Phestilla nudibranchs

Phestilla nudibranchs are tiny sea slugs that feed exclusively on hard corals. They damage corals by releasing enzymes that dissolve the coral's protective skeleton, allowing them to consume the living tissue beneath. They also reproduce quickly, laying egg masses directly on corals, which can cause infestations to spread rapidly if left untreated.

Most bristle worms are beneficial scavengers that help keep reef ecosystems healthy by consuming waste and recycling nutrients. However, certain predatory species, including fireworms found in Hawaiʻi, can become serious coral pests. These worms feed directly on coral tissue, reproduce quickly, and can cause significant damage to coral fragments if left unchecked.

Coral Reef Restoration

Rebuilding Maui’s
Living Infrastructure

To the people of Hawai‘i, ʻākoʻakoʻa (coral reefs) are central to cultural identity and form the very foundation of island biodiversity and coastal protection. These reefs are regarded as ancient, living legacies that embody a shared kuleana (responsibility) for the health of our surrounding waters.

Hawai‘i’s coral reefs are the foundation of our marine biodiversity, providing habitat for nearly 25% of all marine life despite occupying only 1% of the ocean floor. They are essential for protecting our coastlines and infrastructure, sustaining local food sources, and fueling Hawaiʻi's tourism economy. However, our reefs face unprecedented decline due to land-based sources of pollution, overfishing, devastating vessel groundings, and rising sea temperatures.

One of the most prominent global threats to coral reefs is coral bleaching, which is a stress response to increased ocean temperatures. When a coral bleaches, its symbiotic relationship with zooxanthellae algae—which gives coral its color—breaks down, causing the algae to be expelled from the host. This leaves the coral colorless and increasingly vulnerable to disease and starvation. To ensure our coral reefs survive for future generations, we are shifting from acute crisis response to long-term resilience strategies.

Our Approach

The Science of Reef Resilience

Coral reefs will not recover on their own timeline. Meaningful restoration requires infrastructure, precision, and sustained commitment—which is why we operate Maui's only land-based coral nursery. Our "Response to Reef" model integrates Indigenous ecological knowledge with science-based propagation, guiding every coral from collection to outplanting to long-term monitoring.

Outplanting 1,000 corals costs approximately $200,000. The six steps below show exactly where that investment goes — and why each one matters.

Step 1: Collect Corals of Opportunity

Corals of opportunity (COO) are colonies that have been naturally dislodged by storms, turbulence and predation, or by human disturbances and would be unlikely to survive without intervention. Under strict state permits, our team collects a set number of COO’s for our restoration process.

Step 2: Acclimation & Thermal Tolerance Testing

Inside our nursery, each rescued colony undergoes thermal tolerance testing to evaluate their relative resilience to rising ocean temperatures. Over the course of several weeks, fragments of each colony are experimentally exposed to elevated temperatures and their health is evaluated using a numerical bleaching score. The more pale or bleached a coral becomes, the lower the coral is scored to reflect its thermal response. This technique identifies corals predisposed to higher thermal tolerance to ensure the highest rates of survival.

Step 4: Nursery Monitoring & Husbandry

Our dedicated team of husbandry staff and volunteers care for our corals during the growth phase. This involves daily cleaning, feeding, health inspections for signs of stress, and water quality monitoring. We also utilize aquacultured native Hawaiian collector urchins and yellow tangs to manage algae growth, ensuring a healthy environment for all stages of coral development.

Step 5: Strategic Outplanting

Once corals reach the desired size, they are outplanted back onto their reef of origin. Our outplanting strategy is informed by the thermal tolerance experiments conducted in the lab. For example, corals found to be more thermally tolerant are strategically outplanted in shallower areas, whereas those less tolerant to heat are outplanted at greater depths. This approach builds widespread, long-term genetic diversity of our reefs while restoring the living infrastructure the reef naturally provides.

Step 6: Monitoring & Data Collection

Our monitoring work continues long after outplanting. We assess coral health, confirm survivorship , and evaluate attachment success to ensure plugs are holding and corals remain secured. We also look for natural skirting, where new coral growth spreads from the plug onto surrounding reef substrate, note any sediment smothering and document bleaching events when elevated water temperatures are recorded. Photogrammetry is also used to create 3D images, helping build a long-term picture of reef vitality and restoration success.

Step 2: Acclimation & Thermal Tolerance Testing

Inside our nursery, each rescued colony undergoes thermal tolerance testing to evaluate their relative resilience to rising ocean temperatures. Over the course of several weeks, fragments of each colony are experimentally exposed to elevated temperatures and their health is evaluated using a numerical bleaching score. The more pale or bleached a coral becomes, the lower the coral is scored to reflect its thermal response. This technique identifies corals predisposed to higher thermal tolerance to ensure the highest rates of survival.

