Increasingly frequent marine heatwaves are devastating coral reefs. Corals that survive these extreme events must rapidly recover if they are to withstand subsequent events, and long-term survival in the face of rising ocean temperatures may hinge on recovery capacity and acclimatory gains in heat tolerance over an individual’s lifespan. To better understand coral recovery trajectories in the face of successive marine heatwaves, we monitored the responses of bleaching-susceptible and bleaching-resistant individuals of two dominant coral species in Hawai’i,
Global climate change is altering coral reef ecosystems. Notably, marine heatwaves are producing widespread coral bleaching events that are increasing in frequency, with projections for annual bleaching events on reefs worldwide by mid‐century. Responses of corals to elevated seawater temperatures are modulated by abiotic factors (e.g. environmental regimes) and dominant Symbiodiniaceae endosymbionts that can shift coral traits and contribute to physiological legacy effects on future response trajectories. It is critical, therefore, to characterize shifting physiological and cellular states driven by these factors and evaluate their influence on in situ bleaching (and recovery) events. We use back‐to‐back bleaching events (2014, 2015) in Hawai'i to characterize the cellular and organismal phenotypes of Despite fewer degree heating weeks in the first‐bleaching event relative to the second (7 vs. 10), We demonstrate that repeat bleaching triggers cellular responses that shift holobiont multivariate phenotypes. These perturbed multivariate phenotypes constitute physiological legacies, which set corals on trajectories (positive and/or negative) that influence future coral performance. Collectively, our data support the need for greater tracking of stress response in a multivariate context to better understand the biology and ecology of corals in the Anthropocene.
A free
- NSF-PAR ID:
- 10451074
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Functional Ecology
- Volume:
- 35
- Issue:
- 6
- ISSN:
- 0269-8463
- Page Range / eLocation ID:
- p. 1366-1378
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Plain Language Summary can be found within the Supporting Information of this article. -
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