Identification of coral disease within the high-latitude reef, Lord Howe Island Marine Park.

Abstract Coral disease prevalence has significantly increased under a changing climate, impacting coral community structure and functionality. The impacts and ecology of coral diseases are unclear in most high-latitude reefs. High-latitude locations are vulnerable to climate change; therefore, identifying diseases and developing region-specific baselines are important for local management. We report the first coral disease findings at UNESCO World Heritage Lord Howe Island Marine Park (31.5°S, 159°E), the southernmost coral reef system. Coral disease prevalence was recorded during November 2018, March and October 2019. Four coral diseases were identified from three reefs, white syndrome, skeletal eroding band, growth anomalies and endolithic hypermycosis impacting six coral taxa (Acropora, Isopora, Monitpora, Pocillopora, Porites and Seriatopora). Overall, disease prevalence was 5 ± 1%, and was highest in November (10 ± 1%) and significantly lower during March (5 ± 1%), coinciding with a bleaching event. White syndrome was the most prevalent disease (4 ± 1%) with 83 colonies of six taxa affected, predominately Isopora. Acroporids recorded the highest disease susceptibility, with three of the four diseases observed. Documenting baseline coral disease prevalence and monitoring throughout a bleaching event assists our understanding of disease ecology dynamics under current climate change impacts at high-latitude reefs.