Predation is a fundamental ecological process that shapes marine ecosystem dynamics. This study reveals a novel predator–prey interaction between the giant Caribbean sea anemone Condylactis gigantea and the two jellyfish species Cassiopea sp. and Aurelia sp., challenging traditional understanding of sea anemone feeding habits. Observations from citizen science platforms and field recordings documented C. gigantea successfully capturing and consuming these gelatinous marine organisms. The research highlights the trophic plasticity of C. gigantea, demonstrating its ability to prey on larger gelatinous organisms beyond its traditionally known diet. This predation event represents a possible benthic–pelagic coupling mechanism and underscores the value of citizen science in capturing rare ecological interactions.

Coral reefs provide environmental goods and services that support biodiversity and people but face diverse threats. To assess the human factors that might be influencing the status of Cuban coral reefs, we collected and analyzed data from three sources: observations made on a research cruise that circumnavigated Cuba’s waters, expert knowledge, and updated published information. Our results show that small-scale fisheries are predominant among human factors influencing Cuban coral reefs, with more than 97% of the fishing incidents detected in situ during the expedition. Many Cuban reefs are heavily fished, have low levels of contamination, and enjoy high legal protection but experience inadequate enforcement. Tourism occurs on many reefs but could be sustainably increased based on its role in supporting enforcement and compliance and reducing fishing pressure. Densities of marine debris were generally lower in Cuban waters than other Caribbean locations and even lower within protected areas. Many human factors are likely acting synergistically, making management a challenge. This is the first at-sea comprehensive visual survey of human factors in Cuban waters and evaluation of marine debris on Cuba’s reefs, establishing a baseline for future assessments. These findings highlight potential human impacts that must be addressed to safeguard the health of Cuba’s marine ecosystem.

The reef fish communities of the Guanahacabibes National Park have been studied for 20 years using various methodologies that have allowed us to understand aspects of their diversity and structure. However, due to gaps in information about the abundance and distribution of mesopredators (big fish and sharks), a new study was conducted in 2017 to determine their structure, explore the influence of different factors on their spatial variability, and evaluate their behavior. To achieve this, the Baited Remote Underwater Video Surveys (BRUVs) methodology was successfully applied, locating a single set of BRUVs at 90 sites distributed across 9 sectors of the park’s functional zoning. Variability in mesopredator metrics and their potential prey was assessed through a PERMANOVA analysis; a distance-based linear model (DISTLM) was used to explore the relationship between mesopredator abundance and biological, abiotic, and condition variables; and animal behavior was classified as incidental, cautious, or aggressive. A total of 64 fish species were identified, 7 of which were mesopredators, and 3 were sharks. An uneven distribution and abundance were observed among sectors, with the most abundant mesopredators being Carcharhinus perezi, Sphyraena barracuda, and Mycteroperca bonaci. Mesopredator abundance was more closely related to the condition of zone use and its regulations than to biological and abiotic variables. Sharks were more abundant in strictly protected areas, which coincided with relatively murky waters and stronger currents. More than 50% of the observed sharks displayed exploratory and aggressive behavior towards the bait basket. The analyzed metrics validate the effectiveness of the management of the protected area and suggest the presence of healthy and resilient mesopredator fish communities.

Microplastic contamination in coral reef environments is increasingly recognized as a global concern; however, the extent to which polymer composition can resolve contamination sources and transport processes remains poorly understood. In this study, we assessed the abundance, composition, and diversity of microplastics (< 300 µm) across multiple reef systems in the Cuban archipelago using high-resolution spectroscopic analysis. Microplastic abundance varied substantially among sites, with a median concentration of 66 particles L⁻¹ (IQR: 45–115 particles L⁻¹), ranging from 8 to 218 particles L⁻¹. A total of 11 polymer types were identified, with polyethylene (PE), polypropylene (PP), and polyamide (PA) dominating the assemblages and accounting for approximately 77% of detected particles. While these polymers were consistently observed across all sites, indicating a pervasive regional background signal, highly impacted reefs exhibited more complex polymer profiles, including the enrichment of polyurethane (PU), polytetrafluoroethylene (PTFE), and polyvinyl chloride (PVC), reflecting localized anthropogenic inputs. Multivariate analysis revealed distinct compositional groupings associated with different contamination regimes. Notably, some sites exhibited elevated microplastic abundances while remaining dominated by common polymers, indicating a decoupling between contamination levels and source-specific signatures. This pattern suggests that regional transport and mixing processes, including circulation through the Caribbean basin and the Yucatán Channel, play a major role in shaping microplastic distributions in reef environments. These findings demonstrate that polymer composition provides critical information beyond abundance alone, enabling the differentiation between source-driven contamination and transport-driven accumulation. The integration of polymer-specific analysis with abundance and diversity metrics offers a robust framework for improving source apportionment and informing monitoring and management strategies in coral reef systems.

Microplastic contamination in coral reef environments is increasingly recognized as a global concern; however, the extent to which polymer composition can help distinguish contamination sources and transport-related processes remains poorly understood. In this study, we assessed the abundance, composition, and diversity of microplastics (20–300 µm) across multiple reef systems in the Cuban archipelago using high-resolution Laser Direct Infrared (LDIR) spectroscopic analysis. Microplastic abundance varied substantially among sites, with a median concentration of 66 particles L⁻¹ (IQR: 45–115 particles L⁻¹), ranging from 8 to 218 particles L⁻¹. A total of 11 polymer types were identified, with polyethylene (PE), polypropylene (PP), and polyamide (PA) dominating the assemblages and accounting for approximately 77% of detected particles. While these polymers were consistently observed across all sites, suggesting a pervasive regional background signal, highly impacted reefs exhibited more heterogeneous polymer profiles, including increased contributions of polyurethane (PU), polytetrafluoroethylene (PTFE), and polyvinyl chloride (PVC), consistent with localized anthropogenic influence. Multivariate analysis revealed moderate compositional structuring among reef sites and suggested broad differences in polymer assemblages associated with contrasting contamination settings. Notably, some reefs exhibited elevated microplastic abundances while remaining dominated by common polymers, indicating a partial decoupling between contamination levels and polymer-specific signatures. This pattern is consistent with the influence of regional transport and mixing processes across the Caribbean basin, potentially including circulation associated with the Yucatán Channel, although hydrodynamic processes were not directly assessed in this study. Overall, the findings highlight the value of polymer-resolved analysis for improving interpretation of microplastic contamination patterns in coral reef environments. The integration of polymer composition with abundance and diversity metrics provides a useful framework for distinguishing between localized contamination signals and broader regional background influences. This study represents a regional baseline assessment of small microplastics in Caribbean coral reef systems using high-resolution spectroscopic characterization.