Amery Ice Shelf
A thriving community of sea life 200km from the open sea and lying under over 700m of ice surprises Antarctic researchers.
Using a hot water ice drill, researchers from the Census of Antarctic Marine Life, a field project of the global Census of Marine Life, opened a window to a unique community of marine life that thrives in complete darkness underneath 700m of ice and over 1200m of frigid sea water. Located more than 200km from the open sea under the Amery Ice Shelf, this community surprised researchers, who did not expect to find the diversity of life that was present. The community is virtually identical to Antarctic continental shelf communities from open sea areas devoid of ice. This may have profound affect on our understanding of under-ice species' colonization mechanisms.
The ecology of this under-ice community continues to intrigue researchers. The food web in this environment is assumed to be supplied by strong currents, which flush plankton under the ice from the open sea supplying food for particle feeders such as sponges and fan worms. Scavenging species such as urchins and sea snails are also abundant. What is not clear is whether the populations of higher organisms present there are replenished from the sea as well or if they are self-sustaining.
This finding also has implications for the study of seabed sediments, which are being studied for indications of ice sheet advance and retreat in this climate-sensitive environment. Formerly, if fossil remains of this type of community were found in the Antarctic seabed, paleontologists would likely have assumed that the community existed there during a time period when the ice shelf was absent. Now, with this current finding, this assumption is no longer valid. In the quest for a better understanding of the dynamics of ice shelf advance and retreat, this finding will likely change the methods that are used to map ice coverage.
- What: Discovery of an isolated community of sea life under the Amery Ice Shelf
- Who: CAML Scientists --> I. Allison, D. Rasch, J. Pedro, S. Donoghue, R. Brand, A. Drinkell, M. Craven
- When: December 2005
- Where: Under the Amery Ice Shelf in Antarctica, below 722m of ice and 1265m of water
- How: A hot water ice drill was used to bore through the ice and a digital video camera was lowered down to the sea floor.
- References: This discovery has not yet been published.