The team was funded by the Leverhulme Trust (UK), through an International Network Grant. It included scientists from James Cook University and The University of Queensland in Australia, from The University of Auckland in New Zealand, Memorial University in Canada, and the University of Maine in the USA. They examined rates of carbonate production across 19 reefs in the four Caribbean countries of the Bahamas, Belize, Bonaire and Grand Cayman.
They discovered that declines in rates of carbonate production were especially evident in shallow water habitats, where many fast growing branching coral species have been lost. The study compared modern day rates with those measured in the region over approximately the last 7,000 years. In key habitats around the Caribbean, the findings suggested that in waters of around five metres in depth, reef growth rates are now reduced by 60-70% compared to the regional averages taken from historical records. In waters of around 10 metres in depth, the rates are reduced by 25%.
The study also suggests that these key habitats must have a minimum of around 10% living coral cover to maintain their current structures. The amount of cover varies between sites, but some are already below this threshold and are therefore at risk of starting to erode. Given that previous studies have shown that coral cover on reefs in the Caribbean has declined by an average of 80 per cent since the 1970s, this raises alarm bells for the future state of reefs in the region. These changes have been driven by human disturbance, disease and rising sea temperatures, and are only expected to intensify as a result of future cl
|Contact: Louise Vennells|
University of Exeter