PASSIONATE ABOUT THE OCEAN?

Night dive for nudibranch research during the Sea Slug Ecology course at Black Turtle Conservation, Koh Tao.
Divers conducting sea slug monitoring surveys to study species diversity and distribution around Koh Tao.
Colorful Coryphellina nudibranch feeding on a coral reef in Koh Tao, Thailand, during a marine biodiversity survey.
Sea slug (Costasiella sp.) photographed during the Sea Slug Ecology course at Black Turtle Conservation, exploring nudibranch identification and behavior in Koh Tao, Thailand.

Sea slugs — including nudibranchs — are among the most fascinating and diverse animals on our reefs.

These tiny, vibrant marine gastropods come in an incredible variety of shapes, colors, and behaviors, and play a key ecological role as indicators of reef biodiversity and health.

In this 1-day hands-on course, you’ll explore the entire world of sea slugs — from colorful nudibranchs to other lesser-known but equally important species. You’ll learn how to identify, record, and monitor their diversity while contributing to an ongoing research project on sea slug ecology and biodiversity around Koh Tao.

Sea slugs — including nudibranchs, sacoglossans, and other marine gastropods — are soft-bodied mollusks renowned for their vivid colors, intricate shapes, and extraordinary diversity.

Despite their small size, they play a major ecological role in coral reef ecosystems: many are specialized feeders that help regulate sponge, coral, and algal populations, while others serve as key indicators of biodiversity and habitat complexity.

Our Nudibranch & Sea Slug Ecology Course will teach you how to identify different families and genera, understand their ecological importance, and collect real scientific data through structured underwater surveys.

You’ll also learn how sea slug communities respond to environmental changes — making them powerful bioindicators for assessing reef health and resilience in conservation research.

What you’ll learn:

  • Identify the main families and genera of sea slugs.
  • Understand their feeding strategies, reproduction, and defense mechanisms.
  • Conduct biodiversity and abundance surveys following scientific protocols.
  • Collect and record data for ongoing reef-monitoring and species-distribution projects.

This course is ideal if you want to:

  • Deepen your knowledge of marine invertebrate ecology.
  • Participate in real-world scientific research projects.
  • Build the observation and photography skills needed for biodiversity monitoring.
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WHY THIS COURSE MATTERS

Sea slugs are not only beautiful — they are scientific storytellers of the reef. Because many species are highly sensitive to changes in habitat complexity, pollution, and temperature, studying their distribution helps scientists detect subtle shifts in reef health before larger impacts occur.

By learning how to survey and identify these creatures, you’re contributing to one of Black Turtle Conservation’s ongoing research projects on sea slug biodiversity in Koh Tao. The data collected by students is used to analyze correlations between substrate complexity, reef type, and sea-slug diversity — helping us understand how different habitats influence marine life abundance.

Through this course, you’ll become part of a growing citizen-science movement that turns diving into real marine-research action.

price

6,000 THB

DURATION

1 day

classes

1 class

DIVES

2 training dives

CERTIFICATION

Conservation Diver

LEVEL REQUIRED

Advanced Open Water* Ecological Monitoring Program (EMP)
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* Not a diver yet? No problem! You can start your journey by learning to dive with us.
Our PADI Open Water and Advanced Open Water courses are the perfect first step before joining our marine conservation programs.

START WITH A DIVING COURSE

COURSE STRUCTURE

This Nudibranch & Sea Slug Ecology Course combines classroom learning, field observation, and real data collection to give you a complete understanding of sea slug ecology and identification.

Sea Slug Ecology

Day 1
Morning 09:00 Sea Slug Lecture
Lunch
Afternoon 12:00 Sea Slug Dive
15:00 Sea Slug Dive
Evening 17:00 Debrief

* Please note that the following schedule is indicative and may vary.
* Exact times for each session and dive will be confirmed before the course begins.

Morning — Theory Session

You’ll begin with an engaging presentation introducing the world of sea slugs — from their taxonomy and evolution to their ecological importance. Learn how to identify key families, recognize their feeding behaviors, and understand their roles in the reef food web.

You’ll also study the methods used in marine biodiversity surveys, including how to conduct systematic searches and record ecological data effectively.

Afternoon — 2 Research Dives

Dive 1: Sea Slug Biodiversity Survey

Conduct a structured roving survey to locate and identify sea slugs in their natural habitats. You’ll document species using photography and log substrate data for analysis.

