Recovery Potential Of The World’s Coral Reef Fishes

Fishing is the primary source of reduced reef function globally. Marine reserves are a critical tool to help fish populations recover, however, there are no benchmarks to determine if the protection is effective, or whether a reserve has recovered enough to be fished again. By studying remote and marine protected areas, they estimate how many fish would be on a coral reef without fishing, and how long it should take newly protected areas to recover. This helps to assess the impact of reef fisheries, and make informed management decisions that include timeframes for recovery.

Specifically, this paper presents the first empirical estimate of coral reef fisheries recovery potential, compiling data from 832 coral reefs across 64 localities (countries and territories. The authors estimate the expected density of reef fish on unfished reefs; quantify the rate of reef fish biomass recovery in well-enforced marine reserves; characterize the state of reef fish communities within fished and managed areas; predict the time required to recover biomass and ecosystem functions; and explore the potential returns in biomass and function using off-reserve management throughout the broader reefscape. The research team studied the fish biomass on coral reefs around the world and discovered that near-pristine reefs contain 1,000 kg of fish per hectare. Using this figure as a benchmark, they found that 83% of fished reefs have lost more than half of their fish biomass (volume of fish).

The authors discuss how reef fish populations were better off when fishing activities were restricted (e.g., including limitations on the species that could be caught, the gears that could be used, and controlled access rights). The authors determined that once protected, fished reefs take about 35 years to recover, while heavily depleted reefs take almost 60 years. Although the influence of marine reserves can be detected within several years, this global analysis demonstrated that full recovery of reef fish biomass takes decades to achieve. Importantly, this suggests that most marine reserves implemented in the past 10–20 years, will require many more years to achieve their recovery potential. This has important implications for managing expectations of MPAs and also reinforces the need for continued, effective protection and consideration of other viable management options. The authors also found that in reef areas where MPAs cannot be implemented, a range of fisheries can have substantial effects on fish functional groups that support important reef processes.

Author: MacNeil, M.A., N.A.J. Graham, J.E. Cinner, S.K. Wilson, I.D. Williams, J. Maina, S. Newman, A.M. Friedlander, S. Jupiter, N.V.C. Polunin, and T.R. McClanahan
Year: 2015
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Nature 520: 341-344. doi:10.1038/nature14358

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Biogeography And Change Among Regional Coral Communities Across The Western Indian Ocean

Following the major 1998 coral bleaching event between 2004 and 2011, 291 coral sites from 11 Western Indian Ocean (WIO) countries were surveyed to evaluate regional biogeographic patterns of coral communities along latitudinal gradients and in relation to biogeography and fisheries management. Coral reef abundance, biodiversity, and susceptibility to bleaching were assessed during that period to develop an extensive database on coral reef communities and researchers aimed to evaluate possible impacts such as fishing and fishing closures on reef patterns and status. Patterns show that coral communities are influenced by large-scale interactions between biogeographic factors and temperature abnormalities but not so much by fisheries management. All coral reefs in the WIO are experiencing climate change and coral bleaching since the early 1980s, but at variable rates, timing and scale depending on the geography. The region was characterized by a complexity of a large number of significant interactions among variables tested. The northern Mozambique Channel demonstrated the strongest signs of resilience to climate disturbances.

Author: McClanahan, T.R., M. Atewberhan, E.S. Darling, N.A.J. Graham, and N.A. Muthiga
Year: 2014
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PLoS ONE 9(4): e93385. doi: 10.1371/journal.pone.0093385

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Relationship Between Phylogeny And Immunity Suggests Older Caribbean Coral Lineages Are More Resistant to Disease

This study looked at the evolutionary importance of coral immune traits, which are related to phylogeny in other organisms. 140 different fragments from healthy coral colonies were sampled, representing 14 of the most common Caribbean hard corals (20% of regional hard coral diversity) to test for the presence of a phylogenetic signal in immune traits. Published disease data was compiled to determine levels of immune-competence by a number of diseases affecting each species and its mean prevalence in the population. Results showed that disease resistance varies significantly among coral taxa for some immune-related process; species with older lineages demonstrated less disease prevalence compared to modern linages of corals. Older coral lineages (including Porites, Siderastrea radians and Meandrinidae) may be more resilient to conditions of the present and future.

