A Caribbean bright spot coral reef exceeds thermal limits during the fourth global coral bleaching event

Marine heatwaves are increasing in both frequency and intensity, exposing coral reefs to prolonged periods of thermal stress and driving recurrent mass coral bleaching. Nevertheless, coral decline remains heterogeneous, with some reefs maintaining unexpectedly high coral cover despite exposure to thermal and other environmental disturbances. This study analysed benthic community change across Banco Capiro in Tela Bay and the south-side reefs of Utila, Honduras, from 2013 to 2025, spanning the 3rd and 4th Global Coral Bleaching Events. Banco Capiro represents a moderately turbid, Caribbean bright spot for live hard coral cover, whereas Utila represents a more typical contemporary Caribbean reef system. Long-term benthic monitoring data, NOAA Coral Reef Watch thermal stress metrics, Generalised Additive Mixed Models and multivariate community analyses were used to quantify changes in benthic cover and community composition. Banco Capiro experienced repeated annual thermal stress, with Degree Heating Week values reaching 12 °C-weeks or above in 2017, 2019, 2020 and 2021, and nearing 20 °C-weeks in 2023 and 2024. Before 2023, live hard coral cover was high at Banco Capiro, averaging 45 ± 3% (mean ± SE), but declined to 4 ± 1% (mean ± SE) following the 4th Global Coral Bleaching Event. Macroalgal cover increased from 26 ± 4% (mean ± SE) to 44 ± 3% (mean ± SE), while turf algae increased from 6 ± 2% (mean ± SE) to 23 ± 8% (mean ± SE). Utila also experienced further coral loss after 2023, despite entering the event from an already lower-coral state. These findings indicate that previous persistence does not guarantee survival under more extreme disturbance.