Dolphin deaths 'were not caused by humans'

Bacterial infection and old age the probable causes of death.

DUBAI // The Emirates Marine Environmental Group is looking into the mysterious deaths of three dolphins that washed up on Dubai beaches last month.
The bodies were all found within a week, said Laurence Vanneyre, the senior marine project manager at Emeg, a non-profit, non-governmental organisation.
Emeg has not determined what killed the dolphins, but has cited bacterial infection as a possible cause, Ms Vanneyre said yesterday.
The first dolphin, a young common bottlenose dolphin that was 1.91 metres in length,  was discovered by security personnel at
Jebel Ali Port on March 15. The animal is one of the UAE's most common dolphin species.
The second dolphin was discovered on March 20 at a beach in Ghantoot by an Emeg patrol. The 1.9 metre-long female was identified as a spinner dolphin, which derives its name from the characteristic leaps and spins it can perform.
Two days later, a large Indo-Pacific bottlenose dolphin was discovered on a beach close to a hotel at the Palm Jumeirah.
Ms Vanneyre said Emeg has been keeping a database of dead marine animals discovered in Dubai and Abu Dhabi since 2008. On average, between two and five dolphin deaths are recorded each year.
"It is not unusual to find a dead dolphin, but three in one week is quite rare," she said.
However, the number is not large enough to qualify the cause of death as mass stranding.
Many dolphin deaths can be attributed to human interference such as oil and gas exploration, and sonar.
However, Ms Vanneyre said the three recent deaths were not caused by humans.
"We could not find any mark, showing a strike by boat, propeller or entanglement in nets," she said. "For most of the dolphins we find dead, it is obvious they were hit by boats, but these - no."
It is thought that the large Indo-Pacific bottlenose dolphin died of old age, while the other two most likely died of bacterial infections.
Ms Vanneyre has appealed to UAE residents to report dead dolphins, dugongs and whales to Emeg.
The group's database, as well as tissue samples they obtain from the dead animals, can prove useful in determining mortality rates and learning more about the genetic make-up of the marine mammal populations in the country, she said.
To contact Emeg, visit emeg.ae, email [e-mail] or call + 971 4 363 0581.

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