Author: Pinzon, C J.H., J. Beach-Letendre, E. Weil, and L.D. Mydlarz
Year: 2014
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PLoS ONE 9(8): e104787. doi: 10.1371/journal.pone.0104787

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New and improved Network Forum

The Reef Resilience Network has launched a new and improved online discussion forum!

Now part of the Reef Resilience website, this interactive online community is a place where coral reef managers and practitioners from around the world can connect and share with others to better manage marine resources.

If you work to protect, manage, or promote coral reefs please join the conversation:

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New Reef Resilience Online Course Launched

The new online course Advanced Studies in Coral Reef Resilience is designed to provide coral reef managers and practitioners in-depth guidance on managing for resilience. This free course incorporates new science, case studies, and management practices described in the Reef Resilience Toolkit.

The course includes six modules that discuss local and global stressors affecting coral reefs, guidance for identifying coral reef resilience indicators, design principles for resilient MPA networks, methods for implementing resilience assessments, and important communication tools for managers. Course participants can choose to complete any or all lessons within course modules. Read more.

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U.S. Virgin Islands – Resilience Assessment

Assessing the Relative Resilience of the Coral Reefs of St. Croix, U.S. Virgin Islands 

St. Croix, U.S. Virgin Islands (USVI)

The Challenge
Coral reefs have always been dynamic habitats in which episodic disturbances occur and set the reef growth clock back, followed by periods in which the system recovers. Under these conditions coral reefs have evolved to be resilient habitats – they can recover and maintain ecosystem function after disturbances – but this natural resilience of reefs is now being undermined. Reefs face unprecedented pressures so managers and conservationists have to support and build resilience when and where possible. As a conceptual framework, resilience has been hugely popular with conservationists but ‘operationalizing’ resilience in a management setting has been difficult. Managers can reduce stress, support recovery processes, and educate and raise awareness, but need information that helps to support these actions. This case study describes how assessments of relative resilience can be used to target and tailor management actions.

This is one of the first large-scale assessments of relative resilience to use a short-list of indicators from McClanahan et al. (2012) and follows some of the guidance provided by Maynard and Mcleod (2012). The output of the analysis is an assessment of spatial variation in relative resilience (high, medium or low) in combination with an assessment of relative levels of anthropogenic stress (high, medium or low). Managers and conservationists can use the analysis outputs to support efforts to achieve conservation outcomes, like planning marine protected area networks, targeting actions to reduce stress, and educating and engaging with stakeholders and community members. In this project in the U.S. Virgin Islands (USVI), the project leaders hoped to use the resilience assessment to meet the following objectives:

  1. Identify sites with high resilience that are not currently inside marine protected areas (MPAs).
  2. Assess threats at sites with high and low resilience to target conservation effort.
  3. Develop materials to aid in educating and engaging about the importance of Buck Island and east end MPAs.
  4. Prioritize sites for the transplantation of nursery-grown corals.

Actions Taken
The process used to complete the analysis is the same process explained in the Resilience Analysis Tutorial (pdf). Project leaders and the TNC Resilience Committee for USVI decided which resilience indicators to include in the analysis through a consultative process. Project leaders developed a spreadsheet containing all 30 of the resilience indicators described in the McClanahan et al. (2012) review. The case was made to the Committee that indicators not in the top 20 for perceived importance and strength of evidence should be excluded. This first suggestion was agreed upon; the rationale being that each additional indicator included dilutes the relative importance of each of the other indicators. In other words, a shorter list of indicators that are important to resistance properties and resilience processes is better than a longer list that includes weak indicators. The remaining indicators were then classified into three tiers based on data availability and perceived importance to resistance and resilience in USVI. The final indicators used were: resistant species, coral diversity, herbivore biomass, macroalgae cover, coral cover, temperature variability and coral disease. The anthropogenic stressors examined are fishing pressure and coastal development.

