New Reef found

[Chargerfan]

A new reef has been found in Australia.

From Nature.com:

A new coral reef has been found off the coast of Australia. Its 120 square kilometres sit in murky waters 30 meters below the surface, leaving researchers rethinking their understanding of the world's reefs.

In May, researchers cruised into Queensland's Gulf of Carpentaria to study the transport and dispersal of sediments from coastal rivers. Instead they found themselves charting a previously unknown reef. "We were quite surprised," Peter Harris of Geosciences Australia. "Initially I thought it was an old relic reef."

The find hints that there may be many more reefs lurking in rarely-studied waters. "It shows you how little we know about reefs," says James Darwin Thomas of the National Coral Reef Institute in Fort Lauderdale, Florida.

The Australian crew spent 5 days mapping the sea floor with echo beams. As each day's work added to the image, it became clear that they were cruising atop a reef, recalls Harris. So they lowered a video camera. "We were surprised to see corals growing there in such abundance," he says. They carefully collected samples to study upon their return to the lab.

The Gulf of Carpentaria is a shallow sea between Queensland's York Peninsula and Cape Arnhem in the Northern Territory. It is cloudy and warm - an unlikely spot to for a reef to thrive, as sediment can smother coral. "This is not the Great Barrier Reef. It is croc city, it's got rivers, it's dirty," says Thomas.

The reef's depth is also unusual. Corals typically grow up to the sea surface, although there are several deep reefs in the Florida Keys and the Caribbean. "There is a lot out there that we haven't discovered, and that we could impact," Harris warns. Cable laying, drilling and fishing might be affecting the underwater ecosystem more than previously thought.

Deep reefs may be an important source of biodiversity, says ecologist Paul Marshall of the Great Barrier Reef Marine Sanctuary in Townsville, Australia. "I suspect that there are corals that are resistant to low light situations; the population could be unique". Such resilient coral species might help revive reefs damaged by disease or trawling.

The Geosciences Australia team plans to return next year. Local prawn fishermen avoid the area because it is unsafe to trawl there, says Harris: "There could be other reefs".

http://www.nature.com/nsu/030616/030616-2.html