Coral reefs cover a mere 0.2% of the world’s oceans, yet they house over a million different species and produce a substantial proportion of the world’s oxygen.  However, these ‘rainforests of the sea’ have declined by nearly 50% in the past 50 years.

Sea temperature rise, sedimentation, ocean acidification, pollution, and overfishing are all key contributors to the overwhelming statistic that approximately six-tenths of the world’s reefs are now at risk due to human activity.

Coral reefs are unique and delicate structures made up of tiny individual organisms called polyps.  Living within the polyps are tiny microscopic algae called zooxanthellae, which give the magnificent structures their bright colors.  The two organisms live in a symbiotic relationship, whereby they provide each other with essential requirements including nutrients and shelter.  A coral is said to be ‘bleached’ when the polyps expel the zooxanthellae from their structure due to environmental stress.

Coral reefs are extremely sensitive and can only live within the narrowest band of environmental conditions, with even the smallest of changes having severe detrimental effects.  For example, in 2005 a sea temperature rise of just one degree centigrade between July and November resulted in the bleaching of 90% of the coral in the US Virgin Islands (1).  Coupled with the onset of disease and the increased stress on the corals, 51.5% of the coral was lost during the following 12 months (1).  These shocking statistics are not isolated; they are evident around the globe.

So how can we help to prevent the loss of arguably one of the most important ecosystems on earth?  It’s surprisingly easy!  There are many small steps that anyone can take that will make a huge difference:

  • Conserve water. The less water you use, the less waste water that will end up as run off in the oceans.
  • Don’t throw your trash in the ocean. It endangers both the coral reef and the organisms that live within the reef ecosystem.
  • Don’t use chemical fertilizers or pesticides. They will eventually end up in the ocean having detrimental effects on the coral.
  • Are you a diver? If so, don’t touch! Make sure your fins and tank are away from the coral so it doesn’t get damaged.  One little branch could have taken hundreds of years to grow!
  • Use public transport! Emissions from fossil fuels contribute to sea temperature rise, thus in turn bleaching the coral.
  • Spread the word! Many people are unaware of the threat that coral reefs are under…so tell them!  Unless you spread your knowledge and passion, this essential ecosystem will be lost from our oceans.





About the Author: Growing up with a passion for the ocean, Mieles now  spends her time teach marine science and water sports.  Any spare moment is spent on the water catching some wind or waves at her local beaches in South Wales!