The data were collected and compiled via a combination of fieldwork and desktop analysis undertaken under the Territorial and National Coral Reef Monitoring Programs (TCRMP and NCRMP) by staff from The Nature Conservancy (TNC), the National Oceanic and Atmospheric Administration’s Coral Reef Conservation Program (NOAA CRCP), Department of Planning and Natural Resources Division of Fish and Wildlife (DPRN-DFW), and NOAA’s National Centers for Coastal Ocean Science Biogeography Branch or by this report’s authors. A relative resilience score is calculated as follows. For all 7 resilience indicators, the scores for all sites (n=267) are ‘anchored’ to the maximum score by dividing the value for each site for the indicator by the maximum value among all sites. Anchoring values produces a score for each site on a standardized 0-1 scale, which expresses the value for each site relative (as a percentage) to the maximum value. Before anchored scores for all indicators can be averaged, the anchored scores for macroalgae and coral disease are subtracted from 1, which ensures the standardized 0-1 scale is uni-directional in that a high score is always a good score. The scores are then averaged to produce the resilience score and then these scores are also anchored to the maximum score to produce a final resilience score that expresses the ‘assessed resilience’ as relative to the maximum resilience score. The same approach is used for the proxies of anthropogenic stress, which are kept separate to the resilience scores. The values are anchored for all sites for each proxy to the maximum value and then the values are averaged and re-anchored to produce the final stress score. For stress, high scores mean high stress. For both resilience and anthropogenic stress, a high, medium and low scale is used based on the following data ranges: 0.8-1.0 for high, 0.6-0.79 for medium and <0.6 for low.

Figure1Sites are ranked from highest to lowest resilience (from 1 through to 268).  Resilience scores are presented spatially on two maps; one that uses a 3-bin stoplight color system of green, yellow and red for high, medium and low, respectively (see Figure 1), and another that sets resilience scores into 10 equal (0.10) bins. Principle Components Analysis (PCA) is used to identify commonalities among the scores for the various indicators for high, medium, and low resilience sites; i.e., whether some resilience indicators more greatly influenced the final rankings and in what way (see Figure 2). The results were then shared with managers and stakeholders to identify and prioritize potential follow-on actions.


How successful has it been?
All of the set objectives were met by the analysis or will be met over the coming months by using analysis outputs to engage with stakeholders and community members. It is not anticipated that this analysis will be used to create additional Marine Protected Areas right now. However, the results may be used to review MPA placement in the future and will inform a range of other management actions over the coming years that will support the resilience of St. Croix’s reefs. As an example, preliminary data suggests there is a positive and significant correlation between the resilience score from this analysis and known spatial variation in the survivorship of transplanted corals. The analysis results will now be used to determine where nursery-grown corals are most needed and have the greatest potential for restoration success. The analysis will be extended in the coming year to include reefs near St. Thomas and St. John to better target conservation effort across all 3 islands.

Lessons Learned and Recommendations
Lessons learned and key recommendations include:

  • Resilience assessments can be completed as a desktop-exercise using existing data (the case here).
  • The most critical first step is the identification of clear objectives.
  • The process of selecting indicators collaboratively ensures partners and stakeholders are intellectually invested in the assessment.
  • Collaboration generated through the consultations used to select indicators increases buy-in, which maximizes uptake of the analysis outputs.
  • Resilience assessments including multiple sites and indicators require investing effort in data management. Data need to be in one location and all data for indicators needs to be standardized such that comparisons can be made among sites.
  • Maps describing the relative resilience of sites and graphs describing the relative influence of each of the indicators on the final rankings help to simply and visually explain the analysis and its value to partners and stakeholders.
  • The completion of a desktop-based resilience assessment will identify ways field monitoring programs can be modified to collect more or better information on resilience indicators. The exercise may also help to identify better ways of storing field data such that future resilience assessments can be completed quickly and less resource-intensively than the first.

Funding Summary
This project was funded by The Nature Conservancy through its office in St. Croix, USVI and in partnership with NOAA’s Coral Reef Conservation Program.

