Reef Restoration

INTRODUCTION: REEF RESTORATION AND HISTORY

Reef restoration, according to the Great Barrier Reef foundation, involves the “rebuild [of] damaged coral reefs” in order to enhance the health of coral reef ecosystems. This rebuild of coral reefs involves methods such as reseeding and regrowing, which involve “planting” corals to regenerate reefs that have been decimated from natural and anthropogenic threats. This is important because reefs are currently being harmed by a variety of threats, including climate change. In particular, restoring reefs involves having reefs that are more resilient against warming temperatures and ocean acidification, two major consequences of climate change that most directly harm coral reefs.

Reef restoration initially was focused on how to protect coral reefs that were affected by ships moving through oceans. This form of reef restoration was seen more through a “reactive” perspective, only focusing on reefs that were most vulnerable to being struck by ships. However, over time, it became more obvious that reefs in general were being threatened by many different threats - direct and indirect - including climate change. This made it critical to implement projects that would safeguard many different reefs. Furthermore, in the modern world, organizations and government agencies like NOAA have been able to use many different techniques to restore coral reefs, such as undersea dwellings, SCUBA diving, submersible vehicles, coral nurseries, and satellites (NOAA 2025).

Other species of coral, such as this Montastrea species, have been used in propagating corals in Florida. (/static/images/restoration_articleimage1.png) (/static/images/restoration_articleimage1.png) Innovations such as SCUBA diving allow researchers to go underwater to restore damaged reefs. From: (https://www.noaa.gov/heritage/stories/from-threat-to-threatened-brief-history-of-coral-reef-research)

REEF RESTORATION METHODS

CASE STUDIES

INDONESIA

In Indonesia, there are many ongoing reef restoration projects to help rebuild reefs that have been severely impacted by climate change and other anthropogenic causes.These restoration efforts employ a variety of different restoration methods in combination with related governmental policy. However, these efforts are disjointed, and are rarely monitored after initial implementation.

Indonesia’s recent approach to restoring reefs has come from a collaborative, community-based standpoint. The country’s government has enacted multiple laws and policies that reflect this agenda. Essentially, Indonesia’s government encourages and allows anyone and everyone, be that individuals, groups, communities, or even local governments, to actively participate in reef restoration (Razak et. al 2022). This has resulted in reef restoration projects popping up all over the country, and a significant amount of progress being made. However, the Indonesian government does not currently have a broader, more widespread plan or agenda for long term reef restoration across the country.

Since reef restoration in Indonesia is coming from so many different groups and actors, there are many different methods in play. Since 1990, there have been upwards of 500 reef restoration projects in Indonesia, all of which employ a myriad of different strategies and tactics, the most common of which include some combination of transplantation and artificial reef structures. Across all these restoration projects and efforts, nearly one million individual hard coral fragments have been planted, and over one hundred thousand artificial reef units have been installed (Razak et. al 2022).

Although there has been a significant initial restoration effort in Indonesia, reef monitoring after restoration has been lacking. In fact, only around 16% of the 500+ restoration projects in Indonesia incorporated some kind of monitoring program (Razak et. al 2022). This means that while there may be a lot of transplantation and artificial reef construction occurring, the long-term effects of these efforts are largely unknown. In addition to the lack of monitoring, these restoration efforts are largely independent of one another, and therefore are not as connected, coordinated, and efficient as they could be if they were part of a more centralized initiative.

Overall, reef restoration is still an ongoing task in Indonesia, and there are thousands of people working to accomplish it every day. There is a large variety in the methodology of reef restoration projects, meaning these efforts have varying levels of success, but together they may have a chance at preventing ecological disaster from occurring in the reefs of Indonesia.

ZANZIBAR

Chumbe Island, located off the coast of Zanzibar, Tanzania, is home to one of the most diverse reefs in East Africa and holds incredible biodiversity value for East African coastal ecosystems. However, the reef was suffering due to overfishing and harmful fishing methods such as dynamite fishing and smashing corals. Rapid population growth and mass tourism further contributed to the pressure on the reef. Unfortunately, the situation was exacerbated by Zanzibar’s lack of marine governance and enforcement as well as a lack of alternative income opportunities for local residents (Reef Resilience Network 2022).