Dive 2: Habitat & Abundance Monitoring

Continue your search at a different site, comparing sea slug diversity across reef types while collecting data for our long-term study on habitat complexity and species richness.

After the dives, you’ll review your photos and data with your instructor, contributing your findings to our Sea Slug Research Database, part of an ongoing project that has already recorded dozens of species across Koh Tao.

By the end of the day, you’ll be able to confidently identify key sea slug families, understand their ecological significance, and assist in biodiversity monitoring anywhere in the world.

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Price:
6,000 ฿
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Includes:
  • Conservation Diver E-Learning
  • 1 class
  • 2 guided conservation dives
  • Conservation Diver Certification
  • Diving equipment & dive computer
  • Dive insurance
  • Refreshments & fruit on the boat
Prerequisites:
  • Advanced Open Water Diver (or equivalent)
  • Completion of the Ecological Monitoring Program (EMP)

Testimonials 

   
 
 
 
 
 
 
 
 
 
 
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 Chee yen Wong 
 
1 days ago
 
 
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+1
This dive shop is highly recommended!
The diving guide Isbella is very professional, enthusiastic and patient in explaining everything.
  
 
 
 
 
 
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 matthias p 
 
1 days ago
 
 
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Ich war jetzt bereits zum wiederholten Male tauchen bei Black Turtle Dive und bin begeistert. Der Service, die Hilfsbereitschaft & Professionalität sind überragend!

Vor allem meine Fun Dives mit den Dive Master Nils und Hailey waren perfekt.

Danke für diese tolle Erfahrung!!
  
 
 
 
 
 
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 Amy Burnett 
 
2 days ago
 
 
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+0
If you’re looking to complete your PADI open water course, I could not recommend Black Turtle Dive more. We completed the 3 day course. Learnt so much about the ocean and the safety behind diving, that we can take forward to any future dives.
Our instructors Jaa and Arisa were so encouraging and patient when it came to learning new skills.
As well as the incredible dive locations they take you too.
  
 
 
 
 
 
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 Zoe Clark 
 
2 days ago
 
 
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If I could give more than 5 stars I would. The staff were so friendly and welcoming as soon as we stepped through the door.
Our instructors were more than perfect Jaa and arisa. Could not recommend them more. Hope to dive with them again sometime. Highly recommend
  
 
 
 
 
 
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 Alya F profile picture 
 
 
 Alya F 
 
3 days ago
 
 
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Ich durfte meinen Open Water Diver hier absolvieren und war wirklich sehr zufrieden. Meine Tauchlehrerin war Nadine, sie ist wirklich mega super! Ich habe mich in der Ausbildung immer sehr wohl und verstanden gefühlt. Sie hat mich immer mit viel Geduld und Passion in meinem Lernprozess begleitet, VIELEN DANK Nadine!
Ich schätze generell bei Black Turtle die Professionalität und Hilfsbereitschaft sehr! Man merkt das sie viel Leidenschaft im Tauchen leben (das ganze Team) und ihnen Sicherheit beim Tauchen sehr wichtig ist. Ich habe mich vom Empfang bis zur letzen Ausbildungseinheit gut betreut und beraten gefühlt. Komme gerne wieder 🤟🏼
  
 
 
 
 
 
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 Federico Bertorello 
 
4 days ago
 
 
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Hice el curso de open water, la atención de las chicas 10! Mi instructora Rhi excelente!
  
 
 
 
 
 
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 Toby profile picture 
 
 
 Toby 
 
4 days ago
 
 
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If your looking for low cost, high quality dive school to do your scuba open waters and/or more through, black turtle is the place to go.  Ask around for an instructor named Naim and a soon-to-be instructor named Annie.  They were great company and even better instructors.  Strongly recommend.
  
 
 
 
 
 
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 Miriam schlenker 
 
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 Michael Clarke profile picture 
 
 
 Michael Clarke 
 
4 days ago
 
 
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Chae was awesome. Super patient and helpful with the refresher course we did together.

I had some serious trouble equalising and he kept me calm, was really understanding, and managed to get me down for two great experiences.

Totally recommend him and the whole staff.
  
 
 
 
 
 
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 Mats Lory 
 
5 days ago
 
 
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Amazing dive center, super professional and chill people!
Marine conservation diver photographing nudibranch species on Koh Tao coral reef as part of biodiversity documentation.

Keep Learning

Continue your conservation journey with complementary specialty courses that expand your research and monitoring skills:

Coral Disease & Compromised Health – Learn to recognize early signs of coral stress, overgrowth, and disease patterns.