Lead Organizations
The Nature Conservancy

NOAA Coral Reef Conservation Program
NOAA NCCOS Biogeography Program
NOAA National Coral Reef Monitoring Program
USVI Department of Planning and Natural Resources
USVI Division of Fish and Wildlife

Coral Reef Resilience to Climate Change in Saipan, CNMI: Field-based Assessments and Implications for Vulnerability and Future Management

Coral Reef Module pages: Analyzing Relative Resilience; Assessing and Monitoring Reef Resilience; Selecting Resilience Indicators

Saipan, Northern Mariana Islands Resilience Assessment Case Study

How-to Guide for Conducting Resilience Assessments (pdf, 1.3M)

Prioritizing Key Resilience Indicators to Support Coral Reef Management in a Changing Climate (pdf, 373k)

Operationalizing Resilience for Adaptive Coral Reef Management Under Global Environmental Change (pdf, 542k)

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Northern Mariana Islands – Monitoring Reef Resilience

Field-based Assessments of Coral Reef Resilience to Climate Change in Saipan, Commonwealth of the Northern Mariana Islands

Saipan, Commonwealth of the Northern Mariana Islands (CNMI)

The Challenge
Coral reefs worldwide are threatened by a combination of global and local stressors. In the Commonwealth of the Northern Mariana Islands (CNMI), managers are working together to address these threats and to assess the resilience of coral reefs. Identifying sites with high resilience potential can inform a range of management decisions to support and maintain the natural resilience of coral reefs. Many have been working to develop frameworks that enable reef resilience to be assessed and compared among sites. In the months before this fieldwork, a framework was published that suggests 11 variables (or ‘resilience indicators’) be evaluated to compare the resilience potential of coral reef sites. These are: coral diversity, bleaching resistance, recruitment, herbivore biomass, macroalgae cover, temperature variability, nutrient input, sedimentation, fishing access, coral disease, and anthropogenic physical impacts (McClanahan et al. 2012). This case study describes the first field-based implementation of the McClanahan et al. (2012) framework in Saipan, CNMI.

Actions Taken

The 11 resilience indicators were measured or assessed at a total of 35 sites around the island of Saipan in May and June of 2012. Details on the methods used can be found here. To calculate a relative resilience score, the following method was used. The value for each indicator for each site was expressed as a percentage relative to the maximum value for that indicator among all sites. This practice is called ‘anchoring’ and normalizes the data to a standard scale of 0-1 (the percentages are expressed as decimals). The resilience scores calculated are the average of the scores for the 9 indicators included in the analysis (the variables above minus coral disease and anthropogenic physical impacts, which were not observed), and the sites were ranked from highest to lowest resilience score. The relative categories high, medium and low were used to describe the scores for all indicators and for the resultant resilience scores.

23 sites were found to have high relative resilience; 9 sites have medium, and 3 have low (see Table 1 below). Principal Components Analysis revealed that rankings were most strongly driven by coral diversity, bleaching resistance and macroalgae cover. Without exception, sites with the highest resilience, relative to other sites surveyed, have high coral diversity, high bleaching resistance and low macroalgae cover. Low coral diversity, low bleaching resistance, and high or at least medium macroalgae cover characterize low resilience sites. High and medium resilience sites are located throughout all of Saipan’s reef habitats while the low resilience sites are all in the Saipan lagoon.

Table 1. Final resilience scores and rankings for the survey sites. Anchored (to the max value) and normalized (uni-directional 0-1 scale) scores for all 9 variables are shown to the right. Resilience scores are the average scores for all variables, then anchored to the highest resilience score (column right of rank). High relative resilience potential includes the range (0.8-1.0), medium (0.6-0.79), and low (<0.6).

Table 1 Resilience Scores and Rankings

How successful has it been?

Based on the resilience analysis, the project team made a number of suggestions to coral reef and coastal managers working in CNMI:

  1. For management actions that result in benefits that take many years or decades to manifest – like marine protected areas – we suggest that sites with higher relative resilience potential deserve greater consideration. Further, we suggest reducing anthropogenic stressors to the extent possible at the sites assessed as having the highest resilience potential.
  2. Sites with greater coral diversity and low macroalgae cover deserve special consideration from managers as these may be high tourism value sites.
  3. Actions resulting in improved water quality on reefs will affect the resilience potential of the greatest number of sites (versus other actions).
  4. Protecting herbivorous fish populations is especially important at locations with greater relative vulnerability to coral bleaching.

