through genetics

Investigate how genetic testing can identify the species in seafood products. Review published studies that tested whether seafood labels matched the species actually sold.

Research question: How accurately can genetic testing identify the species found in commercial seafood?

What you'll need: Published seafood-authentication studies, DNA databases, species records, and research on food labeling.

A good fit if you like: Genetics, food science, and real-world applications of biology.

Ocean-based solutions

Marine ecosystems can also be part of efforts to restore habitats, capture carbon, produce food, and reduce environmental damage. These ideas focus on whether those solutions actually work.

15. Artificial reefs and biodiversity

Compare a restored or artificial reef with a nearby natural or unrestored site. Look at differences in species numbers, habitat use, or other measures of biodiversity.

Research question: Do artificial reefs or habitat-restoration projects increase marine biodiversity?

What you'll need: Biodiversity surveys, restoration studies, species counts, and environmental reports.

A good fit if you like: Conservation, ecology, and comparing ecosystems.

16. Plastic pollution and biodegradable alternatives

Examine how plastic affects marine organisms and investigate whether biodegradable alternatives could reduce some of those effects. Keep the project focused on one type of plastic or organism.

Research question: Could biodegradable packaging reduce one specific type of harm caused by plastic pollution in marine environments?

What you'll need: Marine-plastic studies, research on biodegradable materials, pollution data, and a comparison framework.

A good fit if you like: Environmental science, materials, and pollution research.

17. Blue carbon ecosystems

Study how mangroves, salt marshes, or seagrass beds capture and store carbon. Choose one ecosystem and estimate how much carbon it can hold based on published measurements.

Research question: How much carbon can one coastal ecosystem store, and what factors affect its capacity?

What you'll need: Carbon-storage studies, ecosystem data, published measurements, and a spreadsheet.

A good fit if you like: Climate change, ecology, and quantitative research.

18. Offshore wind farms and marine life

Examine research on how offshore wind farms affect fish, seabirds, and marine mammals. Compare evidence collected before and after construction or between areas with and without wind farms.

Research question: How do offshore wind farms affect marine animals living nearby?

What you'll need: Environmental impact assessments, wildlife-monitoring data, published studies, and before-and-after comparisons.

A good fit if you like: Renewable energy, marine ecology, and environmental trade-offs.

Marine animal behavior

You can study marine animal behavior without observing animals yourself. Published videos, recordings, tracking data, and field studies provide plenty of material for asking focused questions.

19. Boat noise and whale communication

Compare recordings of whales or dolphins from areas with different levels of boat traffic. Look for differences in call frequency, duration, or other measurable features.

Research question: How does boat noise affect the communication behavior of whales or dolphins?

What you'll need: Published underwater recordings, acoustic studies, audio-analysis software, and a small set of comparison samples.

A good fit if you like: Animal behavior, sound, and marine conservation.

20. How sea turtles navigate

Investigate the main explanations for how sea turtles find their way back to nesting beaches. Compare evidence for mechanisms such as magnetic sensing, visual cues, and environmental signals.

Research question: Which evidence best supports the leading explanations for how sea turtles navigate?

What you'll need: Published turtle-navigation studies, tracking research, scientific reviews, and a system for comparing evidence.

A good fit if you like: Animal behavior, biology, and evaluating scientific explanations.

21. Seabird feeding patterns

Use tracking data or published observations to investigate where seabirds feed and how their movements relate to the availability of fish.

Research question: How do seabird feeding trips change in response to the location or availability of prey?

What you'll need: Bird-tracking datasets, feeding observations, fish-distribution data, and mapping tools.

A good fit if you like: Birds, animal movement, and data visualization.

22. Problem-solving in octopuses

Compare experiments that test octopus learning and problem-solving with observations from natural environments. Focus on one specific behavior instead of trying to measure intelligence as a whole.

Research question: What do octopus problem-solving behaviors reveal about learning and intelligence in marine animals?

What you'll need: Published behavioral experiments, video observations, scientific reviews, and a comparison framework.

A good fit if you like: Animal intelligence, psychology, and unusual marine species.

Plankton and ocean microbes

Plankton and microbes are small but essential to marine food webs and global carbon cycles. Their abundance and behavior can also reveal changes in ocean conditions.

23. Seasonal changes in plankton

Choose one bay, harbor, or coastal area and examine plankton counts across different seasons. Compare changes in abundance with temperature, sunlight, or other environmental factors.

Research question: How does plankton abundance change across seasons in one marine environment?

What you'll need: Published plankton counts, temperature and light data, environmental records, and a spreadsheet.

A good fit if you like: Ecology, environmental data, and seasonal patterns.

24. Harmful algal blooms

Investigate what causes harmful algal blooms and what happens to fish, other marine organisms, or people when they occur. Compare several bloom events to identify common environmental conditions.

Research question: Which environmental factors are associated with harmful algal blooms in one region?

What you'll need: Algal-bloom records, weather and water-quality data, environmental reports, and a spreadsheet.

A good fit if you like: Marine ecology, environmental health, and data analysis.

25. Microplastics in marine food webs

Examine how microplastics enter plankton and move into organisms that eat them. You can focus on one food chain and use published studies to trace the movement of plastic.

Research question: How do microplastics move through one marine food web?

What you'll need: Published microplastic studies, food-web data, species records, and a way to compare findings across studies.

A good fit if you like: Pollution, ecology, and environmental research.

Deep sea and polar ecosystems

Deep-sea and polar environments are difficult to study directly, but researchers have built large collections of observations and expedition data that you can use for a research project.

26. Life around hydrothermal vents

Explore how organisms survive around hydrothermal vents, where there is no sunlight and temperatures can change sharply. Focus on how they obtain energy and tolerate their surroundings.

