What are we doing to our beautiful oceans

Around 4,000 species of fish, that’s 25 % of all marine life are dependent on coral reefs at some point in their life cycle. Added to that half a billion people globally depend on coral reef ecosystems for food, coastal protection, and income from tourism and fisheries.

The reefs in the Bay Islands have so far escaped the fate of the rest of the Caribbean. In the eastern Caribbean (including USAs only live reef in Florida), 0nly 18% of coral is estimated to be alive and well but here it was 70%. Covid helped all reefs as tourism and the damaging effects of too many cruise ships allowed them to recover and only 6 months ago I was diving the reef here and it was gloriously healthy. A virus affecting certain hard corals that spread down from Florida was a worry but the healthy Bay Islands reef seemed to be shrugging it off.

What I am seeing just a short time later is tragic and I found tears prickling the corners of my eyes beneath the scuba mask. Swimming over the reef today is like looking down from a jet flying over the Rockies or Alps. The peaks are all turning white - coral bleaching is everywhere you look. It’s thought the record-breaking hot summer raised bottom temperature and higher than usual rainfall may have added to the stress. Coral feeds on the symbiotic algae that live inside and on it but when temperatures rise the algae produces a toxin and in an effort to protect themselves the corals eject the algae. They effectively starve to death leaving only the bleached calcium skeletons. This is a well managed marine park with protected fishing areas, regulated diving and no anchoring policies so if it is happening here think what’s happening where those protections don’t exist.

The rate of decline in the worlds reefs is scary and there are no recorded incidences of mass bleaching anywhere on the planet before the 1980s. Now reefs in both hemispheres are I n trouble so this is very much a problem of our time and almost certainly of our making.

There is some hope. Most of the corals are only partially bleached so its hoped that as winter sea temperatures fall the algae will repopulate the bleached areas but if temperatures continue to rise this will only be a temporary respite turning rich habitat into a watery desert.