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ABOUT THIS TOOLKIT

The Reef-World Foundation, the team coordinating Green Fins, a UNEP initiative, has created this toolkit in response to the 4th Global Coral Bleaching event. It aims to provide guidance on how the diving and snorkelling industry can help manage and monitor the impacts of coral bleaching. The toolkit is compiled of a mix of freely available resources from multiple organisations, as well as Green Fins materials, and will guide you through how you can help conserve and manage coral reefs in light of the growing impacts from climate change.

This toolkit will continue to be updated as new and relevant information becomes available.

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This toolkit is open for use worldwide.
Use the contents page to navigate the toolkit.
There are many tools and resources linked throughout this toolkit for you to explore and learn more. Just click the images, underlined text or to open a new tab to the resource.

If you have any questions or feedback please contact info@greenfins.net or start a discussion on Green Fins Community Forum.

This toolkit is available through Green Fins website.

This toolkit is for you if you are a:

HOW TO USE THIS TOOLKIT

DIVE CENTRE

DIVE PROFESSIONAL

DIVER

SNORKELLER

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EXPLORE THE TOOLKIT

WHAT IS CORAL BLEACHING
WHAT IS A GLOBAL CORAL BLEACHING EVENT
4th Global Coral Bleaching Event
WHAT CAN THE DIVING AND SNORKELLING INDUSTRY DO
Reduce Local Impacts
Briefing Your Guests
Monitor the Reefs
Assist Reef Recovery

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01.

WHAT IS CORAL BLEACHING

Photo credit: The Ocean Agency

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When corals are stressed by changes in conditions such as temperature, light, or nutrients, they can bleach
Bleaching is when they expel the symbiotic algae living in their tissues, causing them to turn completely white
These algae provide up to 80% of the corals food and give them their colour
Bleached corals are not dead! �Corals can survive a bleaching event, but they are under more stress and are subject to mortality

Photo credit: The Ocean Agency

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NOAA

What is coral bleaching?

Source

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Currently the main cause for global coral bleaching is the increasing sea surface temperatures driven by climate change (GCRM 2020 Report)
Average sea surface temperatures are increasing at an alarming rate worldwide, and this can have serious consequences for sensitive animals like corals
The last 10 years alone have all been reported as the hottest on record

Source

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02.

WHAT IS A�GLOBAL CORAL BLEACHING EVENT

Photo credit: The Ocean Agency

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SEA SURFACE TEMPERATURE AND CORAL BLEACHING

Significant coral bleaching has been confirmed in all the ocean regions where warm-water corals live

The maps on this page show the extent of sea surface temperatures during these events.

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THE 4TH GLOBAL

CORAL BLEACHING EVENT

There have been four global coral bleaching events on record, with two occurring in the last 10 years
The current El Niño temperatures peaked as the highest on record
Some areas have reported 50-90% coral mortality due to the bleaching event

ICRI Coral Bleaching Hub

For more updates on key messages and resources, visit:

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Source

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NOAA & ICRI ANNOUNCEMENT, �15 APRIL 2024

The world is currently experiencing its fourth global coral bleaching event, according to NOAA scientists and ICRI’s network of global coral reef scientists, the second in the last 10 years.

Mass bleaching of coral reefs, since early 2023, has been confirmed in at least 53 countries, territories, and local economies, including Florida (U.S.A), the Caribbean, the Eastern Tropical Pacific (including Mexico, El Salvador, Costa Rica, Panama, and Colombia), Australia’s Great Barrier Reef, large areas of the South Pacific (including Fiji, Vanuatu, Tuvalu, Kiribati, and the Samoas), the Red Sea (including the Gulf of Aqaba), the Persian Gulf, and the Gulf of Aden.”

Sources: NOAA | ICRI

“

Photo credit: The Ocean Agency

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Photo credit: The Ocean Agency

WHAT CAN THE

DIVING AND SNORKELLING INDUSTRY DO

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IN LIGHT OF GLOBAL �CORAL BLEACHING, �WHAT CAN WE DO?

