Coral reefs

Coral reefs are marine habitats made of calcium carbonate dominated by scleractinia corals thought to descend either from Paleozoic rugose coral or an anemone-like Mesozoic ancestor. Some extant Scleractinia genera date back to the Jurassic period, such as the Faviidae, commonly known as brain coral, still a major family after 150 million years. Scleractinia geological longevity manifests their survival to multiple extinction episodes. Coral reefs have assisted fish evolution in the Miocene epoch by providing a safe haven that promoted extensive diversification during prolonged extinction events. Contemporary deep water coral reefs resemble these ecological refugia and demonstrate an outstanding lifespan. The underlying skeleton of a deep water Leiopathes colony found in Hawaii was determined to be more than 4 000 years old, making it the oldest skeletal-accreting marine organism known.

Coral colony resilience, as impressive as it may be, does not change the fact that by mid-century most of the world's coral reefs will be threatened.. Though they do regenerate after tropical storms and other natural perturbations, coral around the world have succumb to human repercussions, fueling the debate concerning their survival. Some suggests that since coral reefs have recovered from the impacts of climate change time nad again, show adaptation to rising sea temperatures and a heterogeneous response to acidification, their process of degeneration could be slower, less widespread and not as uniform as anticipated. On the other hand, according to the International Panel on Climate Change, even if some coral reefs might manage to adapt to thermal stress, one third most likely won’t and instead degrade within a few decades. Accelerated fishing, ocean acidification and pollution are held responsible for the global coral reef demise, these anthropogenic pressures having reduced Caribbean coral reefs by 80% over half a human lifespan.

Photo credit: Gary M. Stolz, U.S. Fish and Wildlife Service

Photo credit: Gary M. Stolz, U.S. Fish and Wildlife Service

The Caribbean’s mostly fringing reefs act as wave breakers on islands particularly vulnerable to climate-related intense weather, erosion and sea-level rise. For example, the Jamaican reefs off Discovery Bay are thought to reduce by 23% the impact of flooding and high seas. In areas of Long Bay in Negril, the absence of reefs has accounted for 83% of erosion.

A coral polyp is an animal that looks somewhat like a plant: growing out of the calcium carbonate trunk-like skeleton that it excretes and topped by a mouth of leaf-like tentacles. Coral pieces can be broken off, cultivated and transplanted on deteriorated and artificial reefs with relative ease. However, coral gardens must be meticulously cleaned by hand until they settle due to the depletion of herbivores. The recovery of transplanted coral takes 2 to 5 years.

In Negril, coral reefs have shifted to macroalgae dominance. Once upon a time, offshore waters were tinted gold by branching acroporid corals that skimmed the ocean’s surface. Recreating such a pristine landscape is feasible, albeit ambitious, with the help of coral gardening and artificial reefs.

Coral gardening at Oracabessa Bay Fish Sanctuary, Jamaica: https://scontent-yyz1-1.xx.fbcdn.net/v/t1.0-9/1472939_668666646497975_69657683_n.jpg?_nc_cat=110&ccb=3&_nc_sid=cdbe9c&_nc_ohc=89fqQfHvU20AX8r4nSG&_nc_ht=scontent-yyz1-1.xx&oh=c9ad8c7a2da7f05da3187937952f4eeb&oe=605B2018

Acropora recovery in Jamaica

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