While I was in discussion with a local environmental agency one of their support officers touched on the problems facing the world’s coral reefs. A quick search of the web revealed that we have plenty to worry about. A recent report by the Global Coral Reef Monitoring Network (GCRMN) the International Union for Conservation of Nature and the United Nations Environment Program claims that with only about one-sixth of the original coral cover left, most Caribbean coral reefs may disappear in the next 20 years.
For the Caribbean, loss of any coral reef could spell disaster for the tourist industry. Aside from tourism, dead or dying reefs put pressure on already declining fish stocks, and the thought of a lifeless ocean is not one I want
Islands such as Bonaire pride themselves on their diving, yet conservationists there recently planted more than 1,200 nursery-raised corals onto selected reef restoration sites. One of the people behind the scheme is Francesca Virdis, Coordinator of the non-profit Coral Restoration Foundation Bonaire (CRF). I contacted Ms Virdis to find out more about why reefs are in trouble and learn about their restoration work.
Virdis began by telling me that compared to reefs on other islands; Bonaire’s reefs are quite healthy although they had declined over the last 30-years.
“A growing population adds to problems of localized pollution and this, along with the increasing severity of storms and bad weather puts the reefs under increasing pressure. Today, it’s difficult for the coral to recover from pollution, coral bleaching and viruses. Shallow water coral is affected the worst close inshore.”
With the help and instructions of volunteers from the Key Largo headquarters of the Coral Restoration Foundation, CRF Bonaire have planted nursery raised staghorn (Acropora Cervicornis) and elkhorn (Acropora Palmata) coral on five restoration sites.
There are a number of methods for growing coral. In Bonaire they are using what is known as a Coral Tree Nursery. This is a simple framework that resembles the shape of a tree. Corals are fragmented and attached to the coral tree arm using wire or monofilament line. The ‘tree’ is tethered to the sea floor and buoyed with a subsurface floatation device that allows for 360 degrees water movement around the corals, which results in a more rapid growth rate. Suspended in the water column, the tree is able to move with storm generated wave surges. This dissipates wave energy preventing damage to the tree structure or corals.
Bonaire’s coral tree nurseries have been expanded and can now produce around 7000 corals per year. The corals take six to nine months before they are ready to be taken to be planted on selected reef sites.
“To restore 150 square feet of reef requires 2000 corals. We can make a difference,” Virdis said.
Tourists that visit Bonaire and other Caribbean islands to dive the reefs, bear some of the responsibility for their decline. “Divers love the reefs but some don’t realize how fragile they are,” notes Virdis. She adds that buoyancy control is vital when diving on the reefs.
Bonaire is proactive when it comes to their reefs, and mandates that all visiting divers refer to a dive shop and attend a marine park orientation course before they enter the water.
Virdis holds a degree in marine environmental science and, along with her duties with the CRF, is a dive instructor for Buddy Divers. She spends a lot of time in the water. Observations recorded by her and her team—and other divers around the Caribbean—are critical if the reefs are to survive.
The GCRMN report did offer a ray of hope. According to the authors, restoring parrotfish populations and improving other management strategies, such as protection from overfishing and excessive coastal pollution, could help the reefs recover and make them more resilient to future climate change impacts.
When it comes to healthy reefs, CRF Bonaire is leading the way.