From documenting coral reef decline to forecasting coral resilience

CIMAS scientist Anderson B. Mayfield, Ph.D. explores moving from simply observing and recording coral decline to predicting their fate.

Through years of monitoring and tracking the fate of, experimenting on, and simply photographing reef-building corals across the Indo-Pacific and the Caribbean, my colleagues and I have amassed data that suggest that, though still aesthetically appealing and perceivably “healthy” to even the highly trained eye of an observant ecologist, most framework-building corals are in a perpetual state of stress on account of the rapidly increasing temperatures brought on by global climate change. Doom and gloom aside, these data are frustrating to me because, in the end, these findings really just amount to another marine biologist (yours truly) complaining about climate change and its impacts on coral reefs. Could I have used these data not merely to write coral reef obituaries, but instead to help their plight by, for instance, identifying “refugia” (i.e., locations where organisms persist despite presumably marginalized environmental conditions)?

vibrant coral reef near Baa Atoll
A vibrant coral reef near Baa Atoll, Maldives (photo taken by the author). This reef is now nearly entirely devoid of live corals on account of climate change-associated seawater warming.

Rather than exclusively surveying and sampling dying reefs, or slowing killing corals in laboratory aquaria to see how they respond to environmental change, I have recently been trying to think more like an actuary and instead use the insight gained from such analyses to make predictions about the fate of corals as Earth’s seawater temperatures continue to climb. Although your life insurance company may not have your estimated date of death down to a particular year, there are physiological benchmarks, such as blood pressure, that have long-term health implications. Corals may not have blood, but they present other molecular and physiological characteristics that could be diagnostic of declines in health, or, alternatively, hallmarks of resilience. 

Through a series of studies carried out at the University of Miami’s (UM) Rosenstiel School for Marine and Atmospheric Sciences (RSMAS) by both CIMAS and National Oceanic and Atmospheric Administration (NOAA) scientists, we have recently characterized the coral stress response and uncovered what occurs within the cells of resilient corals that resist climate change and other anthropogenic stressors. Upon profiling the proteins synthesized by both stress-susceptible and environmentally resilient corals, we then developed an artificial intelligence (AI) platform that can correctly predict whether a coral will bleach or persist through a future marine heatwave. With this molecular biology + AI approach, we can now transcend simply counting the number of bleached and diseased corals and start predicting which we may need to keep an eye on, and which (if any) will weather the storm to come.

scleractinian coral-dominated community

A scleractinian coral-dominated community in Indonesia’s Banda Islands (photo by author). These stony corals had colonized a lava flow left in the wake of a volcanic eruption (“Gunung Api” or Api Volcano in Indonesian).

Such predictions of coral and reef resilience are now being integrated with more popular reef health models derived from global temperature trends alone (e.g., NOAA’s Coral Reef Watch) such that oceanographic (e.g., temperature), ecosystem (e.g., coral cover and diversity), and physiological data from the resident corals are collectively used to rank reefs along a resilience spectrum, from near-death to markedly robust (coral reef “triage”). By shifting the paradigm from exclusively documenting reef decline, via the explanatory scientific approaches familiar to most marine biologists, to predictive analytical tools—once the domain of only meteorologists and the odd fisheries statistician—we may soon have the power to predict the fate of reef corals over decadal timescales and consequently identify potential refugia.

January 14, 2021

Top