Seeking to combat these trends, Sybille Riedmiller led the founding of Chumbe Island Coral Park (CHICOP) in 1992. The Park protects Chumbe Island and the surrounding marine habitat. The goal of CHICOP was to create a marine park where money from tourism operations could be reinvested towards conservation and environmental education, as well as employ local fishermen as park rangers where they can educate fellow fishermen about the benefits of a protected reef area. Today, activities such as fishing, anchoring, and specimen collecting are completely prohibited. Recreational and tourism activities like snorkeling and underwater photography are still permitted. CHICOP aims to sustainably manage its biodiversity and conservation operations, serve as a model for effective ecotourism and MPA management, and provide a platform for environmental education for Zanzibar residents (Reef Resilience Network 2022).

CHICOP has been incredibly successful as an ecotourism destination and conservation project. 95% of the Park’s total staff are Zanzibar locals, and protection of CHICOP’s reef has restocked previously overfished reefs adjacent to the MPA - demonstrating the economic benefit to the local people. Poaching and trespassing have decreased to an average of 6 incidents per year in 2016, as compared to nearly 170 per year when CHICOP was established. CHICOP has also been very beneficial for environmental education in coral reef ecology and conservation for people throughout Zanzibar and Tanzania - who often have very little knowledge of the importance of reefs. The Park offers one-day field trips to local students and teachers to provide hands-on experience in marine biology and conservation. As a result, the program has boomed in popularity, raised awareness about environmental issues among students, and even inspired knock-on effects in the region such as the establishment of local environmental clubs and conservation projects (Reef Resilience Network 2022).

Perhaps most importantly, CHICOP has had a phenomenal effect on the health of the reef within its boundaries. When high densities of crown-of-thorns sea stars (COTS) were observed in the reef, CHICOP management enacted a removal program carried out by park rangers who manually remove COTS within the reef. 4,076 COTS have been removed since 2004. Additionally, Chumbe’s corals have been exceptionally resilient to large-scale bleaching events. During the 2016 El Nino event, mass coral bleaching occurred globally - and Chumbe was no exception. 80% of the hard corals within CHICOP temporarily bleached, but due to the absence of any other stressors (like fishing or destructive activities) more than 70% of hard corals on the reef recovered and new coral larvae recruitment was observed directly after the event. Subsequent global and regional bleaching events have not had a significant impact on CHICOP’s corals (Reef Resilience Network 2022). Clearly, CHICOP’s conservation and restoration strategies are working to improve coral health.

CHICOP’s success points to the effectiveness and viability of private MPA management as a method for reef restoration. Private management has a strong incentive to achieve tangible conservation goals while maintaining positive relations with the local community and being cost-effective. When done correctly, this private management benefits local communities economically and results in better resource management and conservation than many other methods. Providing environmental education is also extremely important (especially within the developing world), as it enhances understanding of issues facing reefs within local populations and government authorities that may not have otherwise considered them or taken steps to protect reefs (Reef Resilience Network 2022). While it may not be a method traditionally thought of within the field of reef restoration, CHICOP’s style of private MPA management and environmental education shows a lot of promise and inspires hope for the future of coral reefs.

FLORIDA

The reef ecosystems off the coast of Florida have experienced a number of different threats, such as diseases (especially Stony Coral Tissue Loss Disease, or SCTLD), tropical cyclones, and negative externalities of climate change (specifically bleaching). This has caused some species to be listed as threatened, including a few Acropora species. To make matters worse, young corals are also experiencing increased difficulty in being able to recover from these kinds of threats, especially SCTLD (Reef Resilience Network 2022).

