King Crab Invasion Likely If Antarctic Waters Get Warmer
If ocean temperatures continue to rise, Antarctica’s unique continental shelf ecosystem could be invaded by predatory crabs, according to researchers at the University of Southampton.
Sven Thatje, an evolutionary ecologist, has been studying the way that water temperature influences the distributions of King crab species in the Southern Ocean.
To confirm his hypothesis that King Crab range was limited by a “thermal barrier” of ocean temperatures, Thatje’s team studied the distribution of 17 species of king crab living at depths between around 500 and 1600 meters in the Southern Ocean.
“The researchers collated data from published records, museum collections, commercial fishing records, and reports from scientific research cruises and then compared those records to water temperatures measured at a range of relevant depths and geographical latitudes” (Futurity).
According to the study’s results, temperatures in and around the West Antarctic Peninsula are rising. These waters are usually too cold for King Crab larvae to survive, but thanks to climate change, the area might soon be more accommodating.
“Rapidly increasing water temperatures observed along the West Antarctic Peninsula could allow king crabs to spread from the slope of the peninsula to the continental shelf itself,” graduate student Sally Hall, who conducted research with Thatje, explained to Futurity.
“This could have considerable ecological consequences. King crabs are voracious predators that crush and then feed on their prey, but they and potentially competing predators such as sharks and rays, and other predatory crustaceans are largely absent on the high-Antarctic continental shelves,” Hall continued.
This study, for the first time, provides a scientists with a baseline indication of the limits of the lithodid distribution around Antarctica, which will be instrumental in any future work on range extensions of King Crab populations.
Antarctica has long been of interest to climate scientists, which has been slowly melting for several decades.
Image Credit: Flickr - p200eric