MESOAMERICAN REEF – The 2024 Mesoamerican Reef Report Card was released today by Healthy Reefs for Healthy People (HRHP), in collaboration with over 70 organizations dedicated to the conservation of the Mesoamerican Reef (MAR) in Mexico, Belize, Guatemala and Honduras that collectively form the Healthy Reefs Initiative (HRI). This regional initiative provides robust, useful data and promotes partnerships that enable ecosystem-based management and adaptive conservation of the Mesoamerican Reef. For this Report Card we had a total of 93 data collectors of 42 organizations dedicated to reef conservation.
Since 2008 these Reef Health Report Cards have tracked indicators of reef health over time: live coral cover, fleshy macroalgae cover, and the biomass of key herbivorous and commercial fish species. The collaborative monitoring uses standardized methods and data from hundreds of sites to provide a comprehensive analysis. Reef Health can be assessed for each indicator or for the integrated Reef Health Index, which equally considers all four indicators. Evaluations can be considered at the site, subregion, country or full Mesoamerican Reef scale.
The findings of the 2024 report offer a mix of hope and urgency, despite some improvements the overall health of the reef system is fragile and facing increasing threats.
The health of the Mesoamerican Reef remains a concern, with most of the 286 monitored sites categorized as either in poor (39%) or critical (23%) condition. However, sites in fair and good condition have improved, rising from 20% to 28% and 5% to 9% respectively. More of the 18 subregions saw improvements than declines, yet none are now classified as being in good condition, and two are considered critical.
Key Findings:
- Coral health has been severely impacted by disease outbreaks and bleaching, reducing coral cover from 19% to 17%. Alarmingly, mortality continued even after surveys concluded. The 2023 bleaching event was the most severe on record, with approximately 40% of corals severely affected, and significant mortality observed at several iconic reef sites.
- Fish populations: On a positive note, commercial fish biomass increased by 40%, largely due to stronger enforcement measures. Herbivorous fish biomass also saw a 30% rise, though it’s worth noting that 9 out of 10 parrotfish remain under 30cm, and species with higher herbivory potential are still uncommon. The population of larger fish species, such as snappers and groupers, remains concerning, with 67% of snappers and 78% of groupers being immature. This emphasizes the need for more fisheries regulations and community-led fishery management initiatives to allow commercial species to reach maturity and replenish stocks.
- Management: The statistics for Marine Protected Areas (MPAs) have shown little change, particularly regarding the percentage under Full Protection. However, stronger enforcement appears to have led to higher fish biomass within Fully Protected and Highly Protected To further protect marine ecosystems, it is crucial to establish science-based limits on size, catch, and fishing efforts, while also achieving the goal of designating 20% of the sea as Fully Protected Zones. The active involvement of fishers in fisheries management, alongside transitional economic support and training, is essential to achieving these objectives.
- Water quality concerns: High nutrient levels, particularly in the southern region, and unacceptable concentrations of human sewage pathogens continue to jeopardize reef health. Both government and private sector investments are needed to implement tertiary wastewater treatment with effective management systems and to enforce national regulations aligned with the Cartagena Convention’s water quality standards. Defining tourism carrying capacities in coastal zones is necessary, and the Mesoamerican Reef should be declared a Particularly Sensitive Sea Area (PSSA) to ensure its long-term protection.