However, in 2000, Ken Nedimyer and his daughter both initiated a funded pilot study that involved creating adult coral structures using parts of existing coral. This study ended up being successful, and they were able to subsequently obtain more funding from a variety of public and private organizations to propagate more coral reefs through this method throughout the Florida coast, helping to construct coral nurseries in the Florida reefs. Specifically, he used coral parts from hard Acropora coral species, which were ideal to produce coral nurseries in areas that experienced minimal anthropogenic impacts because they were most easily capable of sprouting into mature reefs (Reef Resilience Network 2022).

Not only has this technique been used to restore the species diversity of the harmed reefs, but it also aided in the improvement of the genetic diversity of these reefs when genetic technologies became involved in these projects. However, only propagating Acropora species was insufficient for reef restoration of Florida reefs, and as a result, scientists began propagating remnants of other coral species, including species found in the Montastrea, Orbicella, and Pseudodiploria groups (Reef Resilience Network 2022).

(/static/images/restoration_articleimage2.png) (/static/images/restoration_articleimage2.png) Other species of coral, such as this Montastrea species, have been used in propagating corals in Florida. From: florida-cological-restoration (https://reefresilience.org/case-studies/florida-ecological-restoration/)

Overall, the results have been successful, as thousands of corals in Florida have been restored using this technique. It also led to the development of a guide to restore other corals, specifically Acropora corals, in other places such as the Caribbean, known as the “Caribbean Acropora Restoration Guide: Best Practices for Propagation and Population Enhancement”. Other initiatives for restoring Florida’s reefs have also come about from these efforts, including “Mission: Iconic Reefs” (Reef Resilience Network 2022).

DISCUSSION

Coral reefs are some of the most biodiverse and have the most productive ecosystems. Climate change has greatly affected them with the ocean temperatures rising and damaging all of the aquatic ecosystems they support things such as pollution, overfishing and many other threats that contribute to rapid decline within these ecosystems. This is why reef restoration needs to become not only a necessity, but a moral obligation. Restoration methods used to be on a small scale but are now becoming a rapidly expanding field that is tied to sustainability, equity, and survival.

In the most basic form, restoration is the act of helping a degraded ecosystem recover. In the case of coral reefs, restoration could look like coral gardening, transplanting corals, putting in artificial structures,and new techniques such as micro fragmentation and larval propagation to help stimulate a natural recovery process or give reef systems resilience that may not recover without assistance. Historically, reef restoration was viewed as a last resort. It was just a means to help reefs in areas that were degraded. The narrative is changing and it is becoming less of an option due to everything that is happening.

There is a business case for reef restoration. Coral reefs support the lives of millions around the world. It was mainly for those that live on islands or along the coast. The tourism, recreation, and fisheries industries rely on them heavily. They need reefs to be healthy or all of these communities will have economic losses. The restoration does not only benefit these industries but it also diversifies the local economy. They build capacity, training individuals to be coral gardeners, snorkel guides, and reef monitors, this creates jobs and leads to communities investing into environmental protection.

FUTURE IDEAS

Areas for further discussion could include the economics of reef restoration, the ecological effects of reef restoration, and the future of reef restoration.

REFERENCES

National Oceanic and Atmospheric Administration. (2025). From threat to threatened: A brief history of coral reef research. (https://www.noaa.gov/heritage/stories/from-threat-to-threatened-brief-history-of-coral-reef-researchLinks to an external site.)

Razak, T. B., Boström-Einarsson, L., Alisa, C. A., Vida, R. T., & Lamont, T. A. C. (2022). Coral Reef Restoration in Indonesia: A review of policies and projects. Marine Policy, 137. (https://doi.org/10.1016/j.marpol.2021.104940Links to an external site.)

Reef Resilience Network. (2022). Florida - ecological restoration. The Nature Conservancy. (https://reefresilience.org/case-studies/florida-ecological-restoration/Links to an external site.)

Reef Resilience Network. (2022). Tanzania—MPA management. The Nature Conservancy. (https://reefresilience.org/case-studies/tanzania-mpa-management/Links to an external site.)

What is reef restoration. (2023). Great Barrier Reef Foundation. ​ (https://www.barrierreef.org/news/explainers/what-is-reef-restorationLinks to an external site.)