SIMS

An unusual abundance of jelly-like creatures has been discovered in inshore waters along the NSW coast from Sydney to Newcastle. The surprise find was made by a team of scientists from the Sydney Institute of Marine Science and colleagues who have just completed a marine survey of the region.

Coastal residents have also encountered vast numbers of these small jelly balls, washed ashore on local beaches over the past few days.

The recent voyage aboard the Marine National Facility Research Vessel Southern Surveyor targeted these gelatinous animals, called salps. While similar in appearance to the more familiar jellyfish, salps have no stingers and pose no safety concerns to swimmers.

Salps are clear, barrel-shaped animals and can range from one to ten centimetres in length. Salps are typically found near the surface of the ocean and as a result they may be washed up onto the beach.



The voyage's Chief Scientist, Professor Iain Suthers says: "We have observed salps in the coastal ocean in numbers never before recorded in Australian waters. In fact, salp numbers are ten times greater than those seen 70 years ago."

Salp abundance typically increases during the spring, but the actual numbers in recent years have never before been monitored.

"The appearance of these animals is seasonal, but this spring their abundance seems to be enhanced by a strong East Australian Current, which brings more nutrients to the surface waters for the algae that the salps prefer to eat," says Professor Suthers. "This stimulates their remarkable growth rates. Local wind and currents then brings them ashore."

Sydney residents have also seen the remains of such blooms as masses of blue-tinged, clear jelly at the high tide mark in recent weeks.

Similar trends of increasing salp abundance have been observed in other waters around the world and are consistent with predicted outcomes of the warming oceans.



One of the research scientists onboard, Dr Anthony J. Richardson, CSIRO Marine and Atmospheric Research and the University of Queensland, says "Salps could be very important to reducing the impacts of climate change.

"Salps feed on small plants in the water known as phytoplankton that take up carbon dioxide during photosynthesis. As part of normal salp growth, they produce heavy, carbon-rich faeces that can sink rapidly to the seafloor, removing carbon from the oceans."

Several research groups globally are exploring the potential role of salps and other marine organisms in carbon sequestration. The Australian research highlights the challenge ahead to understand the impacts of climate change and develop ways to best adapt to future changes in the marine environment.

Scientists have also gone to extraordinary lengths to replicate the surveys conducted in the late 1920s, enabling them to make direct comparisons of salp abundance. The research conducted on RV Southern Surveyor used nets rebuilt to original specifications and followed the collection methods from the previous survey by the MV Warreen 70 years ago.



Further Information:

Visit the Feature Research Voyage Web Page

Prof. lain Suthers, Sydney Institute of Marine Science and University of NSW
Dr Anthony Richardson, CSIRO and University of Queensland
Dr Mark Baird, University of NSW
Dr Jason Everett, University of NSW