Skip to main navigationSkip to main content
The University of Southampton
Ocean and Earth Science, National Oceanography Centre Southampton

A mass invasion of king crabs threatens native Antarctic species

Published: 17 December 2012

Pioneering research by University of Southampton marine ecologist Dr Sven Thatje has been highlighted in the prestigious online magazine Nature. He believes climate change is prompting millions of deep-sea king crabs to move into shallow Antarctic waters and this mass invasion could wipe out endemic species that evolved in absence of major seafloor predators over millions of years.

In 2007, Sven came up with the first evidence that the crabs were moving into Antarctic waters as sea temperatures rose. He had launched a remotely operated vehicle (ROV) to the outer slope of the Antarctic Peninsula to map glacial grooves on the sea floor. However, its cameras also caught sight of 13 king crabs (Paralomis birsteini) between depths of 1,300 and 1,100 metres.

Sampling of king crab Paralomis birsteini  using ROV Isis in waters off the Western Antarctic Peninsula (JC 166, January 2007)
King Crab (Paralomis birsteini)

The marine ecologist had previously studied the cold tolerance of these crabs and concluded that they could probably survive farther north at 2,000-4,000 metres, where the water is a degree or two warmer but was intrigued to discover them on the continental slope only 500 metres below the shelf itself. "These crabs were thriving at 1°C. They were basically at the physiological limit that I had anticipated," he says.

Fellow researcher Professor Craig Smith from the University of Hawaii at Manoa now thinks 1.5million crabs may now live in the sea floor valley of Palmer Deep, after an expedition to the area.

In December 2010, Sven, working with marine biologists Professor Richard Aronson, from the Florida Institute of Technology in Melbourne and Dr James McClintock, from the University of Alabama at Birmingham, returned to Antarctica. They towed a submersible up and down the continental slope near the mouth of Marguerite Trough. The ROV traced 100 kilometres of sea floor, capturing 150,000 photographs that revealed hundreds of the crabs between 2,300 and 830 metres down.

Research in this area continues to attract scientists from around the world, concerned at the implications on the marine environment of the arrival of king crabs.


Related Staff Member

Privacy Settings