Sites were identified that met the following conditions: high resilience, greater coral diversity, low macroalgae cover, or were more vulnerable to coral bleaching, or some combination of those. All of the various suggestions made have resulted in action by local natural resource agencies in CNMI. Actions include: communication and outreach, updating management plans, re-assessing water quality treatment, and strengthening partnerships with tourism operators. The agencies tasked with allocating conservation and management resources and effort around Saipan are also responsible for other reef areas within CNMI. For that reason, the project team will soon extend the analysis and work to include reef sites near Tinian and Rota, which have lower levels of anthropogenic stress.

Lessons Learned and Recommendations
Collecting all of the data required to undertake a resilience assessment is a resource-intensive exercise and requires many people with different types of expertise. Using existing datasets is strongly recommended to reduce the cost of the assessment. In many coral reef locations, multiple agencies and groups will benefit from the analysis results and outputs so cost-sharing is possible and should be explored.

Including many agencies and perspectives can increase buy-in and maximize uptake but may mean it will not be possible for everyone to be entirely satisfied with the final methods. Assessing spatial variation in exposure to anthropogenic stressors can be especially controversial, so the final approaches used for anthropogenic stressors need to be developed transparently and collaboratively.

Assessing the relative resilience of reef sites generates information that can be used to make resilience-based management decisions; i.e., decisions resulting in the targeting or tailoring of management actions to support the natural resilience of coral reefs. Completing the assessment is not an endpoint in itself, and the capacity to conduct an assessment is not reason enough to undertake the assessment. It is critical to consider first how the assessment results and outputs will be used. A list of information needs is included on the Assessing and Monitoring Reef Resilience page. An assessment may be justified when it meets one or more of those needs.

Funding Summary
The Western Pacific Coral Reef Institute and the University of Guam supported parts of the project as did the CNMI Coral Reef Initiative, which had a grant from NOAA’s Coral Reef Conservation Program and Senator Gregorio Kilili Sablan.

Lead Organizations
NOAA Fisheries
CNMI Division of Environmental Quality 
The Nature Conservancy
Pacific Marine Resources Institute

University of Guam
Western Pacific Coral Reef Institute
NOAA Coral Reef Conservation Program
CNMI Coastal Resources Management
CNMI Division of Fish and Wildlife

Coral Reef Resilience to Climate Change in Saipan, CNMI: Field-based Assessments and Implications for Vulnerability and Future Management

Coral Reef Module pages: Analyzing Relative Resilience; Assessing and Monitoring Reef Resilience; Selecting Resilience Indicators

US Virgin Islands Resilience Assessment Case Study

How-to Guide for Conducting Resilience Assessments (pdf, 1.3M)

Prioritizing Key Resilience Indicators to Support Coral Reef Management in a Changing Climate (pdf, 373k)

Operationalizing Resilience for Adaptive Coral Reef Management Under Global Environmental Change (pdf, 542k)

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Palau – MPA Design

Designing a Marine Protected Area Network in Palau

Palau, Micronesia

Rock Islands, Palau. © Stephanie Wear (TNC)

Rock Islands, Palau. © Stephanie Wear (TNC)

The Challenge
Palau is located approximately 800 km east of the Philippines, and consists of a series of islands approximately 459 km2 in total size. Palau’s coral reefs are considered to be one of the “Seven Underwater Wonders of the World.” Located on the north-eastern margin of the Coral Triangle, Palau’s coral reefs have both high species diversity and high habitat diversity. Palau’s reefs contain more than 350 species of hard corals, 200 species of soft corals, 300 species of sponges, 1,300 species of reef fish, and endangered species such as the dugong, saltwater crocodile, sea turtles, and giant clams. In addition to Palau’s diverse marine resources, it has the highest terrestrial biodiversity of all countries in Micronesia.

The immediate threats to Palau’s biodiversity result from the inappropriate use of natural resources, such as overharvesting and sedimentation due to tourism activities, development, population growth, and economic development. Similar to other areas within Micronesia, climate-induced coral bleaching is an ongoing threat. Having previously suffered high levels of coral bleaching and mortality following the 1998 El Niño event, the predicted increase of El Niño associated bleaching events could create even greater devastation to this area. Despite these threats, Palau’s landscapes and seascapes remain relatively intact.