Step 4: Nursery Monitoring & Husbandry

Our dedicated team of husbandry staff and volunteers care for our corals during the growth phase. This involves daily cleaning, feeding, health inspections for signs of stress, and water quality monitoring. We also utilize aquacultured native Hawaiian collector urchins and yellow tangs to manage algae growth, ensuring a healthy environment for all stages of coral development.

Step 5: Strategic Outplanting

Once corals reach the desired size, they are outplanted back onto their reef of origin. Our outplanting strategy is informed by the thermal tolerance experiments conducted in the lab. For example, corals found to be more thermally tolerant are strategically outplanted in shallower areas, whereas those less tolerant to heat are outplanted at greater depths. This approach builds widespread, long-term genetic diversity of our reefs while restoring the living infrastructure the reef naturally provides.

Step 6: Monitoring & Data Collection

Our monitoring work continues long after outplanting. We assess coral health, confirm survivorship , and evaluate attachment success to ensure plugs are holding and corals remain secured. We also look for natural skirting, where new coral growth spreads from the plug onto surrounding reef substrate, note any sediment smothering and document bleaching events when elevated water temperatures are recorded. Photogrammetry is also used to create 3D images, helping build a long-term picture of reef vitality and restoration success.

Step 2: Acclimation & Thermal Tolerance Testing

Inside our nursery, each rescued colony undergoes thermal tolerance testing to evaluate their relative resilience to rising ocean temperatures. Over the course of several weeks, fragments of each colony are experimentally exposed to elevated temperatures and their health is evaluated using a numerical bleaching score. The more pale or bleached a coral becomes, the lower the coral is scored to reflect its thermal response. This technique identifies corals predisposed to higher thermal tolerance to ensure the highest rates of survival.

Step 4: Nursery Monitoring & Husbandry

Our dedicated team of husbandry staff and volunteers care for our corals during the growth phase. This involves daily cleaning, feeding, health inspections for signs of stress, and water quality monitoring. We also utilize aquacultured native Hawaiian collector urchins and yellow tangs to manage algae growth, ensuring a healthy environment for all stages of coral development.

Step 5: Strategic Outplanting

Once corals reach the desired size, they are outplanted back onto their reef of origin. Our outplanting strategy is informed by the thermal tolerance experiments conducted in the lab. For example, corals found to be more thermally tolerant are strategically outplanted in shallower areas, whereas those less tolerant to heat are outplanted at greater depths. This approach builds widespread, long-term genetic diversity of our reefs while restoring the living infrastructure the reef naturally provides.

Step 6: Monitoring & Data Collection

Our monitoring work continues long after outplanting. We assess coral health, confirm survivorship , and evaluate attachment success to ensure plugs are holding and corals remain secured. We also look for natural skirting, where new coral growth spreads from the plug onto surrounding reef substrate, note any sediment smothering and document bleaching events when elevated water temperatures are recorded. Photogrammetry is also used to create 3D images, helping build a long-term picture of reef vitality and restoration success.

Step 2: Acclimation & Thermal Tolerance Testing

Inside our nursery, each rescued colony undergoes thermal tolerance testing to evaluate their relative resilience to rising ocean temperatures. Over the course of several weeks, fragments of each colony are experimentally exposed to elevated temperatures and their health is evaluated using a numerical bleaching score. The more pale or bleached a coral becomes, the lower the coral is scored to reflect its thermal response. This technique identifies corals predisposed to higher thermal tolerance to ensure the highest rates of survival.

Step 4: Nursery Monitoring & Husbandry

Our dedicated team of husbandry staff and volunteers care for our corals during the growth phase. This involves daily cleaning, feeding, health inspections for signs of stress, and water quality monitoring. We also utilize aquacultured native Hawaiian collector urchins and yellow tangs to manage algae growth, ensuring a healthy environment for all stages of coral development.

Step 5: Strategic Outplanting

Once corals reach the desired size, they are outplanted back onto their reef of origin. Our outplanting strategy is informed by the thermal tolerance experiments conducted in the lab. For example, corals found to be more thermally tolerant are strategically outplanted in shallower areas, whereas those less tolerant to heat are outplanted at greater depths. This approach builds widespread, long-term genetic diversity of our reefs while restoring the living infrastructure the reef naturally provides.

Step 6: Monitoring & Data Collection

Our monitoring work continues long after outplanting. We assess coral health, confirm survivorship , and evaluate attachment success to ensure plugs are holding and corals remain secured. We also look for natural skirting, where new coral growth spreads from the plug onto surrounding reef substrate, note any sediment smothering and document bleaching events when elevated water temperatures are recorded. Photogrammetry is also used to create 3D images, helping build a long-term picture of reef vitality and restoration success.

