Physical Controls on Deep Water Coral Communities on the George V Land Slope, East Antarctica

• Published in: Antarctic Science
• Other Authors: APOST (custodian), Beaman, R.J. (author), Commonwealth of Australia (Geoscience Australia) (owner), Commonwealth of Australia (Geoscience Australia) (pointOfContact), De Santis, L. (author), EGD (hasAssociationWith), Manager Client Services (distributor), Manager Client Services (custodian), O'Brien, P.E. (author), Post, A.L. (author), Riddle, M.J. (author)
• Format: Text
• Language: unknown
• Published: Australian Ocean Data Network
• Subjects: geoscientificInformation; External Publication; Abstract; Antarctic data; abiotic surrogates; habitat; marine biodiversity; marine; AQ; EARTH SCIENCES; Published_External; Antarctic; The Antarctic; East Antarctica; George V Land; Antarc*; Antarctica; Iceberg*
• Online Access: https://researchdata.edu.au/physical-controls-deep-east-antarctica/682339; https://pid.geoscience.gov.au/dataset/ga/69723; https://doi.org/10.1017/S0954102010000180

Maintenance and Update Frequency: unknown Statement: Unknown Dense coral-sponge communities on the upper continental slope at 570 - 950 m off George V Land have been identified as a Vulnerable Marine Ecosystem in the Antarctic. The challenge is now to understand their likely distribution. Based on results from the Collaborative East Antarctic Marine Census survey of 2007/2008, we propose some hypotheses to explain their distribution. Icebergs scour to 500 m in this region and the lack of such disturbance is probably a factor allowing growth of rich benthic ecosystems. In addition, the richest communities are found in the heads of canyons. Two possible oceanographic mechanisms may link abundant filter feeder communities and canyon heads. The canyons in which they occur receive descending plumes of Antarctic Bottom Water formed on the George V shelf and these water masses could entrain abundant food for the benthos. Another possibility is that the canyons harbouring rich benthos are those that cut the shelf break. Such canyons are known sites of high productivity in other areas because of a number of oceanographic factors, including strong current flow and increased mixing with shelf waters, and the abrupt, complex topography. These hypotheses provide a framework for the identification of areas where there is a higher likelihood of encountering these Vulnerable Marine Ecosystems.