As rising sea temperatures and increases in the frequency, duration, and intensity of
marine heatwaves threaten coral survival at a global scale, research on the capacity of
corals to acclimatize and adapt to changing environments has become a high priority.
Understanding how environmental parameters shape coral thermal performance
across habitats is crucial to identify populations with high vulnerability or high
thermal tolerance to future ocean warming. In recent studies, corals from high
temperature variable environments (HVE) have shown increased thermal tolerance
compared to corals from low temperature variable environments (LVE). Here, I
investigate if these phenotypes are shaped by acclimatization, habitat-specific
adaptation, or a combination of both, in the branching coral, Acropora hemprichii, by
reciprocally transplanting individuals between a back (HVE) and front reef (LVE).
After ten months of acclimatization, comparisons of photosynthetic efficiency
(photosystem II), mortality, and bleaching recovery was assessed for > 2 months
between coral ramets following a natural bleaching event in the central Red Sea. In
tandem, coral bleaching severity and recovery in each reef environment was assessed
to genus level by photographic surveys of fixed belt transects. Bleaching between reef
sites was compared against bleaching in treatments to differentiate the role of habitat specific adaptation and acclimatization in the corals. This study aims to elucidate the
evolutionary mechanisms driving coral habitat-specific thermal stress tolerances,
which may inform coral reef management and restoration efforts.
|Date of Award||Jul 2021|
|Original language||English (US)|
- Biological, Environmental Science and Engineering
|Supervisor||Manuel Aranda (Supervisor)|
- transplantation, thermal tolerance, coral, bleaching