Antarctic Species Hang on for Dear Life as Icebergs Batter Shores
As the planet continues to warm, with no relief in sight, massive losses of sea ice in Antarctica have left icebergs free to roam for most of the year, and these out-of-control ice chunks are bashing into shores and killing Antarctic species, new research has found.
According to the study, published in the journal Current Biology, icebergs on the shallow seabed - once carpeted with a blanket of numerous species in intense competition for limited space - now mostly support merely one species.
David Barnes of the British Antarctic Survey and colleagues studied the region to determine how climate change may be wiping out entire species, in turn threatening local ecosystems.
"The Antarctic Peninsula can be considered an early warning system - like a canary in a coal mine," Barnes explained in a press release. "Physical changes there are amongst 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.
He added, "A lot of the planet depends on the near-shore environment, not least for food; what happens there to make it less stable is important."
In this recent study, Barnes and his team analyzed surveys of marine life along the Antarctic shore. They also went on frequent dives to document species population counts and observe changes in iceberg activity.
Several species were documented in the area in 1997. But in 2013, only the pioneer species, Fenstrulina rugula, a "rather unremarkable suspension feeder," according to Barnes, was using its tentacles to literally hang on for dear life. And while no Antarctic species disappeared entirely, their numbers were so dismal that their presence was considered irrelevant.
The researchers indicate that volatility to prior stable habitat, Discovery News reported, caused by the drifting icebergs bashing into boulders in the shallow seabed, is responsible.
Researchers did not expect such drastic population changes to occur in such a short period of time. Many scientists insist that climate change is a slow-moving, gradual process - but the competition for Antarctic real estate suggests otherwise.
"Warming is likely to increase ice scour mortality and reduce assemblage complexity and could aid establishment of nonindigenous species," the researchers concluded.
"We expect the deeper seabed to become richer in benthic colonization with more ice shelf collapses and fast ice losses, but hard surfaces in the shallows are likely to become deserts dominated by rapidly colonizing pioneers and responsive scavengers - with little role for spatial competition or even predation in shaping the structure of such assemblages."