DoE battling coral reef decline

The fight against coral decline is something the DoE is actively pursuing, but it is no easy feat, especially with a new bout of coral bleaching in the Caribbean basin posing another potential regional problem for our reefs.

Last week an expert on coral reef ecology and marine biology at the University of Puerto Rico, Professor Ernesto Weil was in Grand Cayman with Mr. Aldo Croquer who is doing a post-graduate Doctorate on coral diseases.

They visited three reef sites in Grand Cayman waters (two in the North Sound, Andy’s Reef and Pinnacles and one to the south of the island, Pallas Reef West) to assess the health of the reefs. In summary, Mr. Weil said that of the three reefs he saw, coral cover is low, there is disease, a lot of algae, but the population of fish is better than in other places in the region.

He said that the whole Caribbean is connected and it is such a close region that there has to be an international effort to help the coral reefs, which are declining regionally and globally.

Speaking about the huge global problems of global warming and reef decline, Director of the Department of Environment Ms Ebanks-Petrie said that these are factors that we cannot control. She stressed that each Government needs to manage its own resources so when the countries are added together it amounts to something significant.

The DoE’s most urgent need is to get legislation passed to allow for a framework to regulate human activity, she said.

‘We need to take on board the numbers of people on the reefs, sediment and nutrient pollution. These are things we actually have control over.’

Mr. Croy McCoy of DoE’s Research Department noted that there is a pretty severe bleaching event going on in the Caribbean basin and this would likely cause some more reduction in coral cover here.

Data from the DoE’s reef monitoring programme shows that in line with another acute global bleaching event in 1998, there was an absolute decline of coral cover between the years 1997 and 1999, ranging from 2 per cent to 20 per cent at sites, with a corresponding increase in algal abundance, which DoE notes is cause for concern. Data shows that the decline seems to have stabilised between the years 1999 through 2004. ‘This event (of 1998), along with a general increase in coral diseases over the past decade will most certainly have contributed to the observed reduction in coral cover. The stability between 1999 and 2004 suggests that coral cover may have reached equilibrium and is presently coping with the higher algal profusion. Statistical results at most sites showed no significant differences in live coral cover during this period,’ Mr. McCoy explained.

The DoE scientific coral reef monitoring programme is in it ninth year in the Cayman Islands. The photographic methodology involves comparison and analysis of repeated photo evidence taken annually at 27 permanently marked reef sites all around the Cayman Islands.

The DoE notes that the programme has allowed it to contribute comparative data regionally and globally, thereby fostering a better understanding of the dynamics, impacts and trends that coral reefs are undergoing. In addition, it has provided a wealth of information on how to better manage Cayman’s reefs.

‘Everything we’ve seen highlights the need not to do really stupid things, like anchoring cruise ships off coral reefs,’ said Ms Ebanks-Petrie

‘We’re trying to approach the problem of climate change from many different angles,’ she added. ‘That way we can see the success of local impacts,’ she said.

Ms Ebanks-Petrie noted that the Government has signed up to the United Nation Framework Convention on Climate Change and its Kyoto protocol. This commits participants to individual, legally binding targets to limit or reduce their greenhouse gas emissions.

The DoE has been involved in a joint project with the UK’s renowned Tyndall Centre for Climate Change Research for the past three years.

Mr. Weil said that while they discovered low coral cover in the deeper areas, there were lower levels of disease from when he visited before in 2002. However, this could be put down to there probably being less coral down there now.

The deeper areas were disease affected, they found. At one site, below 80ft they saw a high prevalence of plague, which seems to be moving down the reef, he said.

In the South, the shallow areas were vastly changed as a result of the storms, with a lot of coral breakage. However, Mr. Weil said he believes that in the long term the reef will recover from this storm damage, as reefs adapt to this type of event, and the storm would have cleansed the reefs from algae. ‘In my opinion the storms will be beneficial in the long-term,’ he said.

In relation to the causes of coral diseases, he said there is no clear answer. The emergence of new diseases is probably linked to environmental changes and the movement of pathogens from one environment to another.

The Department of Environment conducts water quality tests at two sites in Grand Cayman, one off George Town Harbour and the other in the North Sound. This is time consuming and the Department is currently looking for a way to gather this information without having to use so much manpower.

The DoE has already gathered lots of data and found that over a 14 year period at the GT Harbour there are very low levels of nutrients in the water. Over the past two years in the North Sound they have not found excessively high levels of nutrients but have found spikes at certain areas such as at the mouth of the more developed canals and from the landfill.

Mr. Weil said that it appeared that there were more varieties of fish at the three reefs visited than in other areas of the region.

From data the DoE has collected, the protected areas of Cayman waters (marine parks) have done what they were set up to do, but now it is time to look more seriously at them and to convince the Government and public that more needs to be done, said Ms Ebanks-Petrie.

‘What was good in 1986, when the parks were put in place, has served its purpose, but we need to change these in line with the impacts we’re beginning to see,’ she said.

Since there is so much we do not know relating to global warming and coral disease, the applying of good common sense to the management of marine resources becomes necessary, she asserted.

‘We’re doing everything we can do, as the Department of Environment, to manage the coral reefs,’ she said. However, she warned that to go the extra mile, reef management would have to involve some sacrifices from others, for example, in greater enforcing the management of protected areas. ‘There are so many things beyond our control it makes those under our control all the more important,’ she said.