Coral Restoration – Explore restoration methods and contribute to real rehabilitation projects.

Artificial Reefs – Study how engineered reef structures enhance biodiversity and provide new marine habitats.

Advanced Coral Taxonomy – Master the identification of rare and complex coral genera across the Indo-Pacific.

Advanced EMP – Apply advanced monitoring techniques and design your own research protocols.

Each course builds on your Nudibranch & Sea Slug Ecology training, strengthening your ability to conduct real marine biodiversity studies and contribute to long-term conservation research.

Scuba diver conducting an ecological monitoring survey along a transect line during the EMP marine conservation course with Black Turtle Conservation in Koh Tao, Thailand.

ECOLOGICAL MONITORING PROGRAM

Prerequisites: AOW

The Ecological Monitoring Program (EMP) introduces reef survey methods and scientific diving techniques. You’ll learn to assess fish, invertebrates, substrate, and coral health, and report your findings to an international database.

4 days 6 dives 11,900 ฿
Close-up photo of branching coral polyps used in the Coral Taxonomy I course at Black Turtle Conservation, Koh Tao, Thailand.

Coral Taxonomy & Identification

Prerequisites: AOW + EMP

Learn to identify coral species based on skeletal and anatomical characteristics, both on land and underwater.

This course builds essential skills for research, restoration, and monitoring projects.

1 day 2 dives 6,000 ฿
Sea slug (Costasiella sp.) photographed during the Sea Slug Ecology course at Black Turtle Conservation, exploring nudibranch identification and behavior in Koh Tao, Thailand.

NUDIBRANCH & SEA SLUG ECOLOGY

Prerequisites: AOW + EMP

Dive into the world of nudibranchs and sea slugs, key indicators of reef biodiversity and water quality. You’ll explore their taxonomy and ecology while participating in an ongoing research project at Black Turtle Conservation.

1 day 2 dives 6,000 ฿
Diver restoring corals by attaching fragments on artificial reef structures during the Coral Restoration course with Black Turtle Conservation in Koh Tao, Thailand.

CORAL RESTORATION THEORY & TECHNIQUES

Prerequisites: AOW + EMP

Explore the science behind coral restoration.

You'll learn about restoration strategies, site selection, coral health assessment, and attachment methods.

1 day 2 dives 8,000 ฿
Marine conservation divers assembling artificial reef modules underwater during the Artificial Reefs course at Black Turtle Conservation, Koh Tao, Thailand.

ARTIFICIAL REEF THEORY & TECHNIQUES

Prerequisites: AOW + EMP + Coral Restoration

Artificial reefs help restore damaged habitats and provide alternative dive sites. You’ll explore the science behind their design and even create your own reef project as a classroom exercise.

1 day 2 dives 6,000 ฿
Crown-of-thorns starfish (Acanthaster planci), a major coral predator, documented during the Coral Predators course with Black Turtle Conservation in Koh Tao, Thailand.

CORAL PREDATORS: POPULATION MANAGEMENT & MONITORING

Prerequisites: AOW + EMP

Identify and monitor coral predators such as crown-of-thorns starfish and Drupella snails, and understand their impact on reef health.

This course teaches practical techniques for population control and long-term reef protection.

1 day 2 dives 6,000 ฿
Detailed macro image of coral polyps used in the Advanced Coral Taxonomy course to teach species-level identification with Black Turtle Conservation in Koh Tao, Thailand.

ADVANCED CORAL TAXONOMY

Prerequisites: AOW + EMP + Coral Taxonomy

Expand your coral identification skills by learning to recognize more challenging and rare genera.

This course deepens your knowledge of skeletal and anatomical traits, strengthening your abilities for advanced research and monitoring.

2 days 4 dives 10,000 ฿
Bleached coral branch showing disease patterns used for training during the Coral Disease course at Black Turtle Conservation in Koh Tao, Thailand.

CORAL DISEASES & COMPROMISED HEALTH

Prerequisites: AOW + EMP + Coral Taxonomy

Discover how to identify and record common coral diseases and signs of stress in reef ecosystems.

This course equips you with the skills to assess reef health and contribute valuable data to monitoring efforts.

1 day 2 dives 6,000 ฿
Green sea turtle resting on a coral reef while snorkelers observe from the surface during the Sea Turtle Ecology and Identification course at Black Turtle Conservation, Koh Tao, Thailand.

