Feature 

Cathie Page surveying infected coral on Yonge reef off Lizard Island

White Syndrome has taken hold of this Tabulate Acropora coral

Further example of 'White Syndrome' taking hold on this Tabulate Acropora coral

Digitate Acropora

Over the past 
four years 
the prevalence of 
White Syndrome 
has increased by 
400 percent. 

Tabulate Acropora coral with
'White Syndrome'

The importance of long-term monitoring of the Great Barrier Reef was highlighted this week, when scientists at the Australian Institute of Marine Science confirmed the prevalence of coral disease on the Reef. 

Scientists within the AIMS long-term monitoring program have placed the disease they are seeing in a broad White Syndrome category. They hope to soon learn exactly what White Syndrome is. 

"It’s more common on table corals. It starts at the base and works its way up. The disease breaks the coral tissue down, eventually killing it, " said Cathie Page a benthic ecologist on the AIMS long-term monitoring team.

Cathie Page has been a key member of the monitoring team for about three years. After clocking up about 150 dives each year spanning 48 reefs, she says she’s seen White Syndrome kill at varying rates.

"It could kill a colony of 2 metres in diameter in two weeks but in some other cases, it takes months to kill a large colony, " she said.

It’s true the disease could well have been present on the reef long before the AIMS long-term monitoring team became aware of it, but the scientists believe it is unlikely White Syndrome escaped them, especially during extensive surveys over the past decade.

"I don’t think it’s ever been as abundant as now because we would have picked it up during our surveys. If it’s rare we’re more likely to overlook it. But when it became more common in the years up to 1999, White Syndrome surveys were instigated."

In combination with White Syndrome, coral bleaching is a compounding concern. With rising water temperatures over the tropical summers, coral bleaching events are more widespread and happening more often, leaving little time for coral to recover. Scientists fear the disease could be spreading more quickly in corals weakened by bleaching.

"Bleached coral is not healthy and potentially more susceptible to diseases. We don’t know what’s causing this disease. It’s microscopic; it could be a range of things," Ms Page said.

Scientists have recorded the disease in northern waters during the winter months, making this a tricky disease to fathom. They’re also yet to pinpoint the agent killing the coral. "The pathology of the disease is yet to be examined. Samples have been sent off for testing," said Cathie Page.

An extensive examination of the diseased coral has to be carried out in a bid to draw up a profile of the potential threat. While there are a number of other potential diseases on the Great Barrier Reef common to other reefs around the world, this one appears to be different.

"It doesn’t fit the description of diseases found anywhere else in the world, so it might be specific to the Pacific."

AIMS scientists are collaborating with marine researchers overseas. A lot of work has been carried out in the Caribbean, but nothing seems to match the description of White Syndrome.

The first record of coral diseases came from reefs off Belize and Florida in 1973. It wasn’t until 1993 that diseases were noticed on the Great Barrier Reef. When the disease worsened in the late 90s the long-term monitoring team swung into action and started documenting its growth in earnest. 

The disease is progressing across this Acropora colony leaving the coral dead on the left moving towards living tissue on the right

Tabulate Acropora