Step 2: Acclimation & Thermal Tolerance Testing

Inside our nursery, each rescued colony undergoes thermal tolerance testing to evaluate their relative resilience to rising ocean temperatures. Over the course of several weeks, fragments of each colony are experimentally exposed to elevated temperatures and their health is evaluated using a numerical bleaching score. The more pale or bleached a coral becomes, the lower the coral is scored to reflect its thermal response. This technique identifies corals predisposed to higher thermal tolerance to ensure the highest rates of survival.

Step 4: Nursery Monitoring & Husbandry

Our dedicated team of husbandry staff and volunteers care for our corals during the growth phase. This involves daily cleaning, feeding, health inspections for signs of stress, and water quality monitoring. We also utilize aquacultured native Hawaiian collector urchins and yellow tangs to manage algae growth, ensuring a healthy environment for all stages of coral development.

Step 5: Strategic Outplanting

Once corals reach the desired size, they are outplanted back onto their reef of origin. Our outplanting strategy is informed by the thermal tolerance experiments conducted in the lab. For example, corals found to be more thermally tolerant are strategically outplanted in shallower areas, whereas those less tolerant to heat are outplanted at greater depths. This approach builds widespread, long-term genetic diversity of our reefs while restoring the living infrastructure the reef naturally provides.

Step 6: Monitoring & Data Collection

Our monitoring work continues long after outplanting. We assess coral health, confirm survivorship , and evaluate attachment success to ensure plugs are holding and corals remain secured. We also look for natural skirting, where new coral growth spreads from the plug onto surrounding reef substrate, note any sediment smothering and document bleaching events when elevated water temperatures are recorded. Photogrammetry is also used to create 3D images, helping build a long-term picture of reef vitality and restoration success.

The technical process of micro-fragmenting—cutting a healthy colony into smaller pieces—triggers a coral's natural healing response. This accelerates tissue growth by up to 25X, stimulating the coral to grow much faster than it would in the wild.

Did you know?

Current Projects

Olowalu Reef

Honolua Bay

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Z-Blocks Initiative

Common Coral Threats

Like all living organisms, corals are vulnerable to pests and disease. In both the wild and coral nurseries, threats such as predatory invertebrates, invasive species, harmful algae, bacteria, and other pathogens can damage coral tissue, slow growth, and reduce survival.

Corals become especially susceptible when they are under stress. Poor water quality, sedimentation, pollution, rising ocean temperatures, ocean acidification, and physical damage can weaken a coral's natural defenses, making it easier for pests and diseases to take hold. As reefs decline, the impacts ripple throughout the ecosystem, affecting the fish and other marine life that depend on healthy coral habitat.

Protecting corals requires early detection, ongoing monitoring, and effective management. By understanding the most common pests and diseases, researchers and conservationists can respond quickly to protect coral nurseries and improve the success of reef restoration efforts.

Aiptasia are small sea anemones that can become a serious threat in coral nurseries. Although they may appear harmless, they reproduce rapidly and spread quickly throughout closed systems. Their powerful sting can injure or kill coral tissue, while competing with corals for space and light. Because of their fast growth and resilience, early detection and removal are essential to protect vulnerable corals.

White Band Disease (WBD) primarily affects Acropora corals, including staghorn and elkhorn species. It causes living coral tissue to peel away from the skeleton, leaving behind a distinct white band of exposed coral. While the exact cause is still being studied, the disease is often associated with environmental stress, such as coral bleaching, and can spread rapidly through vulnerable coral populations.

White Plague (WP) is a rapidly progressing disease that affects many species of hard corals, causing living tissue to die and slough away, exposing the bright white skeleton beneath. Although its symptoms are similar to White Band Disease, White Plague does not affect Acropora corals. Researchers have identified three forms of White Plague, which differ in how quickly they spread and the severity of the damage they cause. While one form has been linked to the bacterium Aurantimonas coralicida, the causes of White Plague are still an active area of research.

Coral growth anomalies (GAs), sometimes called coral tumors or neoplasms, are abnormal growths that have been documented in several coral species, most notably most notably Acropora and Porites. They appear as raised, pale, irregular masses that disrupt the coral's normal structure and growth. Although the exact cause remains unknown, affected corals often grow more slowly, have reduced access to nutrients, and are more vulnerable to predators and other environmental stressors.

Algal infestations occur when fast-growing algae overtake corals, blocking sunlight, competing for space, and preventing healthy growth. They often develop after corals have been weakened by disease, bleaching, or physical damage. In Hawaiʻi, several invasive algae species have spread beyond their original introduction sites and can outcompete native marine life, threatening the health of coral reefs.

