Monthly Archives: January 2012
Acropora palmata coral
While cataloguing the coral collection in the Herbert museum, I came across this species of Acropora coral.
Acropora are a genera of coral that contains at least 149 separate species. Acropora palmata has been the subject of recent conservation efforts as its numbers have suffered dramatically in the last 30 years. Acropora palmata is listed as critically endangered by the International Union for Conservation of Nature. This is the tier before ‘extinct in the wild’.
Acropora palmata is found in the Caribbean Sea, Florida, the Gulf of Mexico and the Bahamas. These corals primarily live in shallow waters with temperatures between 26 °C and 30 °C.
Corals rely on zooxanthellae, which are photosynthetic protozoa that embed themselves in coral tissue. The zooxanthellae receive protection from predators and in return supply the coral with approximately 90% of its energy from their photosynthetic byproducts. These protozoa are extremely sensitive to variations in water temperature and will leave the coral tissue if long periods of temperature change occur. The result is ‘bleached’ coral as the colourful zooxanthellae leave. Global warming, the rise in sea levels and temperatures have massively affected the symbiotic relationship between corals and these protozoa.
Corals are also suffering world-wide because they are extremely susceptible to pollution, acidification of the sea and changes in ocean salinity. Human activities such as tourism and fishing also pose a threat to coral.
All these factors have affected corals on the global level, but the spread of an aggressive disease called ‘White band disease’ has hit the Acropora palmata species hard. It is estimated that 80-98% of the wild population has been wiped out in the last 30 years.
It is entirely possible that Acropora palmata could soon only be alive in cultivated aquariums.
University of Leicester work placement student
Acropora palmata in the wild.
Photo by Nick Hobgood. Sourced from Wikimedia Commons.