Corals in Musandam are thriving, report finds

When it comes to the health of corals, Musandam's waters were in better condition than many locations famous for being scuba-diving haunts.

Musandam’s coral reefs are among the healthiest in the region, a study has found. Courtesy of Biosphere Expeditions

MUSANDAM // A survey of the peninsula by an expedition of marine scientists and volunteer divers has found that its coral reefs are thriving.

The team surveyed eight dive sites in the area from October 6 to 12 last year, studying the density and variety of corals, fish, invertebrates and other marine creatures as well as recording factors such as water temperature and salinity. The team’s findings were published in a report in April.

For most of the dives at depths below 12 metres, coral cover of about 55 per cent was recorded. In addition, the reefs appeared healthy with “little evidence of any coral disease, bleaching or predation”, said the report.

For Dr Jean-Luc Solandt, an expedition member and one of the authors of the report, said when it came to the health of corals, the sites were in better condition than many locations famous for being scuba-diving haunts.

“It is an outstanding location,” said Dr Solandt, senior biodiversity policy officer at the Marine Conservation Society. “The coral health is excellent.”

The expedition was organised by Biosphere Expeditions, a non-profit conservation organisation that relies on volunteers working alongside scientists. This is the fifth annual coral survey carried out by the group along the northern Musandam coastline.

While the overall diversity of coral species was low – attributed to the large concentrations of plankton blocking sunlight to the reefs, as well as other challenges of the local marine environment – some species appeared to be not only well adapted but also thriving.

The healthy Musandam reefs could well be a source of population recovery for reefs in the Arabian Gulf, where physical and man-made factors combine to create an environment that is more challenging for corals.

Many of the sites hosted very large colonies of the genus Porites. Some of the colonies, said Dr Solandt, were “the size of small houses”, indicating they could well be more than 400 years old.

This also most likely meant that no significant damaging events had occurred within this timeframe, said the report.

Besides having great conservation value, the old colonies are also “really useful for scientists”, said Dr Solandt. By analysing the chemicals present in samples of the older coral tissue, scientists can find out about the factors affecting the development of the reefs in the past.

“You can get climate records that are up to 400 years old, which is very important,” he said.

The expedition also measured the abundance of various marine species. While numbers of herbivorous fish, important for the well-being of corals by keeping concentrations of algae in check, were high, predatory fish, in particular the orange-spotted grouper, or hammour, were harder to find.

“They were missing,” said Dr Solandt of the hammour, a species whose numbers have significantly declined after years of overfishing.

“I did not see too many of a large size,” he said, explaining that all hammour are female in the early stages of their lives, with some changing sex as they mature.

Being caught at a young age thus significantly limits the chances of the population to reproduce.

The report concludes that while “Musandam probably hosts the most well-developed coral reefs of the region in a unique area of natural beauty as well as commercial importance”, several measures need to be taken to protect it.

Some of the recommended steps concern the management of fishing. They include enforcing minimum and maximum landing sizes for reef fish, and minimum landing sizes for invertebrates, as well as banning fishing during certain times important for species such as groupers and keeping some important areas off limits for fishermen.

The next expedition is planned for the end of October this year.