Iceberg - B15A

Not only can such enormous ice-bergs cause problems for shipping, they can create major problems for wildlife. In 2004 this iceberg, B15A of 3,000 square km (1,200 square miles which contains about as much freshwater as would flow through the Nile river system in 80 years) blocked off access for colonies of Adelie penguins at Cape Crozier and Cape Royds so reducing penguin breeding success to about 10% or less of the normal amount. Eventually the berg moved away so ending fears that it may have become grounded for years so hugely disrupting shipping and possibly threatening the continued viability of some penguin colonies in the area.

Picture courtesy of Mike Usher - Mike went on a Ross Sea expedition on board the Kapitan Khlebnikov in 2005.
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