‘Shell-Crushing’ Crabs May Invade Warming Antarctic Waters

It is slowly making conditions suitable for an invasion of shell-crushing crabs on the continental shelf off the western Antarctic peninsula.

Professor Richard Aronson of the Florida Institute of Technology said if the king crabs moved in, they could “radically restructure” the ecosystem.

Soft-bodied organisms are sitting on the antarctic continental shelf, untouched by other creatures.

Crabs that haven’t been in Antarctic waters for millions of years could return to wreak havoc because of global warming, researchers say. By doing so, researchers believe that they will have a better understanding about the ecosystem of the Antarctic and how it may end up changing as a result of climate change.

The crabs are known for the breaking open of outer skeletons of sea creatures like urchins, mollusks and starfish, and feed on the types of organism that are soft-bodied, living there and could potentially wreak great havoc on the ecology in the immediate area. Normally, they can be found in deeper waters in the Antarctic region, where warmer temperatures are prevalent.

King crabs can be found on the ocean bottom in deep waters across the globe and are known to also turn up in the shallower waters of regions that are subpolar. They have thrived for millions of years due to the frigid temperatures there, which make it impossible for predators to survive.

While extremely cold temperatures have created a defense barrier for these creatures, the water is now warming up on and by the shelf. It is crucial to understand how crabs population will affect Antarctic ecosystem.

Over the past few years, researchers have observed these crabs in the waters off the western Antarctic peninsula.

For the first time in 30 million years, the fragile and ultimately diverse ecosystem found in Antarctica’s shallow continental ice shelf is now under threat from destructive predators such as the king crab.

Aronson and his colleagues found that king crabs (Paralomis birsteini) are at about 2,750 feet below the surface of the continental slope.

“The only way to test the hypothesis that the crabs are expanding their depth-range is to track their movements through long-term monitoring”, study co-author James McClintock, of the University of Alabama at Birmingham, said in the release.