February 26, 2018

Coral Reefs in Crisis, Require Comprehensive Remediation Strategies

By Dr. Jean-Luc Solandt, Marine Conservation Society & Coordinator for Reef Check Maldives

As a result of climate change and other anthropomorphic stressors, coral reefs are suffering a decline in both species populations and diversity, according to Dr. Jean-Luc Solandt, who presented Reef Check Maldives/IUCN findings at the recent three-day European Coral Reef Symposium attended by almost 600 delegates in Oxford, England. Solandt reported the following key points of the conference:

  1. Corals are in crisis, with increasing evidence of a shift to Porites genera rather than Acropora genera in the Indo-Pacific.
  2. Bleaching can actually lead to resilience in some corals and in the zooxanthellae clades; researchers have observed evidence of acclimatization to further warming events by the coral hosts themselves.
  3. Some corals (Porites, such as Thailand’s intertidal brain corals) can \”shrink down\” into the calix better than can others to avoid thermal stress.
  4. Modelling has shown that the Great Barrier Reef can recover from last year’s bleaching, as there are node reefs (3% of the system) that have not bleached that may resupply up to 47% of the whole complex with larvae.
  5. Ecosystem function can be maintained when 50% of the biomass and diversity of reef fish are exploited on reefs.
  6. Many reefs show algal abundances coincident with localized wave-induced upwelling, a newly described natural phenomenon.
  7. Reef conservation efforts worldwide must persevere through stakeholder interaction, identifying new opportunities, and fostering capacity building efforts.
  8. Corals show incredible breeding \”plasticity,\” with incredibly sophisticated brooding, sperm selection and timing of spawning. 'Pushing' evolution by exploiting thermal tolerances and through forced fertilization of individuals can lead to greater thermal tolerances.
  9. Grouper spawning populations are in trouble in the Maldives, even in isolated atolls away from larger population centers.
  10. Coral reef restoration is far costlier than is preventing damage/collapse in the first place, with projections of over US$150K for protecting a hectare of Thailand’s reefs.

\”Much of the upshot of this,\” continues Solandt, \”is that many scientists are desperate to find academic ways to solve the current problems. However, the necessary scale of remediation, or putting things in practice that could mitigate at whole-reef scale or national/regional scale, is not being invested in so far. A mega project that takes into account (bullet points) 4,6,7 and 8 above may be able to provide the mechanisms to support recovery in resilient ecosystems.\”

Kudafalhu, Maldives. Healthy reef… …to algae