We can “teach” corals how to withstand the increasing temperature
- Global warming is the greatest threat to coral reefs.
- Projects about coral restoration have expanded around the world to replenish habitats with corals affected by different stressors.
- However, these restoration efforts will be of no use if outplanted corals cannot withstand the warmer oceans and high-temperature events.
- Stress hardening is one of the approaches to increase the temperature tolerance of corals currently grown for restoration.
- Scientific evidence suggests that environments with varying temperatures can reduce coral bleaching during exposure to thermal stress.
- However, it is still unclear if this localized adaption to varying temperatures can be used to enhance coral restoration efforts.
- Researchers treated fragments of Caribbean staghorn coral with variable and static temperatures in the laboratory for 89 days.
- The variable temperatures oscillated two times per day from 28 °C to 31 °C, while the static temperature was set to 28 °C.
- The fragments were then exposed to heat stress at 32 °C for 2 weeks.
- Corals in the variable temperatures showed signs of severe thermal stress later than corals in the static temperature and untreated field controls.
- Additionally, corals in the field control groups showed a higher incidence of tissue degradation while corals in the variable temperatures give way to bleaching at a slower pace.
- The study highlights the importance of variable temperature exposure to improve thermal tolerance of corals.
- The discovery will be important for future research and restoration of corals affected by climate change.
DeMerlis, A., Kirkland, A., Kaufman, M.L. et al. Pre-exposure to a variable temperature treatment improves the response of Acropora cervicornis to acute thermal stress. Coral Reefs (2022). https://doi.org/10.1007/s00338-022-02232-z