Research question: How do organisms around hydrothermal vents survive without sunlight?

What you'll need: Deep-sea research papers, species profiles, food-web studies, and information about vent chemistry.

A good fit if you like: Extreme environments, ecology, and unusual organisms.

27. Deep-sea adaptations

Choose several species from different depths and compare the physical or biological features that help them survive under pressure and in darkness.

Research question: How do deep-sea animals adapt to increasing pressure and limited light?

What you'll need: Species databases, deep-sea studies, anatomical information, and a comparison table.

A good fit if you like: Evolution, anatomy, and extreme environments.

28. Sea-ice loss and polar food webs

Trace how declining sea ice affects organisms at different levels of a polar food web, beginning with algae and moving upward to larger animals.

Research question: How does sea-ice loss affect the structure of a polar marine food web?

What you'll need: Sea-ice datasets, food-web studies, species records, and a diagram or spreadsheet for mapping relationships.

A good fit if you like: Climate change, ecology, and interconnected systems.

29. Deep-sea mining and marine ecosystems

Examine what deep-sea mining could disturb on the seafloor and compare proposed mining activity with what researchers know about those habitats.

Research question: What could deep-sea mining mean for marine ecosystems in areas targeted for extraction?

What you'll need: Deep-sea habitat studies, mining proposals, environmental assessments, and conservation reports.

A good fit if you like: Marine conservation, environmental policy, and emerging scientific issues.

Ocean technology and data

Modern marine research increasingly relies on satellites, drones, sensors, tracking systems, and software. These topics work particularly well if you enjoy data or technology.

30. Mapping marine animals with satellite or drone images

Choose one species or habitat and use publicly available imagery to investigate how researchers identify and count marine animals or map reefs.

Research question: How accurately can satellite or drone imagery be used to monitor a particular marine species or habitat?

What you'll need: Public satellite or drone imagery, marine-monitoring studies, image-analysis tools, and a way to compare observations.

A good fit if you like: Technology, marine ecology, and visual data.

31. Monitoring ocean life through sound

Investigate how underwater sound recordings can reveal information about marine ecosystems. Compare recordings from healthy and disturbed environments if suitable datasets are available.

Research question: What can underwater sound recordings reveal about the health or activity of a marine ecosystem?

What you'll need: Public acoustic recordings, marine bioacoustics studies, audio software, and a method for comparing recordings.

A good fit if you like: Sound, technology, and animal behavior.

32. Tracking sharks or turtles across oceans

Use published tagging data to map the movements of sharks or sea turtles. Look for recurring migration routes, seasonal movements, or locations where animals gather.

Research question: What movement patterns appear in the tracking data of one shark or turtle species?

What you'll need: Public tracking datasets, species information, mapping software, and a spreadsheet.

A good fit if you like: Wildlife, geography, and data visualization.

33. Using AI to identify marine species

Explore how image-recognition systems can classify marine animals in photographs. Test a simple model or compare an existing tool's predictions with correctly identified images.

Research question: How accurately can an image-recognition system identify a particular group of marine species?

What you'll need: Marine-species photographs, an image-recognition tool or simple model, labeled examples, and a scoring system.

A good fit if you like: AI, coding, photography, and marine biology.

Conservation and species at risk

Conservation research asks whether specific protection measures are working and how human activities affect marine species.

34. Marine protected areas

Compare a marine protected area with nearby waters outside its boundaries. Look at measures such as fish abundance, species diversity, or average fish size.

Research question: Do marine protected areas show measurable differences in fish populations compared with nearby unprotected waters?

What you'll need: Fish surveys, biodiversity records, marine-protected-area reports, and a spreadsheet.

A good fit if you like: Conservation, ecology, and comparing real-world outcomes.

35. Reducing bycatch

Bycatch happens when fishing gear unintentionally catches animals that fishers did not intend to target. Compare different fishing methods and examine which approaches reduce bycatch and what they cost.

Research question: Which fishing methods are most effective at reducing bycatch while remaining practical for fishers?

What you'll need: Fisheries studies, bycatch statistics, information about fishing methods, and economic data.

A good fit if you like: Conservation, fisheries, and practical environmental solutions.

Some of these ideas were contributed by Lumiere mentors, including mentors from the University of San Diego.

If you want more projects in related fields, see our lists of biology research ideas and life sciences research topics, or read about environmental science research opportunities for high school students.

If you want to work on a marine biology question with a mentor, the Lumiere Research Scholar Program is a selective online program for high school students, founded with researchers at Harvard and Oxford. You choose a topic and work one on one with a PhD mentor to finish a research paper. Students from low income backgrounds can also look at the Lumiere Research Inclusion Foundation, a non profit research program.

Frequently asked questions about starting a marine biology project

1. Can you study an endangered species without ever seeing one in person?

Yes. Published survey counts, genome records, and tagging reports let you ask real questions about a species from your desk. Choose a species with plenty of published material so your question does not stall.

2. Can you research deep sea life if you live far from the ocean?

Yes. Deep sea and polar work relies on published recordings, sample records, and expedition reports rather than your own dives. Check that enough material exists before you settle on a question, since fewer people have studied these places.

3. Do any of these ideas need costly equipment?

It depends. Many ideas need only a laptop, a notebook, or a free tool, while sampling water or plankton may call for basic kits that a school lab can lend. Start with the cheapest version of your question and add equipment only if you need it.

4. Can one of these ideas become a full paper that you could submit?

Yes, as long as your question is narrow and you can show how you collected and checked your evidence. If you want a mentor to guide you from the first question to a finished paper, you can apply to the Lumiere Research Scholar Program.