Crown-of-Thorns Starfish (COTS) are large, venomous sea stars that feed on living hard corals. They consume coral by everting their stomach over the coral's surface, digesting the tissue and leaving behind a white coral skeleton. While healthy reefs can support small numbers of COTS, population outbreaks can devastate coral reefs by rapidly consuming large areas of living coral. Because a single female can produce millions of eggs each spawning season, outbreaks can spread quickly, making early detection and management essential to protecting vulnerable reefs.

Coral bleaching is a stress response that occurs when corals lose the microscopic algae living within their tissues. These algae provide up to 90% of a coral's energy and give corals much of their color. When corals become stressed, most commonly from unusually warm ocean temperatures, they expel the algae, causing the coral to appear bright white or, in some species, pale shades of pink, blue, or yellow. Although bleached corals are still alive, they are weakened and more vulnerable to disease, predation, and death. If environmental conditions improve quickly, corals can regain their algae and recover. However, prolonged or repeated bleaching events can result in widespread coral loss, threatening the health of reef ecosystems around the world.

Coral Conservation in Action

Every coral in this gallery represents countless hours of dedication, from collection and propagation to outplanting and long-term monitoring. It costs approximately $200,000 to collect, grow, and restore 1,000 corals to Hawaiʻi's reefs, making this work possible only through the generosity of our donors, supporters, and coral adopters. We are also deeply grateful to the incredible volunteers who contribute their time and passion to coral collection, nursery husbandry, outplanting, Hana Pūkoʻa community restoration events, education, and outreach. Together, we are restoring reefs and helping ensure a healthier future for Hawaiʻi's marine ecosystems.

Coral Collection

Support & Stewardship

Every reef we rebuild is powered by the collective strength of our community. While large-scale initiatives are the goal of our work, every contribution directly sustains the daily technical operations of Maui’s only land-based coral nursery. You can directly fuel coral restoration through the following professional pathways:

MI Coral Project Nahoia_Kai_Productios Small Size For Social-38.jpg

Support Coral Restoration

Your donation helps support every coral of opportunity that is given a second chance to rebuild our reefs.

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Sponsor A Restoration Project

Your business can demonstrate verifiable ESG (Environmental, Social, and Governance) impact by underwriting large-scale restoration efforts. Perks include access to corporate experiences, behind-the-scenes tours, and more.

Get Involved

Join a Hana Pūko'a Event

Immerse yourself in the work of restoration. Follow us on social media and sign up for our newsletter to be notified of upcoming community stewardship dates, volunteer opportunities, and a chance to make a difference for our reefs.

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Symbolically Adopt a Coral

Provide immediate support for the daily care and specialized supplies required for the fragments currently in our nursery. Choose from four corals, or select our “save the reef” package for a bigger impact.

Adopt Now

Coral Reef Restoration

Rebuilding Maui’s
Living Infrastructure

Our Approach

The Science of Reef Resilience

The technical process of micro-fragmenting—cutting a healthy colony into smaller pieces—triggers a coral's natural healing response. This accelerates tissue growth by up to 25X, stimulating the coral to grow much faster than it would in the wild.

Did you know?

Current Projects

Olowalu Reef

Honolua Bay

Z-Blocks Initiative

Common Coral Threats

Phestilla nudibranchs

Aiptasia

Bristle Worms

White Band Disease

White Plague

Coral growth anomalies

Algal Infestations

Crown-of-Thorns Starfish

Coral Bleaching

Coral Conservation in Action

Support & Stewardship

Support Coral Restoration

Sponsor A Restoration Project

Join a Hana Pūko'a Event

Symbolically Adopt a Coral

Report a Sick or Injured Turtle

808-286-2549

Report a Monk Seal Sighting

808-292-2372

Stay Connected

Subscribe to Our Newsletter

Coral Reef Restoration

Rebuilding Maui’s Living Infrastructure

Our Approach

The Science of Reef Resilience

The technical process of micro-fragmenting—cutting a healthy colony into smaller pieces—triggers a coral's natural healing response. This accelerates tissue growth by up to 25X, stimulating the coral to grow much faster than it would in the wild.

Did you know?

Current Projects

Olowalu Reef

Honolua Bay

Z-Blocks Initiative

Common Coral Threats

Phestilla nudibranchs

Aiptasia

Bristle Worms

White Band Disease

White Plague

Coral growth anomalies

Algal Infestations

Crown-of-Thorns Starfish

Coral Bleaching

Coral Conservation in Action

Support & Stewardship

Support Coral Restoration

Sponsor A Restoration Project

Join a Hana Pūko'a Event

Symbolically Adopt a Coral

Report a Sick or Injured Turtle

808-286-2549

Report a Monk Seal Sighting

808-292-2372

Stay Connected

Subscribe to Our Newsletter

Rebuilding Maui’s
Living Infrastructure