ADVANCED EMP

Prerequisites: AOW + EMP + Coral Taxonomy + Coral Disease + 3 Monitoring Courses

Gain experience using additional monitoring techniques, including quadrants, transects, and advanced survey methods. This course enhances your ability to collect accurate data and analyze long-term changes in reef ecosystems.

1 day 2 dives 6,000 ฿
Scientific diver performing advanced coral reef monitoring using quadrats during the Advanced Ecological Monitoring Program (EMP) course with Black Turtle Conservation in Koh Tao, Thailand.

SEA TURTLE ECOLOGY & MONITORING

Learn about the ecology, behavior and threats facing sea turtles, all of which are endangered. Develop skills in turtle ID and data collection, allowing you to contribute to real conservation initiatives by recording sightings to support ongoing monitoring efforts in Koh Tao and internationally.

1 day 1 snorkel 6,000 ฿
Group of marine conservation divers studying shark behavior and population ecology during the Shark Ecology course at Black Turtle Conservation, Koh Tao, Thailand.

SHARK ECOLOGY & POPULATION STUDIES

Sharks play a crucial role as apex predators, yet many species are now critically endangered. Explore their evolution, anatomy, and ecological role. Learn population monitoring techniques and how to contribute to local and global shark databases to aid conservation efforts.

1 day 1 snorkel 6,000 ฿
Coral Watch coral health chart being used to assess coral bleaching levels during the Coral Watch course with Black Turtle Conservation on Koh Tao, Thailand.

CORAL WATCH SPECIALITY

Learn how to assess coral health and contribute to a global monitoring effort using a powerful method developed by CoralWatch and supported by PADI AWARE. Gain insight into coral biology, bleaching, and climate change, while participating in real reef surveys.

1 day 1 snorkel or 2 dives 6,000 ฿
Students conducting a beach microplastic survey using quadrats during the Plastic Pollution Monitoring & Assessment course at Black Turtle Conservation, Koh Tao, Thailand.

PLASTIC POLLUTION: MONITORING & ASSESSMENT

Learn about the scale and impact of plastic pollution in the ocean. Gain hands-on experience monitoring microplastics and help protect reef ecosystems by removing macroplastics.

1 day 1 beach clean up, 1 snorkel or 2 dives 6,000 ฿
Open Water Diver training session in clear tropical waters, ideal conditions for learning safe and controlled scuba diving in Koh Tao.

3 DAY PADI OPEN WATER DIVER

3 days 5 Confined Dives, 4 Ocean Dives 12,950 ฿
Advanced Open Water Diver training with a strong focus on safety, control, and relaxed diving techniques in Koh Tao, Thailand.

PADI ADVANCED OPEN WATER DIVER

2 days 5 Adventure Dives in the Ocean 11,900 ฿
Rescue Diver student practicing underwater emergency response skills and regulator management in a controlled training environment in Koh Tao.

PADI RESCUE DIVER + EMERGENCY FIRST RESPONSE (EFR)

3-4 days Focus: Self-rescue diver assistance, emergency management 18,000 ฿
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Grow Your Skills with Our Conservation Programs

All our marine conservation programs begin with the Ecological Monitoring Program (EMP), providing a solid foundation in scientific diving and hands-on conservation.

From there, you can continue learning through our carefully designed programs, which follow a progression we’ve developed to maximize learning and practical experience. Each course builds on the last, helping you develop your skills step by step while contributing to meaningful conservation projects.

Whether your goal is to specialize in coral restoration, turtle research, or broader reef monitoring, our programs guide you along a clear path, so you can grow as a marine conservationist while enjoying every step of the journey.

Marine conservation students conducting coral reef surveys during the Core Conservationist one-week program with Black Turtle Conservation in Koh Tao, Thailand.

CORE CONSERVATIONIST

  • EMP
  • Coral Taxonomy
1 week 19,900 ฿
Two marine conservation divers collecting coral reef monitoring data underwater during the Conservation Specialist two-week program at Black Turtle Conservation, Koh Tao, Thailand.

CONSERVATION SPECIALIST

  • EMP
  • Coral Taxonomy
  • Sea turtles
  • BTD Sea slugs
2 weeks 33,000 ฿
Diver inspecting coral restoration structures during the Reef Conservationist four-week program with Black Turtle Conservation in Koh Tao, Thailand.

REEF SPECIALIST

  • Coral Restoration
  • Artificial Reefs
  • Coral Taxonomy III
  • BTC Marine Pollution
+ 2 weeks 30,000 ฿
Marine conservation divers conducting advanced ecological monitoring surveys during the Master Conservationist six-week program at Black Turtle Conservation, Koh Tao, Thailand.

