Swimmers were advised to stay out of the sea yesterday as government scientists continued to test for a harmful algae bloom that has devastated marine life in other emirates.Evidence of the bloom, known as red tide, could be seen off the coast of the Palm Jumeirah and close to the Atlantis Hotel. Nakheel, the Palm developer, yesterday issued a statement from EHS-Trakhees (Environment, Health & Safety) informing residents that because of the “potential risk due to direct exposure to algae we advise the public to avoid contact with affected water”
Seawater samples were taken by Dubai Municipality on Thursday with more due to have been taken yesterday to test whether the algae is toxic but the results are not expected for up to a week. Patches of brownish water, signifying the presence of algae, have been spotted between eight and 13 nautical miles offshore between Palm Deira and Palm Jebel Ali.

There were also sightings of “significant” patches of algae around the World island development yesterday.

Algae-contaminated water has also been seen from the Corniche in front of the Atlantis hotel. It is understood that the hotel experienced problems with its water intake earlier this week because of the bloom. The resort needs seawater for its extensive aquarium and water-park facilities.

The Atlantis has not issued any warnings to its guests, but in the letter issued by Nakheel, signed by Dr Abdulmonem Almarzouqi, manager, environmental regulations of EHS-Trakhees, and posted in public areas on the Palm, it said the bloom was “caused by an algae species known as Cochlodinium sp., a non-toxic species initially identified by analysis. Further investigation into the toxicological implications of this algae species is still ongoing.”

Preliminary results suggest the type of algae causing the Dubai bloom is similar to the one responsible for the death of hundreds of tonnes of fish on the east coast of Fujairah.

“Our primary investigation showed that it is Cochlodinium polykrikoides,” said Mohammed Abdurrahman Hassan, head of the marine environment and wildlife section at Dubai Municipality. “It is in patches, it is dense in some areas and thinner in others.”

Mr Hassan called the algae a natural phenomenon.

“We just keep our fingers crossed that it will go away quickly,” he said. “We recommend that people refrain from water activities in the affected areas. Do not catch fish or eat fish that wash ashore.”

Toxic algae is a threat to people who swim in the infested water or who eat seafood from those areas. Of the 20 species of algae common in the UAE, nine are toxic and represent a health concern.

Swimming in infected waters can cause breathing irritation, a sore throat and itchy red eyes.

Jonathan Pickering, 40, a construction consultant who has lived on the Palm for a year, said he would be staying out of the sea following the warning.

He had visited Fujairah in December and said: “It was pretty bad there. I guess this could be related to what they’re experiencing. When I went you couldn’t go snorkelling. The water was dark and black. It’d be a shame if it got that bad over here.”

Toby Haus, an employee at Dubai Marina Yacht Club, said he had taken a boat ride near the World islands and spotted a lot of algae. “There’s a sizeable load of it near the World. There was a significant change in sea colour. It was more brown than red.” The water in the marina remained crystal clear, however, he added.

The red tide algae is native to the Gulf and is not dangerous to humans. However, it damages the gills of fish and deprives the water of oxygen, with a severe impact on marine life.

No signs of damage to the sea creatures living in the waters off Dubai have been seen so far.

Fishermen spotted discolouration of the water far offshore but any movement of the algae towards the beaches would depend on the direction and speed of currents.

There are concerns that the algae could cause similar devastation to marine life and coral witnessed in Dibba and Fujairah where it first emerged last August.

Scientists had hoped that cooler weather in the autumn and winter would kill off the algae, but the bloom has persisted. By last month it was estimated that Asmak, an aquaculture company, had lost 600 tonnes of fish to the outbreak.

The algae has clogged filters at water desalination plants, too. In November the Sharjah Electricity and Water Authority was forced to suspend operations at its plant in Khor Khan.

Hotels, diving centres and beaches have been hit by the swath of red tide up the east coast, costing thousands of dirhams in lost revenue. Hundreds of tonnes of fish have suffocated because of a lack of oxygen in the affected waters.

Coral reefs, the habitat of reef sharks, sea turtles and tropical fish, have also been devastated by the algae, attacking the tiny organisms the reef survives on.

Fishermen in RAK were asked to stop fishing in the waters invaded by the red tide phenomenon as the affected fish could harm consumers. Inspectors from the municipality’s environment and health department seized large quantities of dead fish suspected to have been killed by the red tide about to be put on sale.

The fishermen reported the scale and density of the tide had never been seen before over such a large area. As fishing stocks dwindled, the cost increased sharply.

Algae, also known as phytoplankton, are microorganisms invisible to the naked eye that are a vital food source for other marine creatures. If the balance of the ocean’s environment is disturbed for natural or man-made reasons, their numbers can multiply so rapidly they change the colour of the water.

The East Coast bloom is dominated by several species. Cochlodinium polykrikoides has affected large areas of coastline, spreading to Ras al Khaimah as well as Oman, Iran and the Strait of Hormuz.

Scientists are surprised at its resilience. Signs of coral bleaching – a phenomenon indicative of severe stress – have been observed by divers on many reefs. Natural factors such as high temperatures, sand storms, currents and large amounts of sunlight create conditions for the growth of algae. So do some human activities, including dredging, pollution from fertiliser and sewage. The Ministry of Environment and Water is creating a monitoring and response network of laboratories and trained scientists in collaboration with the Woods Hole Oceanographic Institution, a leading American ocean research organisation. A proposal for a monitoring and management programme has already been put forward to the ministry and is due to be discussed.