Abstract:
High-latitude coral communities exist in variable environmental conditions and provide an opportunity to study the response of biological communities to changing environmental conditions. A 30-year monitoring dataset, initiated in 1993, was used to investigate how biological communities have changed in relation to environmental parameters over time. During the study period, major components of the sessile benthic community underwent periods of stability and significant phase shifts, where hydrocoral and sponge cover declined while macroalgal cover increased, with no recovery to observed historical states in more than a decade. However, despite the significant changes in major components of the benthic community, scleractinian coral cover and community composition have remained remarkably unchanged, albeit low (4%). This stability suggests the coral community had a degree of tolerance to environmental stress over a thirty-year period. Through gradient forest analysis, mean temperature and reduced water clarity were the environmental variables associated with changes in the benthic community. High-latitude reefs may act as sentinel sites for future coral resilience research, helping to inform coastal and offshore resource protection and management.