MASTER CONSERVATIONIST

  • Giant Clams
  • BTD Cleaning Stations
  • BTD Coral Predators
  • Sharks
+ 2 weeks 30,000 ฿
Marine scientists and conservation divers conducting long-term reef monitoring and research as part of the Scientific Diver eight-week program with Black Turtle Conservation, Koh Tao, Thailand.

SCIENTIFIC DIVER

  • Image J
  • Coral Disease
  • Advanced EMP
+ 2 weeks 30,000 ฿

Learning Pathway

Black Turtle Conservation Learning Pathway
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FREQUENTLY ASKED QUESTIONS

What is the Nudibranch & Sea Slug Ecology course at Black Turtle Conservation?

The Nudibranch & Sea Slug Ecology course is a 1-day marine conservation training designed to explore the fascinating diversity and ecological importance of sea slugs — including nudibranchs, sacoglossans, and other marine gastropods.

Through engaging classroom sessions and guided dives, you’ll learn to identify, monitor, and record sea slug species while contributing to an ongoing biodiversity research project on Koh Tao’s coral reefs.

Why are nudibranchs and sea slugs important for marine conservation?

Nudibranchs and other sea slugs are vital bioindicators of coral reef health. Many species are highly specialized, feeding only on specific sponges, corals, or algae, which makes them sensitive to habitat changes.

Monitoring their abundance and diversity helps scientists understand how reef ecosystems respond to environmental stress, making these creatures key to effective conservation research.

What will I learn during the Nudibranch & Sea Slug Ecology course?

You’ll learn how to identify the most common families and genera of sea slugs found in the Indo-Pacific region, understand their ecological roles, and collect scientific data using professional biodiversity monitoring techniques.

You’ll also practice underwater observation and macro photography to document species and contribute data to active research projects.

Do I need to be a certified diver to take part in the Nudibranch & Sea Slug Ecology course?

Yes. To enroll, you must be an Advanced Open Water Diver (or equivalent) and have completed the Ecological Monitoring Program (EMP). These prerequisites ensure participants have the necessary diving and ecological background to safely and effectively take part in scientific surveys.

Where does the Nudibranch & Sea Slug Ecology course take place in Koh Tao?

The course takes place at Koh Tao’s most biodiverse reefs, selected for their varied habitats and rich invertebrate life. Sites often include sandy slopes, coral gardens, and rubble patches — ideal for spotting a wide range of sea slug species, including rare nudibranchs that thrive in specific microhabitats.

Will I contribute to real marine research during the Nudibranch & Sea Slug Ecology course?

Absolutely! Students actively participate in Black Turtle Conservation’s long-term sea slug biodiversity project, which studies how habitat complexity affects species diversity. The data you collect is added to our scientific database and contributes to ongoing conservation research in collaboration with marine scientists across Thailand.

What makes the Nudibranch & Sea Slug Ecology course unique in Thailand?

Unlike typical marine biology courses, this program combines scientific fieldwork, hands-on training, and real research participation. You’ll work with marine biologists and Conservation Diver Instructor Trainers who are conducting active biodiversity studies. It’s an opportunity to practice real science underwater — not just observe.

What kinds of sea slugs will I see during the course?

Koh Tao is home to an extraordinary variety of sea slugs — from vibrant Phyllidia and Coryphellina nudibranchs to the more elusive Costasiella sacoglossans and Phestilla nudibranchs. Each dive offers the chance to discover new and unexpected species, adding excitement and a sense of exploration to every survey.

Can I combine the Nudibranch & Sea Slug Ecology course with other marine conservation training?

Yes! The Nudibranch & Sea Slug Ecology course pairs perfectly with other conservation specialties such as Sea Turtle Ecology, Coral Predators or Giant Clams.

It’s also a core module of our Conservation Specialist Program, which allows you to expand your marine research skills over multiple courses.

Why take the Nudibranch & Sea Slug Ecology course with Black Turtle Conservation in Koh Tao?

At Black Turtle Conservation, you’ll be part of a real scientific team studying sea slug biodiversity and its relationship with reef complexity. Our experienced marine conservationist guide you through every step — from species identification to data collection — making the experience hands-on, engaging, and scientifically meaningful.

You’ll leave not only with a Conservation Diver certification, but also with valuable research experience and a deeper connection to the reef ecosystem.

Still have questions?

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