Coral bleaching during the 1998 bleaching event was as high as 90% at some sites, with average mortality reaching 30%. The northern reefs of Palau suffered the most while most corals on fringing reefs around the rock islands in the southern lagoon escaped bleaching. Corals living in turbid waters adjacent to a river mouth were spared as well. The shading factor of both the rock islands and turbid water is believed to have helped corals to escape bleaching. However, corals that were spared because of the turbid water died a few years afterwards as siltation increased due to increased soil runoff from the construction of the ring road around Palau.


Palau: A Case Study (7:21)
Local leaders discuss the 1998 bleaching event in Palau.

Palau's coral reefs have both high species and high habitat diversity. Assessing the biodiversity of the area was a step in the development of the Protected Area Network. Photo © Paul Marshall

Palau’s coral reefs have both high species and high habitat diversity. Assessing the biodiversity of the area was a step in the development of the Protected Area Network. © Paul Marshall

Actions Taken
In 2003, the Protected Areas Network Act (PAN Act) was passed by the Palau National Congress. This landmark legislation provides a framework for Palau’s national and state governments to collaborate to establish a nationwide network of terrestrial and marine protected areas with the aim of protecting the biodiversity and natural resources of value to future social, cultural, economic, and environmental stability of Palau. These goals complement those of the Micronesia Challenge that aims to have each country within Micronesia conserve 30% of near shore environments, and 20% of terrestrial environments, by the year 2020.

In 2008, President Remengesau signed the revised PAN Act, which includes the establishment of a non-government corporation, the Protected Areas Network Fund (PANF), and the creation of a Green Fee (a $30 fee collected from visitors to Palau upon departure from the airport). This fee is used for management of PAN sites (a site that becomes part of the protected areas network by meeting certain ecological criteria). Only PAN sites are eligible to count towards the Micronesia Challenge. To date, over $3 million USD has been collected from the Green Fee.

MPA Design
When designing the Protected Areas Network (PAN), The Nature Conservancy’s reef resilience model incorporating effective management, representation and replication, critical areas, and connectivity was used. Two workshops in 2006 set out to develop a set of protected area design principles, stratification, conservation targets and goals and to provide a range of PAN scenarios for review by workshop participants. Multiple PAN variables were considered, including size, landscape context, current condition, threats, costs, and conservation goals. In 2012, another workshop was held to determine how to incorporate fisheries and climate change principles to improve the design of the Palau PAN. MARXAN was exceptionally useful in this process, as it is designed to help synthesize and automate the selection process by integrating both biodiversity and socioeconomic criterion that often conflict. Specifically, MARXAN attempts to identify scenarios that meet conservation goals, with minimal impact on socioeconomic values.

An Ecoregional Assessment of Palau was conducted in multiple steps. In 2002, twenty-four targets were selected for initial analysis using the Spatial Portfolio Optimization Tool (SPOT), which produced a variety of portfolios representing different protected area scenarios. Based on the SPOT analysis, it was determined that a variety of scenarios could accomplish protection goals; however, more work was needed to improve the quality of the data, and to complete the mapping of missing targets. Therefore, the second phase of planning focused on using the MARXAN tool.

Steps of the Ecoregional Assessment included:

  • Identifying biodiversity targets (species to communities);
  • Mapping occurrences/distributions of biodiversity targets and maintaining a database of information relevant to each target;
  • Identifying conservation goals for each biodiversity target;
  • Identifying areas of high biodiversity value (e.g., areas that support multiple targets, rare species, and/or help maintain ecosystem processes); and
  • Analyzing the threats and causes of high biodiversity areas and targets.

As of 2012, there were 13 PAN sites, including 5 terrestrial and 8 marine sites. These sites have rigorously undergone the Palau PAN application process and have met all the requirements. They all have management plans that are being implemented. All sites are entitled to the Palau PAN funding (Green Fee). Some of these sites have been evaluated using the Micronesia Protected Areas Management Effectiveness Evaluation (MPAME) and the scores range from management level 1-3, with management level 5 being the highest management level that can be attained.

