There are growing concerns for four captive dolphins in a pen periodically flooded with levels of bacteria considered unsafe for swimming.

Water Bay at St Thomas in the Virgin Islands initially looks to be a pristine holiday spot, but residents have been sharing “alarming” photographs showing discoloured water flooding into the area where dolphins are kept.

Local photographers have been using drones to methodically capture the dolphins’ living conditions at Coral World resort.

View photos The water at St Thomas surrounding the dolphin pens at Coral World has been declared unfit for human swimming by authorities on several occasions after storms. Source: Herman van der Heide More

‘Nobody swims in St Thomas’

Real estate agent Marie Benard, 52, told Yahoo News Australia that local residents know to avoid the area for much of the year.

“Nobody swims in St Thomas after a storm anywhere, but especially not in Water Bay,” she said.

“That’s untreated sewage from septic tanks, runoff from parking lots, and that goes untreated into the ocean.”

Ms Benard fears not only for the health of the dolphins, but also for the tourists who disembark from cruise ships and swim with them.

Public records from the Department of Planning and Public Resources indicate that during 2018, enterococci bacteria levels meant the water was “not considered to be safe for swimming or fishing” approximately 40 per cent of the time.

Since the dolphins arrived earlier this year, bacteria levels have continued to intermittently spike – with the department’s most recent tests for July 29 to August 2 suggesting unsafe swimming conditions.

View photos Runoff and sargasso weed approach the dolphin pen on July 25, 2019. Source: Herman van der Heide More

‘Swimmers are considered at risk’

Marine mammal scientist Dr Naomi Rose is concerned by the water conditions at the Coral World pens and issued a request to the Chicago Zoological Society that they abandon any plans to send more dolphins there.

In her petition she noted that high levels of enterococci and coliform, which she described as “typical gastrointestinal bacteria”, suggest sewage contamination.

“Water Bay is a polluted body of water where human swimmers are considered at risk quite often,” she told Yahoo News Australia.

“The dolphins... are just as susceptible to the risks of being in contaminated water as other mammals such as humans are.”

Dr Rose argues that the US Animal and Plant Health Inspection Service hasn’t updated its bacteria level guidelines for captive dolphins since 1984.

She said more recent peer-reviewed research argues safe levels for the marine mammals are “basically the same as for human swimming”.

New Zealand based marine biologist Dr Ingrid Visser is worried about runoff in Water Bay affecting dolphin health and said tourists should stop supporting the attraction.

“These dolphins are not only swimming in water too contaminated for human safety, but they have their eyes and mouths submerged in this fetid water,” she said.

“These dolphins are only kept in the pens at Coral World because people are buying tickets, so if you care, never buy a ticket to any place that keeps dolphins or whales in captivity.”

View photos A diagram created by a resident explains water flows that allow runoff to enter the dolphin enclosure. Source: Herman van der Heide More

Tragic tale of the Coral World dolphins

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