Reducing local impacts increases reef resilience, a chance for corals to recover �(read more about the research)
Global climate change and other global threats can be daunting, but focusing on local impacts is something we can do every day
Monitor coral reefs near your dive operation and report it to decision makers and NGOs
Help reefs recover from bleaching events by managing predator outbreaks and continuing to reduce our impacts

Photo credit: The Ocean Agency

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WHAT IS�REEF RESILIENCE

Reef resilience is the ability to resist and recover from disturbances
To make sure reefs stay resilient, local threats must be kept to a minimum
We can work together to reduce these impacts from marine tourism

LISTEN

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Chemical Discharge

REDUCE LOCAL IMPACTS

Be mindful of chemical pollution from a variety of sources
Choose non-toxic cleaning agents, non-toxic sunscreens, holding tanks on boats, and septic systems
No fish feeding as this can lead to increases in algal abundance
Solutions for these can be implemented easily and they will greatly reduce land-based threats to coral reefs

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REDUCE LOCAL IMPACTS

Click on images to download posters for free

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Waste Management

REDUCE LOCAL IMPACTS

Waste management when living and interacting with marine ecosystems is vital
Ensuring waste from land does not make it to the ocean is a big positive impact we can have on the marine environment
Eliminating the waste at source by not using disposable plastic can educate guests and improve reef resilience

Click on images to download posters for free

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Other Impacts

REDUCE LOCAL IMPACTS

The Green Fins Code of Conduct is designed to help marine tourism operators reduce their impacts on marine ecosystems
It is a proven method for reducing impacts discussed in this toolkit, as well as many others
There are free materials available in multiple languages to assist with this

Green Fins Action Centre

For more readily available materials, visit:

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BRIEFING YOUR GUESTS

It is always important to brief your guests about environmental best practice on all dives
Particularly during bleaching events, diver’s contact with the reef can significantly damage corals that are already weakened
Consider adding information about bleaching and why divers should be extra careful during bleaching events
Remember to explain why you are monitoring the bleaching to educate them on conservation efforts and how to get involved. The more eyes on reefs, the better!
Give busy dive and snorkel sites a rest (recommended by Reef Check Malaysia and Coral Reef Alliance)

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MONITOR THE REEFS

WHAT DOES YOUR MONITORING DATA DO?

Ground-truth predictive models, these help with international and national level management of coral reefs
Help local reef managers understand the most vulnerable and most resilient areas
Identify reef refugia; areas of reef that are more resilient to bleaching
Be part of something bigger than yourselves!

“Citizen science can fill that gap in data collection and help decision-makers in environmental conservation and management make well-informed decisions.” — Dr. Rubén Torres, Founder and President of Reef Check Dominican Republic

Coral Reef Watch - Coral Bleaching Forecast

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Monitoring Guide

Watch this training video by the Coral Reef Alliance describing the different types of monitoring.
If full surveys are not feasible for you, try taking photos of sites or individual bleached coral colonies over time with water temperature data and submit this directly to NOAA or regional partners.
Try to monitor your chosen site(s) or coral(s) every 2-weeks, or at least once a month through the bleaching event.

Video Credit: Coral Reef Alliance

Submit data here

Remember to always follow environmental best practice while in the water

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ASSIST REEF RECOVERY

Additional knowledge:

After bleaching events, corals are highly susceptible to disease and predation
While coral predators are a natural part of the ecosystem, they can become overpopulated and threaten coral reefs on a large scale
To help coral reefs recover from bleaching events consider learning how to:

Monitor coral predator populations
Identify if they are overpopulated
Manage the threat through controlled removals

Drupella research

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SHARE THIS TOOLKIT WITH YOUR NETWORK!

Share on your social media

The Reef-World Foundation leads the global implementation of the UN Environment Programme’s Green Fins initiative, which focuses on driving environmentally friendly scuba diving and snorkelling practices across the industry globally.

The Reef-World Foundation - Registered UK Charity No: 1157096 | www.reef-world.org

www.greenfins.com |

If you have any questions or feedback about this toolkit, please contact info@greenfins.net

or start a discussion on Green Fins Community Forum.

Download assets

greenfins.net/coral-bleaching

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