Reef-coral refugia in a rapidly changing ocean

Area of Science:

• Marine Biology
• Climate Change Ecology
• Conservation Science

Background:

• Coral reefs face significant threats from climate change-induced thermal stress.
• Understanding species-specific responses to thermal stress is crucial for predicting future distributions.

Purpose of the Study:

• To identify climate-change thermal-stress refugia for reef corals in the Indian and Pacific Oceans.
• To predict the impact of rising ocean temperatures on coral species distribution by 2100.

Main Methods:

• Species distribution modeling using contemporary geographic ranges and thermal preferences.
• Application of downscaled global climate model outputs to predict future habitats.
• Modeling with and without a 1°C capacity for coral adaptation to warming.

Main Results:

• A positive exponential relationship exists between current and predicted coral habitat area.
• Nine of 12 species are predicted to lose 24-50% of their habitat, primarily between 5-15° latitude.
• Adaptation capacity (1°C) could allow some species to retain habitat, while Porites lobata may expand its range.

Conclusions:

• Five Indian Ocean and seven Pacific Ocean refugia were identified for reef corals.
• Despite local adaptation, some species may become 'losers' at regional scales due to warming.
• Identified refugia warrant high conservation status to protect coral biodiversity.