Where once such boulders were encrusted with a rich assemblage of species, most now support a single species, the study found.
Last year, a survey dive carried out near Rothera Research Station on the Antarctic Peninsula by a team led by David Barnes of the British Antarctic Survey found large areas where no live animals could be found, the first time that this had ever been reported, despite frequent diving in the area.
In the present study, the researchers found that although no species that were present in 1997 had gone locally extinct, many were now so rare as to play little role in the community.
In many areas, only one species, Fenstrulina rugula – a suspension feeder that belongs to a group that’s often referred to as moss animals – was present, making it one of the simplest seabed systems to be found anywhere.
‘The Antarctic Peninsula can be considered an early-warning system,’ Barnes said. ‘Physical changes there are among the most extreme and the biology considered quite sensitive, so it was always likely to be a good place to observe impacts of climate change – but impacts elsewhere are likely to be not too far behind.’
This story was published in the August 2014 edition of Geographical Magazine