Regeneration remedy
Corals show promise one year post extinction scare, but seabed looks like ‘a graveyard’
Published:Tuesday | October 29, 2024 | 12:10 AMAsha Wilks/Gleaner Writer
A year ago, Jamaica’s coral reefs were on the verge of going extinct because of a massive coral-bleaching emergency caused by rising sea temperatures and climate change.
Today, coral reef scientist Felix Charnley is declaring that his quick action in leading a rescue mission has proved successful, with 276 surviving colonies being discovered by himself and his colleagues through their mapping exercises across St Ann, Trelawny, and sections of St Mary.
Speaking with The Gleaner yesterday, Charnley shared that the two coral reef nurseries, which are set up in Tower Isle, St Mary, and Mammee Bay, St Ann – within the Ocho Rios marine park – now have 107 colonies in culture and 1,458 replicates.
“At one site, we have 1,000 replicates in culture. We have about 40 or so colonies in Mammee Bay represented but, in total, there are 1,000 clones. And then, at White River [Fish Sanctuary], we have about 49 colonies represented and not as many clones, but we’re getting there,” he said.
These mapping missions began last year.
According to Charnley, his goal has not been to restore hectares of degraded reefs by transplanting the surviving coral colonies, which are currently being housed in nurseries to the reef. Rather, he has been primarily concerned with making sure that the diversity of corals found is kept alive and can be assessed more easily.
He stated that while corals can regrow and recover by themselves over time, this was a unique situation which called for human assistance to preserve the ones which had not perished.
“I would rather keep them in the safe, relatively free environments provided by nurseries ... where they don’t have to compete with algae and where we can put in place mitigation measures like seasonal shading, or maybe even implement probiotic feeding,” he said.
In a December 2023 interview with The Gleaner, Charnley stated that around 90 per cent of the country’s corals had died during a two-month span – from September to October.
That number soon climbed to 99 per cent as the months went on.
Suffering severe damage as a result of the bleaching episode were two of the most important reef-building coral species in the Caribbean – elkhorn ( Acropora palmata) and staghorn ( Acropora cervicornis).
Fortunately, Charnley surveyed 191.64 kilometres, or approximately one quarter of Jamaica’s coastlines, and conducted an additional 233 semi-monthly re-swims to preserve the colonies of corals that had been entirely or partially bleached but alive, or those which were otherwise unaffected.
According to more recent reports, other endangered species that were inventoried include the fused staghorn ( Acropora prolifera) and pillar coral ( Dendrogyra cylindrus).
Charnley told The Gleaner that the sea floor remains in a terrible shape following last year’s bleaching incident.
A GRAVEYARD
“We are now seeing all of those dead [coral] skeletons either break down or just become more overgrown with algae. It’s just a graveyard,” he said.
He revealed that, before the bleaching incident, he would observe a coral every 10 minutes while swimming. Now, he has to swim for around eight hours to spot a single survivor coral.
“Humans need to back off,” Charnley said, noting that human beings are a primary stressor to the environment.
He listed overfishing and ocean pollution as examples of harmful human activities which reduce the likelihood of the reefs recovering on their own.
Charnley added that, because algae has taken over the reefs, natural coral colonisation no longer occurs. Thus, the corals have an extremely low survival rate and require human aid to recover.
The restoration works that Charnley and the White River Fish Sanctuary sought to conduct cost approximately US$50,000 in their first phase, and approximately US$500,000 in their subsequent phase. Among other things, this entails mapping exercises and the use of assisted fertilisation techniques to increase the corals’ rate of reproduction.
In January, Charnley and his colleagues were visited by Matthew Samuda, then minister without portfolio in the Ministry of Economic Growth and Job Creation.
At the time, Samuda said the Government was committed to preserving the coral population and would provide financial assistance to local non-governmental organisations (NGOs) and enlist the support of international partners to secure funds to tackle the destruction.
LATE RESPONSE
He revealed that, while the CAF-Development Bank of Latin America and the Caribbean had extended an offer of millions of dollars to support the rehabilitation work, the Government neither accepted the invitation nor offered its endorsement.
He said assistance from government finally arrived 11 months later, with the National Environment and Planning Agency giving each sanctuary $1 million to continue the rescue works.
The Tourism Enhancement Fund also contributed $14 million.
For just over a year, Charnley was employed to the White River Fish Sanctuary. This is his last week there.
While he will be working in St James on a coral project, he told The Gleaner that he will make every effort to carry on with the work, but notes that the sanctuary is now in an outstanding position, both nationally and internationally, because of the genetic diversity in its nurseries.
“I hope to see more coral projects pop up along the coast, thanks to the work that I have done in finding the material to work with. So, fingers crossed on that, but it’s all about getting that support,” he said.
He expressed regret that the government’s financial assistance had arrived at such a late point in the project, but he also stated that work could go on with these resources.
“My efforts have definitely not been wasted, I hope,” he added.
July 2023 was officially recognised as the hottest month in recorded history. Similarly, sea surface temperatures were persistently high and above 29 degrees Celsius, the threshold point at which corals begin bleaching.
More recently, July 2024 was declared the warmest July on record by the National Oceanic and Atmospheric Administration, with temperatures 0.03 degrees Celsius (0.05 degrees Fahrenheit) higher than in July 2023.
Research shows that the climate event referred to as El Niño affects the Caribbean by causing the conditions to become dry, or very dry and warmer, which leads to extended droughts, significantly affecting ecosystems and biodiversity.
Meanwhile, in some regions of the Americas, El Niño manifests itself with increased rainfall, generating floods, landslides and disasters.
The Gleaner reported in January that, over in the small island of Tobago, coral-bleaching was experienced, particularly affecting the brain coral ( Diploria labyrinthiformis), the largest species of coral in Tobago’s reefs that is also highly susceptible to disease.
Additionally, the mountainous star coral ( Orbicella faveolata), believed to be one of the main reef-building corals in Tobago, and the boulder star coral ( Orbicella annularis) representing approximately 15 to 23 per cent bleaching.