x Abu Dhabi, UAEMonday 24 July 2017

Saving the wonders of the deep

The Gulf's coral reefs are among the most threatened on the planet. As a group of the world's leading marine biology experts meet in Abu Dhabi this week, an army of amateur divers is fighting the problem, John Henzel reports.

Scientists worry increasing pollution and ocean acidity will kill even Gulf reefs, which have proved unusually resistant to climate change's rising temperatures and increased ocean salinity.
Scientists worry increasing pollution and ocean acidity will kill even Gulf reefs, which have proved unusually resistant to climate change's rising temperatures and increased ocean salinity.

If coral reefs are the marine ecosystem equivalent of canaries in a coal mine, then those in the UAE are definitely not chirping away happily on their perches.

A combination of increasing salinity, rising temperatures and pressure from development all have an effect on the region’s reefs, which are not only recognised as ecologically unique and internationally significant, but also among the most at risk in the world.

Within 40 years, researchers predict that every reef in the region will be classified as threatened.

Just how serious that threat is will be assessed this week by a team of 15 of the world’s leading reef-health experts, who will visit reefs on the Arabian Gulf and Indian Ocean coastlines of the UAE as part of an initiative by New York University Abu Dhabi Institute.

Their findings will be assisted by a baseline created by more than 100 amateur divers in the UAE who have joined Reef Check, an international group that trains volunteers in 90 countries to conduct health assessments on reefs to determine if conditions are stable, improving or deteriorating.

Reef Check was founded in the United States in the 1990s but has only really taken off in the UAE in the last few years, with increasing numbers of divers paying to complete a three-day training course to ensure the veracity of their results.

One of them is Kate McQuaid, a Dubai-based environmental manager who has done three assessments for Reef Check, off the coast of Abu Dhabi and Dibba, and aims to do more.

Even though she is an experienced diver who completed her masters in marine environments, Ms McQuaid says the experience of doing reef-health assessments has made her see the coral in a new way.

“It gives you a different perspective because you learn to see things in more detail, like the hard and soft corals,” she says. “The focus is also on indicator species like snapper, grouper, parrot fish and hump-headed wrasse. The more of these guys you see, the healthier the reef is.

“In the big picture, you look at the coral itself and see if it’s bleached – there have been a couple of major events in recent years of coral bleaching [from thermal stress].

“The coral in the [Arabian] Gulf is more degraded. It is also more at risk in terms of development, in the form of dredging and land reclamation.

“The biodiversity and dynamics on the east and west coasts are completely different – the colours of the coral and the range of species are different.”

Divers can only conduct Reef Check assessments once they pass a three-day training course.

Two days are spent in the classroom learning to correctly identify Indo-Pacific fish species, invertebrates and different kinds of substrates, corals and sponges. The third day is in the water, including a practice assessment to ensure their findings have veracity.

“It’s pretty stringent,” Ms McQuaid says. “You have to have a good idea about what you’re identifying.”

The pass mark for the written section is 80 per cent, but for the practice dive, volunteers must correctly identify species 90 per cent of the time to qualify to conduct Reef Check assessments.

The stringency is important. If the initial results are flawed, later visits could indicate that the reefs are improving or deteriorating when the opposite could be true.

Even with a cost of Dh600 for the privilege to become Reef Check volunteer, more than 100 divers have joined up since the group became active in the UAE.

Other volunteering organisations have adopted Reef Check’s methods to conduct research in the area.

Biosphere Expeditions has carried out three annual surveys on five selected sites at the tip of the Musandam peninsula to provide a baseline.

Based on shallow (2-5-metre) and deeper (6-12m) transects that were inspected in 2009, 2010 and 2011, the coral was found to be increasing, although researchers are not sure why.

Biosphere’s sites were chosen in part because they were at the nexus between the entirely different environments found inside and outside the Arabian Gulf.

The UAE’s coast features salinity levels up to half as high again as regular seawater, caused by a combination of evaporation rates exceeding inflow from rivers by seven to one, and by the effect of desalination plants.

The east coast has salinity levels similar to average seawater but has been affected by a series of red tides that devastated reef life, exacerbated by the effects of Cyclone Gonu in 2007. Since 2009, the east coast marine ecosystem has bounced back.

The World Resources Institute, an environmental think tank based in the US, said the Arabian Gulf’s coral reefs were deemed unique and internationally significant because the coral evolved to cope better with high temperatures and salinity than anywhere else on earth.

But as both increase further, the coral’s capacity to cope is exceeded, an effect exacerbated by pressure from development of the coastal environment.

Using satellite-sourced water temperature readings, bleaching is measured in the form of degree heating weeks (DHWs). If the sea-surface temperature is one degree higher for one week than the statistical average for that time of year, a DHW of one is recorded. If it is two degrees higher for four weeks, the DHW rating is eight.

Scores of eight typically result in severe bleaching and some coral death.

Reef Check’s assessment of the Middle East’s reefs, which also includes the Red Sea and the Arabian Sea, also identified them as unique because they are isolated from the rest of the world’s coral population, with no coral to be found on the coastlines of Pakistan or Somalia.

The Arabian Gulf is also characterised by very low diversity but with species that had adapted to the high temperatures and salinity, including an ability to cope better with a wider variation between winter and summer water temperatures than any other reef system.

Reef Check says this makes the Arabian Gulf “a living laboratory for better understanding the effects of temperature and the potential for adaptation”, making this region useful as a predictor for how other reefs around the world will cope with the effects of climate change.

But the group assessed that more than 85 per cent of the reefs in the Arabian Gulf are considered threatened, making them the most imperilled reefs in the region, and there had been patterns of “intense and destructive bleaching”.

The other challenge is the abrupt increase in population living on the southern Arabian Gulf, combined with booming economies that allow major development in the shallow waters where the reefs formed.

“Corals throughout the [Arabian] Gulf are in poor condition. Large areas were impacted by coral bleaching in 1996, 1998 and 2002. Recovery has occurred, but has been slow, particularly on reefs close to population centres,” the Reef Check report states. “Measures of live coral cover in the [Arabian] Gulf are typically only 5 to 10 per cent of the total reef surface.

“Thermal stress and ocean acidification are projected to increase threat levels to nearly 90 per cent by 2030, while by 2050 these climate change impacts, combined with current local impacts, will push all reefs to threatened status, with 65 per cent at high, very high, or critical risk.”

This is the grim picture being assessed by the 15 marine biology experts who are in Abu Dhabi this week, summoned by NYUAD Institute for a conference on the biology of coral reefs in extreme environments.

Part of the focus is that, as other parts of the world face higher temperatures and salinity levels, the Arabian Gulf’s reefs will serve as a useful predictor for how they adjust to the changing climate.

At which point researchers will determine if the reefs in this region are more like a canary in a coal mine, or akin to the parrot in the Monty Python sketch.

jhenzell@thenational.ae