In 2012, the Ministry of Natural Resource Environment and Tourism (MNRET) officially adopted monitoring protocols in support of management of PAN that were developed by the Palau International Coral Reef Center (PICRC) with funding and technical support from the Japan International Cooperation Agency (JICA). This protocol provides a framework for monitoring key biological and physical indicators for assessing effectiveness of management in contributing to achieving the goals of PAN.

How Successful has it been?
Almost 10 years after the bleaching event, coral reefs of Palau that suffered the bleaching event showed tremendous recovery. Coral reef monitoring data by the Palau International Coral Reef Center since 2001 shows rapid recovery in deeper water (10 m) followed by recovery in shallow water (3 m). This recovery is thought to be facilitated by coral remnants and recruitment from less impacted habitats. Furthermore, recovery of the Acropora corals was highest on the western slopes of Palau, believed to be a result of high post settlement survival and favorable growth conditions. A recent unpublished larval dispersion model by Palau International Coral Reef Center showed higher larval retention on the west, consistent with the observed recovery and coral conditions.

Palau’s coral reef recovery from the 1998 bleaching event shows resilience when key coral reef ecosystem functions are maintained (herbivory, stable substratum quality, water quality) and human impacts (land based) are managed. Prior conservation efforts to manage Palau’s coral reefs through establishment of protected areas may have had a positive contribution to the recovery process. With the establishment of PAN legislation and regulations, many of the existing MPAs met the established criteria for membership with the network. This is a positive contribution to achieving the goals of the network because rather than focusing on getting sites established, the focus has been on improving site management. Improving site management ensures that the key ecological process needed for the maintenance of coral reef health that contribute to reef resilience are maintained.

The monitoring program set up during the resilience assessments of the PAN made it possible to conduct a rapid assessment during a thermal stress event in July-August 2010. This rapid assessment was performed at 80 sites to examine the spatial extent and severity of bleaching. Results showed that coral bleaching was significantly higher on outer and patch reefs than in bays, and was more severe in the northwestern lagoon. The study shows that reefs around the bays are more tolerant to thermal stress than patch and outer reefs, and the reefs in the bays are valuable refuges to buffer coral reef ecosystems against climate change impacts.

Lessons Learned and Recommendations

  • Reducing/managing land-based sources of stress to the marine environment will help build resilience of reefs through rapid recovery following major natural disturbances.
  • Healthy herbivore populations on reefs will facilitate coral recovery through ensuring clean substrate for recruitment and may facilitate post recruitment survival by reducing algal overgrowth.
  • Long-term monitoring is important for documenting disturbance and understanding reef resilience provides valuable information to inform site selection for enhanced management and prioritization of limited human and financial resources for management.
  • Designing a resilient protected areas network will require adaptive learning as new and improved data are made available to inform the spatial coverage of the network.
  • Community-based conservation efforts are an important local response that can build the resilience of reefs in response to impacts of climate-related events.

Funding Summary
The Nature Conservancy
The Wallis Foundation
Government of Palau (in kind)
Palau International Coral Reef Center (in kind)
Japan International Cooperation Agency
German Lifeweb
National Oceanic and Atmospheric Administration
US Fish and Wildlife Service

Lead Organizations
The Government of the Republic of Palau
Ministry of Resources and Development

The Nature Conservancy
Palau Automated Land and Resources Information System (PALARIS)
Other government offices: Bureau of Agriculture, Bureau of Marine Resources
Coral Reef Research Foundation
Palau International Coral Reef Center
Palau Conservation Society

Biodiversity Planning for Palau’s Protected Areas Network, An Ecoregional Assessment (pdf, 3.8M)

Palau: Communities Manage Watersheds and Protect Reefs

Acropora size frequency distributions reflect spatial variable conditions on coral reefs of Palau (pdf, 508k)

Moving Toward Measuring Our Effectiveness: The 2nd Meeting of the MC Measures Working Group and PICRC-JICA Coral Reef Monitoring Project Meeting (pdf, 4.6M)

Spatial variability of coral bleaching in Palau during a regional thermal stress event in 2010 (pdf, 1.2M)

Monitoring Protocol Workshop Report (pdf, 635k)

Protocol for Monitoring Marine Protected Areas Protected Areas Network (pdf, 258k)

MPA Management Effectiveness Progress Report (pdf, 2M)


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